diff --git a/.clang-tidy b/.clang-tidy
index 5878028f48..4e128a1945 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -5,24 +5,30 @@ Checks: >-
   -altera-*,
   -android-*,
   -boost-*,
+  -bugprone-derived-method-shadowing-base-method,
   -bugprone-easily-swappable-parameters,
   -bugprone-implicit-widening-of-multiplication-result,
+  -bugprone-invalid-enum-default-initialization,
   -bugprone-multi-level-implicit-pointer-conversion,
   -bugprone-narrowing-conversions,
+  -bugprone-tagged-union-member-count,
   -bugprone-signed-char-misuse,
   -bugprone-switch-missing-default-case,
   -cert-dcl50-cpp,
   -cert-err33-c,
   -cert-err58-cpp,
+  -cert-int09-c,
   -cert-oop57-cpp,
   -cert-str34-c,
   -clang-analyzer-optin.core.EnumCastOutOfRange,
   -clang-analyzer-optin.cplusplus.UninitializedObject,
   -clang-analyzer-osx.*,
+  -clang-analyzer-security.ArrayBound,
   -clang-diagnostic-delete-abstract-non-virtual-dtor,
   -clang-diagnostic-delete-non-abstract-non-virtual-dtor,
   -clang-diagnostic-deprecated-declarations,
   -clang-diagnostic-ignored-optimization-argument,
+  -clang-diagnostic-missing-designated-field-initializers,
   -clang-diagnostic-missing-field-initializers,
   -clang-diagnostic-shadow-field,
   -clang-diagnostic-unused-const-variable,
@@ -42,6 +48,7 @@ Checks: >-
   -cppcoreguidelines-owning-memory,
   -cppcoreguidelines-prefer-member-initializer,
   -cppcoreguidelines-pro-bounds-array-to-pointer-decay,
+  -cppcoreguidelines-pro-bounds-avoid-unchecked-container-access,
   -cppcoreguidelines-pro-bounds-constant-array-index,
   -cppcoreguidelines-pro-bounds-pointer-arithmetic,
   -cppcoreguidelines-pro-type-const-cast,
@@ -54,12 +61,13 @@ Checks: >-
   -cppcoreguidelines-rvalue-reference-param-not-moved,
   -cppcoreguidelines-special-member-functions,
   -cppcoreguidelines-use-default-member-init,
+  -cppcoreguidelines-use-enum-class,
   -cppcoreguidelines-virtual-class-destructor,
+  -fuchsia-default-arguments-calls,
+  -fuchsia-default-arguments-declarations,
   -fuchsia-multiple-inheritance,
   -fuchsia-overloaded-operator,
   -fuchsia-statically-constructed-objects,
-  -fuchsia-default-arguments-declarations,
-  -fuchsia-default-arguments-calls,
   -google-build-using-namespace,
   -google-explicit-constructor,
   -google-readability-braces-around-statements,
@@ -71,16 +79,23 @@ Checks: >-
   -llvm-else-after-return,
   -llvm-header-guard,
   -llvm-include-order,
+  -llvm-prefer-static-over-anonymous-namespace,
   -llvm-qualified-auto,
+  -llvm-use-ranges,
   -llvmlibc-*,
   -misc-const-correctness,
   -misc-include-cleaner,
+  -misc-multiple-inheritance,
   -misc-no-recursion,
   -misc-non-private-member-variables-in-classes,
+  -misc-override-with-different-visibility,
   -misc-unused-parameters,
   -misc-use-anonymous-namespace,
+  -misc-use-internal-linkage,
   -modernize-avoid-bind,
+  -modernize-avoid-variadic-functions,
   -modernize-avoid-c-arrays,
+  -modernize-avoid-c-style-cast,
   -modernize-concat-nested-namespaces,
   -modernize-macro-to-enum,
   -modernize-return-braced-init-list,
@@ -88,32 +103,42 @@ Checks: >-
   -modernize-use-auto,
   -modernize-use-constraints,
   -modernize-use-default-member-init,
+  -modernize-use-designated-initializers,
   -modernize-use-equals-default,
+  -modernize-use-integer-sign-comparison,
   -modernize-use-nodiscard,
   -modernize-use-nullptr,
-  -modernize-use-nodiscard,
-  -modernize-use-nullptr,
+  -modernize-use-ranges,
   -modernize-use-trailing-return-type,
   -mpi-*,
   -objc-*,
   -performance-enum-size,
+  -portability-avoid-pragma-once,
+  -portability-template-virtual-member-function,
+  -readability-ambiguous-smartptr-reset-call,
   -readability-avoid-nested-conditional-operator,
   -readability-container-contains,
   -readability-container-data-pointer,
   -readability-convert-member-functions-to-static,
   -readability-else-after-return,
+  -readability-enum-initial-value,
   -readability-function-cognitive-complexity,
   -readability-implicit-bool-conversion,
   -readability-isolate-declaration,
   -readability-magic-numbers,
   -readability-make-member-function-const,
+  -readability-math-missing-parentheses,
   -readability-named-parameter,
   -readability-redundant-casting,
   -readability-redundant-inline-specifier,
   -readability-redundant-member-init,
+  -readability-redundant-parentheses,
   -readability-redundant-string-init,
+  -readability-redundant-typename,
   -readability-uppercase-literal-suffix,
   -readability-use-anyofallof,
+  -readability-use-std-min-max,
+  -readability-use-concise-preprocessor-directives,
 WarningsAsErrors: '*'
 FormatStyle:     google
 CheckOptions:
diff --git a/.clang-tidy.hash b/.clang-tidy.hash
index 41e1b7bd2f..582e0c1eaa 100644
--- a/.clang-tidy.hash
+++ b/.clang-tidy.hash
@@ -1 +1 @@
-1b1ce6324c50c4595703c7df0a8a479b4fe84b71ff1a8793cce1a16f17a33324
+0c7f309d70eca8e3efd510092ddb23c530f3934c49371717efa124b788d761f8
diff --git a/.github/workflows/auto-label-pr.yml b/.github/workflows/auto-label-pr.yml
index 0e5ceb9346..ea22f75ef0 100644
--- a/.github/workflows/auto-label-pr.yml
+++ b/.github/workflows/auto-label-pr.yml
@@ -27,9 +27,9 @@ jobs:
 
       - name: Generate a token
         id: generate-token
-        uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v2
+        uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v3.1.1
         with:
-          app-id: ${{ secrets.ESPHOME_GITHUB_APP_ID }}
+          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
           private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
 
       - name: Auto Label PR
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 20c349ac00..87058e4fa5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -39,7 +39,7 @@ jobs:
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Generate cache-key
         id: cache-key
-        run: echo key="${{ hashFiles('requirements.txt', 'requirements_test.txt', '.pre-commit-config.yaml') }}" >> $GITHUB_OUTPUT
+        run: echo key="${{ hashFiles('requirements.txt', 'requirements_dev.txt', 'requirements_test.txt', '.pre-commit-config.yaml') }}" >> $GITHUB_OUTPUT
       - name: Set up Python ${{ env.DEFAULT_PYTHON }}
         id: python
         uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
@@ -58,7 +58,7 @@ jobs:
           python -m venv venv
           . venv/bin/activate
           python --version
-          pip install -r requirements.txt -r requirements_test.txt pre-commit
+          pip install -r requirements.txt -r requirements_dev.txt -r requirements_test.txt pre-commit
           pip install -e .
 
   pylint:
@@ -108,6 +108,81 @@ jobs:
           script/generate-esp32-boards.py --check
           script/generate-rp2040-boards.py --check
 
+  import-time:
+    name: Check import esphome.__main__ time
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: needs.determine-jobs.outputs.import-time == 'true'
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Check import time against budget and write waterfall HAR
+        run: |
+          . venv/bin/activate
+          script/check_import_time.py --check --har importtime.har
+      - name: Upload waterfall HAR
+        if: always()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: import-time-waterfall
+          path: importtime.har
+          if-no-files-found: ignore
+          retention-days: 14
+
+  device-builder:
+    name: Test downstream esphome/device-builder
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: needs.determine-jobs.outputs.device-builder == 'true'
+    steps:
+      - name: Check out esphome (this PR)
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          path: esphome
+      - name: Check out esphome/device-builder
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          repository: esphome/device-builder
+          ref: main
+          path: device-builder
+      - name: Set up Python
+        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
+        with:
+          python-version: "3.13"
+      - name: Set up uv
+        # Mirrors the install shape device-builder's own CI uses
+        # (esphome/device-builder#192): uv replaces pip for the
+        # install step (order-of-magnitude faster on cold boots,
+        # with its own wheel cache). actions/setup-python still
+        # provides the interpreter.
+        uses: astral-sh/setup-uv@08807647e7069bb48b6ef5acd8ec9567f424441b # v8.1.0
+        with:
+          enable-cache: true
+      - name: Install device-builder + esphome from PR
+        # Install device-builder with its esphome + test extras
+        # first so its pinned versions of pytest/etc. land, then
+        # overlay the PR's esphome so the downstream tests run
+        # against this PR's Python code. ``--system`` installs into
+        # the runner's Python instead of a venv.
+        run: |
+          uv pip install --system -e './device-builder[esphome,test]'
+          uv pip install --system -e ./esphome
+      - name: Run device-builder pytest
+        # ``-n auto`` runs under pytest-xdist (matches device-builder's
+        # own CI). No ``--cov`` here -- this is purely a downstream
+        # smoke check against this PR's esphome code.
+        working-directory: device-builder
+        run: pytest -q -n auto --maxfail=5 --durations=10 --no-cov --ignore=tests/benchmarks
+
   pytest:
     name: Run pytest
     strategy:
@@ -171,11 +246,12 @@ jobs:
       - common
     outputs:
       integration-tests: ${{ steps.determine.outputs.integration-tests }}
-      integration-tests-run-all: ${{ steps.determine.outputs.integration-tests-run-all }}
-      integration-test-files: ${{ steps.determine.outputs.integration-test-files }}
+      integration-test-buckets: ${{ steps.determine.outputs.integration-test-buckets }}
       clang-tidy: ${{ steps.determine.outputs.clang-tidy }}
       clang-tidy-mode: ${{ steps.determine.outputs.clang-tidy-mode }}
       python-linters: ${{ steps.determine.outputs.python-linters }}
+      import-time: ${{ steps.determine.outputs.import-time }}
+      device-builder: ${{ steps.determine.outputs.device-builder }}
       changed-components: ${{ steps.determine.outputs.changed-components }}
       changed-components-with-tests: ${{ steps.determine.outputs.changed-components-with-tests }}
       directly-changed-components-with-tests: ${{ steps.determine.outputs.directly-changed-components-with-tests }}
@@ -214,11 +290,12 @@ jobs:
 
           # Extract individual fields
           echo "integration-tests=$(echo "$output" | jq -r '.integration_tests')" >> $GITHUB_OUTPUT
-          echo "integration-tests-run-all=$(echo "$output" | jq -r '.integration_tests_run_all')" >> $GITHUB_OUTPUT
-          echo "integration-test-files=$(echo "$output" | jq -c '.integration_test_files')" >> $GITHUB_OUTPUT
+          echo "integration-test-buckets=$(echo "$output" | jq -c '.integration_test_buckets')" >> $GITHUB_OUTPUT
           echo "clang-tidy=$(echo "$output" | jq -r '.clang_tidy')" >> $GITHUB_OUTPUT
           echo "clang-tidy-mode=$(echo "$output" | jq -r '.clang_tidy_mode')" >> $GITHUB_OUTPUT
           echo "python-linters=$(echo "$output" | jq -r '.python_linters')" >> $GITHUB_OUTPUT
+          echo "import-time=$(echo "$output" | jq -r '.import_time')" >> $GITHUB_OUTPUT
+          echo "device-builder=$(echo "$output" | jq -r '.device_builder')" >> $GITHUB_OUTPUT
           echo "changed-components=$(echo "$output" | jq -c '.changed_components')" >> $GITHUB_OUTPUT
           echo "changed-components-with-tests=$(echo "$output" | jq -c '.changed_components_with_tests')" >> $GITHUB_OUTPUT
           echo "directly-changed-components-with-tests=$(echo "$output" | jq -c '.directly_changed_components_with_tests')" >> $GITHUB_OUTPUT
@@ -237,12 +314,16 @@ jobs:
           key: components-graph-${{ hashFiles('esphome/components/**/*.py') }}
 
   integration-tests:
-    name: Run integration tests
+    name: Run integration tests (${{ matrix.bucket.name }})
     runs-on: ubuntu-latest
     needs:
       - common
       - determine-jobs
     if: needs.determine-jobs.outputs.integration-tests == 'true'
+    strategy:
+      fail-fast: false
+      matrix:
+        bucket: ${{ fromJson(needs.determine-jobs.outputs.integration-test-buckets) }}
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
@@ -269,19 +350,14 @@ jobs:
         run: echo "::add-matcher::.github/workflows/matchers/pytest.json"
       - name: Run integration tests
         env:
-          INTEGRATION_TEST_FILES: ${{ needs.determine-jobs.outputs.integration-test-files }}
-          INTEGRATION_TESTS_RUN_ALL: ${{ needs.determine-jobs.outputs.integration-tests-run-all }}
+          # JSON array of test paths; parsed into a bash array below to avoid
+          # shell word-splitting / glob hazards.
+          BUCKET_TESTS: ${{ toJson(matrix.bucket.tests) }}
         run: |
           . venv/bin/activate
-          if [[ "$INTEGRATION_TESTS_RUN_ALL" == "true" ]]; then
-            echo "Running all integration tests"
-            pytest -vv --no-cov --tb=native -n auto tests/integration/
-          else
-            # Parse JSON array into bash array to avoid shell expansion issues
-            mapfile -t test_files < <(echo "$INTEGRATION_TEST_FILES" | jq -r '.[]')
-            echo "Running ${#test_files[@]} specific integration tests"
-            pytest -vv --no-cov --tb=native -n auto "${test_files[@]}"
-          fi
+          mapfile -t test_files < <(echo "$BUCKET_TESTS" | jq -r '.[]')
+          echo "Bucket ${{ matrix.bucket.name }}: running ${#test_files[@]} integration tests"
+          pytest -vv --no-cov --tb=native -n auto "${test_files[@]}"
 
   cpp-unit-tests:
     name: Run C++ unit tests
@@ -339,7 +415,7 @@ jobs:
           echo "binary=$BINARY" >> $GITHUB_OUTPUT
 
       - name: Run CodSpeed benchmarks
-        uses: CodSpeedHQ/action@658a901452bb54c799643e060733b7afe9121b8d # v4.14.0
+        uses: CodSpeedHQ/action@c381be0bfd20e844fb45594f6aa182ffcd94545c # v4.15.0
         with:
           run: ${{ steps.build.outputs.binary }}
           mode: simulation
@@ -1036,6 +1112,7 @@ jobs:
       - clang-tidy-nosplit
       - clang-tidy-split
       - determine-jobs
+      - device-builder
       - test-build-components-split
       - pre-commit-ci-lite
       - memory-impact-target-branch
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 246a865693..5429434a7f 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -58,7 +58,7 @@ jobs:
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@95e58e9a2cdfd71adc6e0353d5c52f41a045d225 # v4.35.2
+        uses: github/codeql-action/init@e46ed2cbd01164d986452f91f178727624ae40d7 # v4.35.3
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
@@ -86,6 +86,6 @@ jobs:
           exit 1
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@95e58e9a2cdfd71adc6e0353d5c52f41a045d225 # v4.35.2
+        uses: github/codeql-action/analyze@e46ed2cbd01164d986452f91f178727624ae40d7 # v4.35.3
         with:
           category: "/language:${{matrix.language}}"
diff --git a/.github/workflows/lock.yml b/.github/workflows/lock.yml
index 20f9a74ea9..8d1dfe857d 100644
--- a/.github/workflows/lock.yml
+++ b/.github/workflows/lock.yml
@@ -8,4 +8,4 @@ on:
 
 jobs:
   lock:
-    uses: esphome/workflows/.github/workflows/lock.yml@3c4e8446aa1029f1c346a482034b3ee1489077ca  # 2026.4.0
+    uses: esphome/workflows/.github/workflows/lock.yml@025a1e6255610c498ed590403b7e510b69e474df  # 2026.4.1
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 35b9e065e1..a16af92b6f 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -223,7 +223,7 @@ jobs:
         id: generate-token
         uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v3.1.1
         with:
-          app-id: ${{ secrets.ESPHOME_GITHUB_APP_ID }}
+          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
           private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
           owner: esphome
           repositories: home-assistant-addon
@@ -258,7 +258,7 @@ jobs:
         id: generate-token
         uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v3.1.1
         with:
-          app-id: ${{ secrets.ESPHOME_GITHUB_APP_ID }}
+          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
           private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
           owner: esphome
           repositories: esphome-schema
@@ -289,7 +289,7 @@ jobs:
         id: generate-token
         uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v3.1.1
         with:
-          app-id: ${{ secrets.ESPHOME_GITHUB_APP_ID }}
+          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
           private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
           owner: esphome
           repositories: version-notifier
diff --git a/.gitignore b/.gitignore
index da568d9b83..4a4a88fd48 100644
--- a/.gitignore
+++ b/.gitignore
@@ -146,5 +146,6 @@ sdkconfig.*
 
 /components
 /managed_components
+/dependencies.lock
 
 api-docs/
diff --git a/CODEOWNERS b/CODEOWNERS
index 7175685a8c..cf0a02a032 100644
--- a/CODEOWNERS
+++ b/CODEOWNERS
@@ -348,6 +348,7 @@ esphome/components/modbus_controller/select/* @martgras @stegm
 esphome/components/modbus_controller/sensor/* @martgras
 esphome/components/modbus_controller/switch/* @martgras
 esphome/components/modbus_controller/text_sensor/* @martgras
+esphome/components/modbus_server/* @exciton
 esphome/components/mopeka_ble/* @Fabian-Schmidt @spbrogan
 esphome/components/mopeka_pro_check/* @spbrogan
 esphome/components/mopeka_std_check/* @Fabian-Schmidt
diff --git a/esphome/__main__.py b/esphome/__main__.py
index 8c80dab90a..9ab2dee189 100644
--- a/esphome/__main__.py
+++ b/esphome/__main__.py
@@ -21,7 +21,7 @@ import argcomplete
 # Note: Do not import modules from esphome.components here, as this would
 # cause them to be loaded before external components are processed, resulting
 # in the built-in version being used instead of the external component one.
-from esphome import const, writer, yaml_util
+from esphome import const
 import esphome.codegen as cg
 from esphome.config import iter_component_configs, read_config, strip_default_ids
 from esphome.const import (
@@ -72,7 +72,12 @@ from esphome.util import (
     run_external_process,
     safe_print,
 )
-from esphome.zeroconf import discover_mdns_devices
+
+# Keep expensive imports (zeroconf, writer, yaml_util, etc.) out of this
+# module's top level. Every `esphome` invocation — including fast paths
+# like `esphome version` — pays the cost of what's imported here before
+# any command runs. Import inside the function that needs it instead.
+# `script/check_import_time.py` enforces a budget in CI.
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -241,6 +246,8 @@ def _discover_mac_suffix_devices() -> list[str] | None:
     """
     if not (has_name_add_mac_suffix() and has_mdns() and has_non_ip_address()):
         return None
+    from esphome.zeroconf import discover_mdns_devices
+
     _LOGGER.info("Discovering devices...")
     if not (discovered := discover_mdns_devices(CORE.name)):
         _LOGGER.warning(
@@ -660,7 +667,7 @@ def run_miniterm(config: ConfigType, port: str, args) -> int:
     return 0
 
 
-def wrap_to_code(name, comp):
+def _wrap_to_code(name, comp, yaml_util):
     coro = coroutine(comp.to_code)
 
     @functools.wraps(comp.to_code)
@@ -680,6 +687,8 @@ def wrap_to_code(name, comp):
 
 
 def write_cpp(config: ConfigType, native_idf: bool = False) -> int:
+    from esphome import writer
+
     if not get_bool_env(ENV_NOGITIGNORE):
         writer.write_gitignore()
 
@@ -691,17 +700,21 @@ def write_cpp(config: ConfigType, native_idf: bool = False) -> int:
 
 
 def generate_cpp_contents(config: ConfigType) -> None:
+    from esphome import yaml_util
+
     _LOGGER.info("Generating C++ source...")
 
     for name, component, conf in iter_component_configs(CORE.config):
         if component.to_code is not None:
-            coro = wrap_to_code(name, component)
+            coro = _wrap_to_code(name, component, yaml_util)
             CORE.add_job(coro, conf)
 
     CORE.flush_tasks()
 
 
 def write_cpp_file(native_idf: bool = False) -> int:
+    from esphome import writer
+
     code_s = indent(CORE.cpp_main_section)
     writer.write_cpp(code_s)
 
@@ -1078,6 +1091,15 @@ def upload_program(
 
     port_type = get_port_type(host)
 
+    # MQTT and MQTTIP are also OTA paths; MQTTIP gets resolved to a real IP later by
+    # _resolve_network_devices(). Only SERIAL and BOOTSEL are non-OTA upload paths.
+    if port_type in (PortType.SERIAL, PortType.BOOTSEL) and getattr(
+        args, "partition_table", False
+    ):
+        raise EsphomeError(
+            "The option --partition-table can only be used for Over The Air updates."
+        )
+
     if port_type == PortType.BOOTSEL:
         exit_code = upload_using_picotool(config)
         # Return None for device - BOOTSEL can't be used for logging,
@@ -1112,15 +1134,84 @@ def upload_program(
 
     remote_port = int(ota_conf[CONF_PORT])
     password = ota_conf.get(CONF_PASSWORD)
-    if getattr(args, "file", None) is not None:
-        binary = Path(args.file)
-    else:
-        binary = CORE.firmware_bin
 
     # Resolve MQTT magic strings to actual IP addresses
     network_devices = _resolve_network_devices(devices, config, args)
 
-    return espota2.run_ota(network_devices, remote_port, password, binary)
+    binary = CORE.firmware_bin
+    ota_type = espota2.OTA_TYPE_UPDATE_APP
+    if getattr(args, "partition_table", False):
+        # Fail fast if the resolved ESPHome OTA config does not enable allow_partition_access.
+        # The device-side handshake also rejects this with "Device only supports app updates",
+        # but checking here surfaces the misconfiguration before opening a network connection.
+        if not ota_conf.get("allow_partition_access"):
+            raise EsphomeError(
+                "The option --partition-table requires 'allow_partition_access: true' on the "
+                "esphome OTA platform in the device's YAML configuration. Add it, recompile, "
+                "flash a build with the option enabled, and then retry --partition-table."
+            )
+        binary = CORE.partition_table_bin
+        ota_type = espota2.OTA_TYPE_UPDATE_PARTITION_TABLE
+    if getattr(args, "file", None) is not None:
+        binary = Path(args.file)
+
+    if ota_type == espota2.OTA_TYPE_UPDATE_PARTITION_TABLE:
+        _validate_partition_table_binary(binary)
+
+    return espota2.run_ota(network_devices, remote_port, password, binary, ota_type)
+
+
+# Layout of esp_partition_info_t on flash. Each entry is 32 bytes, leading with a
+# 16-bit little-endian magic. ESP-IDF defines ESP_PARTITION_MAGIC = 0x50AA (stored as
+# bytes 0xAA, 0x50) for partition entries and ESP_PARTITION_MAGIC_MD5 = 0xEBEB for the
+# trailing checksum entry. Padding past the last entry is 0xFF. The full table is
+# exactly ESP_PARTITION_TABLE_MAX_LEN bytes.
+_PARTITION_TABLE_MAX_LEN = 0xC00
+_ESP_PARTITION_MAGIC = 0x50AA
+_ESP_PARTITION_MAGIC_MD5 = 0xEBEB
+
+
+def _validate_partition_table_binary(binary: Path) -> None:
+    """Validate that ``binary`` looks like an ESP32 partition table image.
+
+    Catches common mistakes (wrong file, truncated build output, swapped --file path)
+    before opening a network connection so the failure mode is a clear local error
+    instead of a post-handshake device rejection.
+    """
+    try:
+        data = binary.read_bytes()
+    except OSError as err:
+        raise EsphomeError(
+            f"Cannot read partition table file '{binary}': {err}"
+        ) from err
+
+    if len(data) != _PARTITION_TABLE_MAX_LEN:
+        raise EsphomeError(
+            f"Partition table file '{binary}' has wrong size: expected "
+            f"{_PARTITION_TABLE_MAX_LEN} bytes, got {len(data)}. "
+            "Pass the partition table image (e.g. partitions.bin / partition-table.bin), "
+            "not the firmware image."
+        )
+
+    first_magic = data[0] | (data[1] << 8)
+    if first_magic != _ESP_PARTITION_MAGIC:
+        raise EsphomeError(
+            f"Partition table file '{binary}' does not start with the expected "
+            f"partition magic 0x{_ESP_PARTITION_MAGIC:04X} (got 0x{first_magic:04X}). "
+            "This file does not look like an ESP32 partition table."
+        )
+
+    # The MD5 checksum entry is required: without it the device-side
+    # esp_partition_table_verify will accept the table but the bootloader will
+    # refuse to boot from it. Scan the 32-byte entries for the MD5 magic.
+    if not any(
+        (data[off] | (data[off + 1] << 8)) == _ESP_PARTITION_MAGIC_MD5
+        for off in range(0, _PARTITION_TABLE_MAX_LEN, 32)
+    ):
+        raise EsphomeError(
+            f"Partition table file '{binary}' is missing the MD5 checksum entry. "
+            "Regenerate the partition table with gen_esp32part.py or rebuild the project."
+        )
 
 
 def show_logs(config: ConfigType, args: ArgsProtocol, devices: list[str]) -> int | None:
@@ -1180,6 +1271,8 @@ def command_wizard(args: ArgsProtocol) -> int | None:
 
 
 def command_config(args: ArgsProtocol, config: ConfigType) -> int | None:
+    from esphome import yaml_util
+
     if not CORE.verbose:
         config = strip_default_ids(config)
     output = yaml_util.dump(config, args.show_secrets)
@@ -1321,6 +1414,8 @@ def command_clean_mqtt(args: ArgsProtocol, config: ConfigType) -> int | None:
 
 
 def command_clean_all(args: ArgsProtocol) -> int | None:
+    from esphome import writer
+
     try:
         writer.clean_all(args.configuration)
     except OSError as err:
@@ -1336,6 +1431,8 @@ def command_version(args: ArgsProtocol) -> int | None:
 
 
 def command_clean(args: ArgsProtocol, config: ConfigType) -> int | None:
+    from esphome import writer
+
     try:
         writer.clean_build()
     except OSError as err:
@@ -1538,6 +1635,8 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
 
 
 def command_rename(args: ArgsProtocol, config: ConfigType) -> int | None:
+    from esphome import yaml_util
+
     new_name = args.name
     for c in new_name:
         if c not in ALLOWED_NAME_CHARS:
@@ -1782,6 +1881,11 @@ def parse_args(argv):
         "--file",
         help="Manually specify the binary file to upload.",
     )
+    parser_upload.add_argument(
+        "--partition-table",
+        help="Upload as partition table (OTA).",
+        action="store_true",
+    )
 
     parser_logs = subparsers.add_parser(
         "logs",
diff --git a/esphome/analyze_memory/__init__.py b/esphome/analyze_memory/__init__.py
index f56d720ec2..33854ac289 100644
--- a/esphome/analyze_memory/__init__.py
+++ b/esphome/analyze_memory/__init__.py
@@ -793,8 +793,11 @@ class MemoryAnalyzer:
         """Scan ESPHome source object files to map extern "C" symbols to components.
 
         When no linker map file is available, this uses ``nm`` to scan ``.o`` files
-        under ``src/esphome/`` and build a symbol-to-component mapping. This catches
-        ``extern "C"`` functions and other symbols that lack C++ namespace prefixes.
+        under ``src/`` (including ``src/main.cpp.o`` and everything beneath
+        ``src/esphome/``) and build a symbol-to-component mapping. This catches
+        ``extern "C"`` functions, the ESPHome-generated ``setup()``/``loop()``
+        entry points in ``main.cpp``, and other symbols that lack C++ namespace
+        prefixes.
 
         Skips scanning if ``_source_symbol_map`` was already populated by
         ``_parse_map_file()``.
@@ -806,12 +809,12 @@ class MemoryAnalyzer:
         if obj_dir is None:
             return
 
-        # Find ESPHome source object files
-        esphome_src_dir = obj_dir / "src" / "esphome"
-        if not esphome_src_dir.is_dir():
+        # Scan all ESPHome-owned source object files: src/main.cpp.o and src/esphome/...
+        src_dir = obj_dir / "src"
+        if not src_dir.is_dir():
             return
 
-        obj_files = sorted(esphome_src_dir.rglob("*.o"))
+        obj_files = sorted(src_dir.rglob("*.o"))
         if not obj_files:
             return
 
@@ -1064,6 +1067,10 @@ class MemoryAnalyzer:
                 if component_name in self.external_components:
                     return f"{_COMPONENT_PREFIX_EXTERNAL}{component_name}"
 
+        # ESPHome-generated entry point: src/main.cpp.o (contains setup()/loop())
+        if len(parts) >= 2 and parts[-2:] == ("src", "main.cpp.o"):
+            return _COMPONENT_CORE
+
         # ESPHome core: src/esphome/core/... or src/esphome/...
         if "core" in parts and "esphome" in parts:
             return _COMPONENT_CORE
diff --git a/esphome/automation.py b/esphome/automation.py
index 97d9a0a47a..1689d29c42 100644
--- a/esphome/automation.py
+++ b/esphome/automation.py
@@ -127,7 +127,7 @@ def validate_potentially_or_condition(value):
     return validate_condition(value)
 
 
-DelayAction = cg.esphome_ns.class_("DelayAction", Action, cg.Component)
+DelayAction = cg.esphome_ns.class_("DelayAction", Action)
 LambdaAction = cg.esphome_ns.class_("LambdaAction", Action)
 StatelessLambdaAction = cg.esphome_ns.class_("StatelessLambdaAction", Action)
 IfAction = cg.esphome_ns.class_("IfAction", Action)
@@ -396,7 +396,6 @@ async def delay_action_to_code(
     args: TemplateArgsType,
 ) -> MockObj:
     var = cg.new_Pvariable(action_id, template_arg)
-    await cg.register_component(var, {})
     template_ = await cg.templatable(config, args, cg.uint32)
     cg.add(var.set_delay(template_))
     return var
@@ -597,7 +596,7 @@ async def component_resume_action_to_code(
     comp = await cg.get_variable(config[CONF_ID])
     var = cg.new_Pvariable(action_id, template_arg, comp)
     if CONF_UPDATE_INTERVAL in config:
-        template_ = await cg.templatable(config[CONF_UPDATE_INTERVAL], args, int)
+        template_ = await cg.templatable(config[CONF_UPDATE_INTERVAL], args, cg.uint32)
         cg.add(var.set_update_interval(template_))
     return var
 
diff --git a/esphome/components/adalight/adalight_light_effect.cpp b/esphome/components/adalight/adalight_light_effect.cpp
index 4cf639a01f..06d7e0e897 100644
--- a/esphome/components/adalight/adalight_light_effect.cpp
+++ b/esphome/components/adalight/adalight_light_effect.cpp
@@ -129,7 +129,7 @@ AdalightLightEffect::Frame AdalightLightEffect::parse_frame_(light::AddressableL
   uint8_t *led_data = &frame_[6];
 
   for (int led = 0; led < accepted_led_count; led++, led_data += 3) {
-    auto white = std::min(std::min(led_data[0], led_data[1]), led_data[2]);
+    auto white = std::min({led_data[0], led_data[1], led_data[2]});
 
     it[led].set(Color(led_data[0], led_data[1], led_data[2], white));
   }
diff --git a/esphome/components/animation/animation.cpp b/esphome/components/animation/animation.cpp
index c2ae3b2f76..2f59a7fa5a 100644
--- a/esphome/components/animation/animation.cpp
+++ b/esphome/components/animation/animation.cpp
@@ -62,7 +62,12 @@ void Animation::set_frame(int frame) {
 }
 
 void Animation::update_data_start_() {
-  const uint32_t image_size = this->get_width_stride() * this->height_;
+  uint32_t image_size = this->get_width_stride() * this->height_;
+  // RGB565 with an alpha channel stores the alpha plane immediately after the RGB
+  // plane within each frame, so the per-frame stride includes the alpha bytes.
+  if (this->type_ == image::IMAGE_TYPE_RGB565 && this->transparency_ == image::TRANSPARENCY_ALPHA_CHANNEL) {
+    image_size += static_cast<uint32_t>(this->width_) * this->height_;
+  }
   this->data_start_ = this->animation_data_start_ + image_size * this->current_frame_;
 }
 
diff --git a/esphome/components/api/__init__.py b/esphome/components/api/__init__.py
index ad778f20ad..ca74483a2b 100644
--- a/esphome/components/api/__init__.py
+++ b/esphome/components/api/__init__.py
@@ -72,17 +72,35 @@ APIUnregisterServiceCallAction = api_ns.class_(
 
 UserServiceTrigger = api_ns.class_("UserServiceTrigger", automation.Trigger)
 ListEntitiesServicesArgument = api_ns.class_("ListEntitiesServicesArgument")
-SERVICE_ARG_NATIVE_TYPES: dict[str, MockObj] = {
+# Owning element type for each YAML service variable type.  Used to derive both
+# the zero-copy native types and the owning fallback types below.
+_SERVICE_ARG_SCALAR_TYPES: dict[str, MockObj] = {
     "bool": cg.bool_,
     "int": cg.int32,
     "float": cg.float_,
+    "string": cg.std_string,
+}
+SERVICE_ARG_NATIVE_TYPES: dict[str, MockObj] = {
+    # Scalars are passed by value; string uses a non-owning view into rx_buf_.
+    **_SERVICE_ARG_SCALAR_TYPES,
     "string": cg.StringRef,
-    "bool[]": cg.FixedVector.template(cg.bool_).operator("const").operator("ref"),
-    "int[]": cg.FixedVector.template(cg.int32).operator("const").operator("ref"),
-    "float[]": cg.FixedVector.template(cg.float_).operator("const").operator("ref"),
-    "string[]": cg.FixedVector.template(cg.std_string)
-    .operator("const")
-    .operator("ref"),
+    # Arrays are passed as non-owning const references into rx_buf_.
+    **{
+        f"{name}[]": cg.FixedVector.template(t).operator("const").operator("ref")
+        for name, t in _SERVICE_ARG_SCALAR_TYPES.items()
+    },
+}
+# Owning fallback types used when the action chain contains non-synchronous actions
+# (delay, wait_until, script.wait, etc.).  The default non-owning types reference
+# storage in the receive buffer, which is reused once the synchronous portion of
+# the chain returns.  FixedVector is also non-copyable, so the deferred lambda
+# capture in DelayAction::play_complex would fail to compile.
+SERVICE_ARG_FALLBACK_TYPES: dict[str, MockObj] = {
+    "string": cg.std_string,
+    **{
+        f"{name}[]": cg.std_vector.template(t)
+        for name, t in _SERVICE_ARG_SCALAR_TYPES.items()
+    },
 }
 CONF_ENCRYPTION = "encryption"
 CONF_BATCH_DELAY = "batch_delay"
@@ -381,17 +399,20 @@ async def to_code(config: ConfigType) -> None:
                     func_args.append((cg.bool_, "return_response"))
 
             # Check if action chain has non-synchronous actions that would make
-            # non-owning StringRef dangle (rx_buf_ reused after delay)
+            # non-owning args (StringRef, const FixedVector&) dangle once the
+            # rx_buf_ is reused after a delay/wait_until/script.wait/etc.  The
+            # FixedVector references would also fail to compile because they
+            # are non-copyable and DelayAction captures args by value.
             has_non_synchronous = automation.has_non_synchronous_actions(
                 conf.get(CONF_THEN, [])
             )
 
             service_arg_names: list[str] = []
             for name, var_ in conf[CONF_VARIABLES].items():
-                native = SERVICE_ARG_NATIVE_TYPES[var_]
-                # Fall back to std::string for string args if non-synchronous actions exist
-                if has_non_synchronous and native is cg.StringRef:
-                    native = cg.std_string
+                if has_non_synchronous and var_ in SERVICE_ARG_FALLBACK_TYPES:
+                    native = SERVICE_ARG_FALLBACK_TYPES[var_]
+                else:
+                    native = SERVICE_ARG_NATIVE_TYPES[var_]
                 service_template_args.append(native)
                 func_args.append((native, name))
                 service_arg_names.append(name)
diff --git a/esphome/components/api/api.proto b/esphome/components/api/api.proto
index 1c33d92bea..4d72be5407 100644
--- a/esphome/components/api/api.proto
+++ b/esphome/components/api/api.proto
@@ -1419,6 +1419,8 @@ enum LockState {
   LOCK_STATE_JAMMED = 3;
   LOCK_STATE_LOCKING = 4;
   LOCK_STATE_UNLOCKING = 5;
+  LOCK_STATE_OPENING = 6;
+  LOCK_STATE_OPEN = 7;
 }
 enum LockCommand  {
   LOCK_UNLOCK = 0;
@@ -1637,7 +1639,7 @@ message BluetoothLEAdvertisementResponse {
 
 message BluetoothLERawAdvertisement {
   option (inline_encode) = true;
-  uint64 address = 1 [(force) = true];
+  uint64 address = 1 [(force) = true, (mac_address) = true];
   sint32 rssi = 2 [(force) = true];
   uint32 address_type = 3 [(max_value) = 4];
 
@@ -2509,6 +2511,7 @@ message ZWaveProxyFrame {
   option (source) = SOURCE_BOTH;
   option (ifdef) = "USE_ZWAVE_PROXY";
   option (no_delay) = true;
+  option (speed_optimized) = true;
 
   bytes data = 1;
 }
@@ -2569,6 +2572,7 @@ message InfraredRFReceiveEvent {
   option (source) = SOURCE_SERVER;
   option (ifdef) = "USE_IR_RF || USE_RADIO_FREQUENCY";
   option (no_delay) = true;
+  option (speed_optimized) = true;
 
   uint32 device_id = 1 [(field_ifdef) = "USE_DEVICES"];
   fixed32 key = 2 [(force) = true];     // Key identifying the receiver instance
@@ -2625,6 +2629,7 @@ message SerialProxyDataReceived {
   option (source) = SOURCE_SERVER;
   option (ifdef) = "USE_SERIAL_PROXY";
   option (no_delay) = true;
+  option (speed_optimized) = true;
 
   uint32 instance = 1;          // Instance index (0-based)
   bytes data = 2;               // Raw data received from the serial device
diff --git a/esphome/components/api/api_options.proto b/esphome/components/api/api_options.proto
index d5d0b37e8d..ac9c4e59cc 100644
--- a/esphome/components/api/api_options.proto
+++ b/esphome/components/api/api_options.proto
@@ -110,4 +110,10 @@ extend google.protobuf.FieldOptions {
     // length varint calculations and direct byte writes, since the length
     // varint is guaranteed to be 1 byte.
     optional uint32 max_data_length = 50018;
+
+    // mac_address: Field is a 48-bit MAC address stored in a uint64.
+    // Emits encode_varint_raw_48bit which has a 7-byte fast path that avoids
+    // the per-byte loop when the upper bits are non-zero (the common case
+    // for real MAC addresses, since OUIs occupy the top 24 bits).
+    optional bool mac_address = 50019 [default=false];
 }
diff --git a/esphome/components/api/api_pb2.cpp b/esphome/components/api/api_pb2.cpp
index f6ceee2296..68be7550ee 100644
--- a/esphome/components/api/api_pb2.cpp
+++ b/esphome/components/api/api_pb2.cpp
@@ -2352,7 +2352,7 @@ BluetoothLERawAdvertisementsResponse::encode(ProtoWriteBuffer &buffer PROTO_ENCO
     uint8_t *len_pos = pos;
     ProtoEncode::reserve_byte(pos PROTO_ENCODE_DEBUG_ARG);
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 8);
-    ProtoEncode::encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, sub_msg.address);
+    ProtoEncode::encode_varint_raw_48bit(pos PROTO_ENCODE_DEBUG_ARG, sub_msg.address);
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 16);
     ProtoEncode::encode_varint_raw_short(pos PROTO_ENCODE_DEBUG_ARG, encode_zigzag32(sub_msg.rssi));
     if (sub_msg.address_type) {
@@ -2373,7 +2373,7 @@ BluetoothLERawAdvertisementsResponse::calculate_size() const {
   for (uint16_t i = 0; i < this->advertisements_len; i++) {
     auto &sub_msg = this->advertisements[i];
     size += 2;
-    size += ProtoSize::calc_uint64_force(1, sub_msg.address);
+    size += ProtoSize::calc_uint64_48bit_force(1, sub_msg.address);
     size += ProtoSize::calc_sint32_force(1, sub_msg.rssi);
     size += sub_msg.address_type ? 2 : 0;
     size += 2 + sub_msg.data_len;
@@ -3784,12 +3784,16 @@ bool ZWaveProxyFrame::decode_length(uint32_t field_id, ProtoLengthDelimited valu
   }
   return true;
 }
-uint8_t *ZWaveProxyFrame::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint8_t *
+ZWaveProxyFrame::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
   uint8_t *__restrict__ pos = buffer.get_pos();
   ProtoEncode::encode_bytes(pos PROTO_ENCODE_DEBUG_ARG, 1, this->data, this->data_len);
   return pos;
 }
-uint32_t ZWaveProxyFrame::calculate_size() const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint32_t
+ZWaveProxyFrame::calculate_size() const {
   uint32_t size = 0;
   size += ProtoSize::calc_length(1, this->data_len);
   return size;
@@ -3910,7 +3914,9 @@ bool InfraredRFTransmitRawTimingsRequest::decode_32bit(uint32_t field_id, Proto3
   }
   return true;
 }
-uint8_t *InfraredRFReceiveEvent::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint8_t *
+InfraredRFReceiveEvent::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
   uint8_t *__restrict__ pos = buffer.get_pos();
 #ifdef USE_DEVICES
   ProtoEncode::encode_uint32(pos PROTO_ENCODE_DEBUG_ARG, 1, this->device_id);
@@ -3921,7 +3927,9 @@ uint8_t *InfraredRFReceiveEvent::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DE
   }
   return pos;
 }
-uint32_t InfraredRFReceiveEvent::calculate_size() const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint32_t
+InfraredRFReceiveEvent::calculate_size() const {
   uint32_t size = 0;
 #ifdef USE_DEVICES
   size += ProtoSize::calc_uint32(1, this->device_id);
@@ -4001,13 +4009,17 @@ bool SerialProxyConfigureRequest::decode_varint(uint32_t field_id, proto_varint_
   }
   return true;
 }
-uint8_t *SerialProxyDataReceived::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint8_t *
+SerialProxyDataReceived::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {
   uint8_t *__restrict__ pos = buffer.get_pos();
   ProtoEncode::encode_uint32(pos PROTO_ENCODE_DEBUG_ARG, 1, this->instance);
   ProtoEncode::encode_bytes(pos PROTO_ENCODE_DEBUG_ARG, 2, this->data_ptr_, this->data_len_);
   return pos;
 }
-uint32_t SerialProxyDataReceived::calculate_size() const {
+__attribute__((optimize("O2")))  // NOLINT(clang-diagnostic-unknown-attributes)
+uint32_t
+SerialProxyDataReceived::calculate_size() const {
   uint32_t size = 0;
   size += ProtoSize::calc_uint32(1, this->instance);
   size += ProtoSize::calc_length(1, this->data_len_);
diff --git a/esphome/components/api/api_pb2.h b/esphome/components/api/api_pb2.h
index a8e01c017f..7b82f1884d 100644
--- a/esphome/components/api/api_pb2.h
+++ b/esphome/components/api/api_pb2.h
@@ -181,6 +181,8 @@ enum LockState : uint32_t {
   LOCK_STATE_JAMMED = 3,
   LOCK_STATE_LOCKING = 4,
   LOCK_STATE_UNLOCKING = 5,
+  LOCK_STATE_OPENING = 6,
+  LOCK_STATE_OPEN = 7,
 };
 enum LockCommand : uint32_t {
   LOCK_UNLOCK = 0,
diff --git a/esphome/components/api/api_pb2_dump.cpp b/esphome/components/api/api_pb2_dump.cpp
index 541f5d4d11..5258b355ce 100644
--- a/esphome/components/api/api_pb2_dump.cpp
+++ b/esphome/components/api/api_pb2_dump.cpp
@@ -487,6 +487,10 @@ template<> const char *proto_enum_to_string<enums::LockState>(enums::LockState v
       return ESPHOME_PSTR("LOCK_STATE_LOCKING");
     case enums::LOCK_STATE_UNLOCKING:
       return ESPHOME_PSTR("LOCK_STATE_UNLOCKING");
+    case enums::LOCK_STATE_OPENING:
+      return ESPHOME_PSTR("LOCK_STATE_OPENING");
+    case enums::LOCK_STATE_OPEN:
+      return ESPHOME_PSTR("LOCK_STATE_OPEN");
     default:
       return ESPHOME_PSTR("UNKNOWN");
   }
diff --git a/esphome/components/api/api_pb2_service.cpp b/esphome/components/api/api_pb2_service.cpp
index 6ae2a3e369..0ba2961a13 100644
--- a/esphome/components/api/api_pb2_service.cpp
+++ b/esphome/components/api/api_pb2_service.cpp
@@ -21,6 +21,7 @@ void APIServerConnectionBase::log_receive_message_(const LogString *name) {
 }
 #endif
 
+#ifdef USE_API
 void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const uint8_t *msg_data) {
   // Check authentication/connection requirements
   switch (msg_type) {
@@ -706,5 +707,6 @@ void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const ui
       break;
   }
 }
+#endif  // USE_API
 
 }  // namespace esphome::api
diff --git a/esphome/components/api/api_server.cpp b/esphome/components/api/api_server.cpp
index c30bd2e612..6c26c4e187 100644
--- a/esphome/components/api/api_server.cpp
+++ b/esphome/components/api/api_server.cpp
@@ -30,6 +30,11 @@ APIServer *global_api_server = nullptr;  // NOLINT(cppcoreguidelines-avoid-non-c
 
 APIServer::APIServer() { global_api_server = this; }
 
+// Custom deleter defined here so `delete` sees the complete APIConnection type.
+// This prevents libc++ from emitting an "incomplete type" error when other
+// translation units only have the forward declaration of APIConnection.
+void APIServer::APIConnectionDeleter::operator()(APIConnection *p) const { delete p; }
+
 void APIServer::socket_failed_(const LogString *msg) {
   ESP_LOGW(TAG, "Socket %s: errno %d", LOG_STR_ARG(msg), errno);
   this->destroy_socket_();
diff --git a/esphome/components/api/api_server.h b/esphome/components/api/api_server.h
index e662d78eba..6b575e536d 100644
--- a/esphome/components/api/api_server.h
+++ b/esphome/components/api/api_server.h
@@ -193,7 +193,13 @@ class APIServer final : public Component,
   // Range-for view over the populated slice [0, api_connection_count_). Read-only with respect
   // to ownership — callers get `const unique_ptr&` so they can invoke non-const methods on the
   // APIConnection but cannot reset/move the slot and break the count invariant.
-  using APIConnectionPtr = std::unique_ptr<APIConnection>;
+  // Custom deleter is defined out-of-line in api_server.cpp so libc++ does not
+  // eagerly instantiate `delete static_cast<APIConnection *>(p)` here, where
+  // only the forward declaration of APIConnection is visible (incomplete type).
+  struct APIConnectionDeleter {
+    void operator()(APIConnection *p) const;
+  };
+  using APIConnectionPtr = std::unique_ptr<APIConnection, APIConnectionDeleter>;
   class ActiveClientsView {
     const APIConnectionPtr *begin_;
     const APIConnectionPtr *end_;
@@ -292,7 +298,7 @@ class APIServer final : public Component,
   uint32_t last_connected_{0};
 
   // Slots [0, api_connection_count_) are populated; trailing slots are always nullptr.
-  std::array<std::unique_ptr<APIConnection>, MAX_API_CONNECTIONS> clients_{};
+  std::array<APIConnectionPtr, MAX_API_CONNECTIONS> clients_{};
   // Vectors and strings (12 bytes each on 32-bit)
   // Shared proto write buffer for all connections.
   // Not pre-allocated: all send paths call prepare_first_message_buffer() which
diff --git a/esphome/components/api/client.py b/esphome/components/api/client.py
index 312d937f01..d5214ccbf6 100644
--- a/esphome/components/api/client.py
+++ b/esphome/components/api/client.py
@@ -18,7 +18,7 @@ with warnings.catch_warnings():
 import contextlib
 
 from esphome.const import CONF_KEY, CONF_PORT, __version__
-from esphome.core import CORE
+from esphome.core import CORE, EsphomeError
 from esphome.platformio_api import process_stacktrace
 
 from . import CONF_ENCRYPTION
@@ -32,6 +32,52 @@ if TYPE_CHECKING:
 _LOGGER = logging.getLogger(__name__)
 
 
+class _LogLineProcessor:
+    """Feeds incoming log lines to the stack-trace decoder.
+
+    Two responsibilities beyond just calling the decoder:
+    1. Catch EsphomeError. on_log runs inside an asyncio protocol
+       callback; if an exception escapes, the loop tears the transport
+       down with "Fatal error: protocol.data_received() call failed."
+       and ReconnectLogic immediately reconnects, the device replays
+       the same crash trace, and we loop forever.
+    2. Disable decoding after the first failure. _decode_pc shells out
+       to PlatformIO via _run_idedata, which is expensive; a single
+       crash dump can contain many PC/BT lines and we don't want to
+       retry the failing subprocess for each one.
+    """
+
+    def __init__(self, config: dict[str, Any], platform_handler: Any | None) -> None:
+        self._config = config
+        self._platform_handler = platform_handler
+        self._decode_enabled = True
+        self.backtrace_state = False
+
+    def process_line(self, raw_line: str) -> None:
+        if not self._decode_enabled:
+            return
+        try:
+            if self._platform_handler is not None:
+                self.backtrace_state = self._platform_handler(
+                    self._config, raw_line, self.backtrace_state
+                )
+            else:
+                self.backtrace_state = process_stacktrace(
+                    self._config, raw_line, backtrace_state=self.backtrace_state
+                )
+        except EsphomeError as exc:
+            self._decode_enabled = False
+            self.backtrace_state = False
+            # _run_idedata raises EsphomeError with no message; fall back
+            # to a generic explanation when str(exc) is empty.
+            detail = str(exc) or "build artifacts not found locally"
+            _LOGGER.warning(
+                "Crash trace decoding unavailable: %s. "
+                "Run 'esphome compile' for this device to enable PC decoding.",
+                detail,
+            )
+
+
 async def async_run_logs(
     config: dict[str, Any],
     addresses: list[str],
@@ -61,7 +107,6 @@ async def async_run_logs(
         addresses=addresses,  # Pass all addresses for automatic retry
     )
     dashboard = CORE.dashboard
-    backtrace_state = False
 
     # Try platform-specific stacktrace handler first, fall back to generic
     platform_process_stacktrace = None
@@ -71,9 +116,10 @@ async def async_run_logs(
     except (AttributeError, ImportError):
         pass
 
+    processor = _LogLineProcessor(config, platform_process_stacktrace)
+
     def on_log(msg: SubscribeLogsResponse) -> None:
         """Handle a new log message."""
-        nonlocal backtrace_state
         time_ = datetime.now()
         message: bytes = msg.message
         text = message.decode("utf8", "backslashreplace")
@@ -84,14 +130,7 @@ async def async_run_logs(
         for parsed_msg in parse_log_message(text, timestamp):
             print(parsed_msg.replace("\033", "\\033") if dashboard else parsed_msg)
         for raw_line in text.splitlines():
-            if platform_process_stacktrace:
-                backtrace_state = platform_process_stacktrace(
-                    config, raw_line, backtrace_state
-                )
-            else:
-                backtrace_state = process_stacktrace(
-                    config, raw_line, backtrace_state=backtrace_state
-                )
+            processor.process_line(raw_line)
 
     # Safe to fall back to plaintext here only for this diagnostics use
     # case: the stream is one-way from device to client, and this code
diff --git a/esphome/components/api/homeassistant_service.h b/esphome/components/api/homeassistant_service.h
index 9d14061d07..aef046fbb0 100644
--- a/esphome/components/api/homeassistant_service.h
+++ b/esphome/components/api/homeassistant_service.h
@@ -78,7 +78,8 @@ class ActionResponse {
       : success_(success), error_message_(error_message) {
     if (data == nullptr || data_len == 0)
       return;
-    this->json_document_ = json::parse_json(data, data_len);
+    JsonDocument tmp = json::parse_json(data, data_len);
+    swap(this->json_document_, tmp);
   }
 #endif
 
diff --git a/esphome/components/api/proto.h b/esphome/components/api/proto.h
index 8cac7fff3b..f058f6af22 100644
--- a/esphome/components/api/proto.h
+++ b/esphome/components/api/proto.h
@@ -342,6 +342,32 @@ class ProtoEncode {
     }
     encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
   }
+  /// Encode a 48-bit MAC address (stored in a uint64) as varint.
+  /// Real MAC addresses occupy the full 48 bits (OUI in upper 24), so the
+  /// fast path -- any non-zero bit in the top 6 of 48 -- emits exactly 7 bytes
+  /// with no per-byte branch. Falls back to the general loop otherwise.
+  /// Caller must guarantee value fits in 48 bits (checked in debug builds).
+  static inline void ESPHOME_ALWAYS_INLINE encode_varint_raw_48bit(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
+                                                                   uint64_t value) {
+#ifdef ESPHOME_DEBUG_API
+    assert(value < (1ULL << (MAC_ADDRESS_SIZE * 8)) && "encode_varint_raw_48bit: value exceeds 48 bits");
+#endif
+    // 7-byte varint holds 49 bits (7 * 7), so a 48-bit value needs all 7 bytes
+    // whenever bit 42 or higher is set (i.e. value >= 1 << (48 - 6)).
+    if (value >= (1ULL << (MAC_ADDRESS_SIZE * 8 - 6))) [[likely]] {
+      PROTO_ENCODE_CHECK_BOUNDS(pos, 7);
+      pos[0] = static_cast<uint8_t>(value | 0x80);
+      pos[1] = static_cast<uint8_t>((value >> 7) | 0x80);
+      pos[2] = static_cast<uint8_t>((value >> 14) | 0x80);
+      pos[3] = static_cast<uint8_t>((value >> 21) | 0x80);
+      pos[4] = static_cast<uint8_t>((value >> 28) | 0x80);
+      pos[5] = static_cast<uint8_t>((value >> 35) | 0x80);
+      pos[6] = static_cast<uint8_t>(value >> 42);
+      pos += 7;
+      return;
+    }
+    encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, value);
+  }
   static inline void ESPHOME_ALWAYS_INLINE encode_field_raw(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
                                                             uint32_t field_id, uint32_t type) {
     encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, (field_id << 3) | type);
@@ -398,6 +424,7 @@ class ProtoEncode {
     if (len == 0 && !force)
       return;
     encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);  // type 2: Length-delimited string
+    // NOLINTNEXTLINE(readability-inconsistent-ifelse-braces) -- false positive on [[likely]] attribute
     if (len < VARINT_MAX_1_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1 + len);
       *pos++ = static_cast<uint8_t>(len);
@@ -817,6 +844,14 @@ class ProtoSize {
   static constexpr inline uint32_t ESPHOME_ALWAYS_INLINE calc_uint64_force(uint32_t field_id_size, uint64_t value) {
     return field_id_size + varint(value);
   }
+  /// 48-bit MAC address variant: matches encode_varint_raw_48bit's fast path.
+  /// When any of the top 6 of 48 bits is set the encoded varint is 7 bytes;
+  /// otherwise fall back to the general size calculation.
+  /// Caller must guarantee value fits in 48 bits (encoder asserts in debug).
+  static constexpr inline uint32_t ESPHOME_ALWAYS_INLINE calc_uint64_48bit_force(uint32_t field_id_size,
+                                                                                 uint64_t value) {
+    return field_id_size + (value >= (1ULL << (MAC_ADDRESS_SIZE * 8 - 6)) ? 7 : varint(value));
+  }
   static constexpr uint32_t calc_length(uint32_t field_id_size, size_t len) {
     return len ? field_id_size + varint(static_cast<uint32_t>(len)) + static_cast<uint32_t>(len) : 0;
   }
diff --git a/esphome/components/aqi/aqi_calculator.h b/esphome/components/aqi/aqi_calculator.h
index d624af0432..bb8e402280 100644
--- a/esphome/components/aqi/aqi_calculator.h
+++ b/esphome/components/aqi/aqi_calculator.h
@@ -14,11 +14,7 @@ class AQICalculator : public AbstractAQICalculator {
   uint16_t get_aqi(float pm2_5_value, float pm10_0_value) override {
     float pm2_5_index = calculate_index(pm2_5_value, PM2_5_GRID);
     float pm10_0_index = calculate_index(pm10_0_value, PM10_0_GRID);
-
-    float aqi = std::max(pm2_5_index, pm10_0_index);
-    if (aqi < 0.0f) {
-      aqi = 0.0f;
-    }
+    float aqi = std::max({pm2_5_index, pm10_0_index, 0.0f});
     return static_cast<uint16_t>(std::lround(aqi));
   }
 
diff --git a/esphome/components/aqi/caqi_calculator.h b/esphome/components/aqi/caqi_calculator.h
index fe2efe7059..3f6da45aa9 100644
--- a/esphome/components/aqi/caqi_calculator.h
+++ b/esphome/components/aqi/caqi_calculator.h
@@ -12,11 +12,7 @@ class CAQICalculator : public AbstractAQICalculator {
   uint16_t get_aqi(float pm2_5_value, float pm10_0_value) override {
     float pm2_5_index = calculate_index(pm2_5_value, PM2_5_GRID);
     float pm10_0_index = calculate_index(pm10_0_value, PM10_0_GRID);
-
-    float aqi = std::max(pm2_5_index, pm10_0_index);
-    if (aqi < 0.0f) {
-      aqi = 0.0f;
-    }
+    float aqi = std::max({pm2_5_index, pm10_0_index, 0.0f});
     return static_cast<uint16_t>(std::lround(aqi));
   }
 
diff --git a/esphome/components/audio/__init__.py b/esphome/components/audio/__init__.py
index fe111be31e..8528e77ae7 100644
--- a/esphome/components/audio/__init__.py
+++ b/esphome/components/audio/__init__.py
@@ -1,4 +1,4 @@
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 
 import esphome.codegen as cg
 from esphome.components.esp32 import (
@@ -7,7 +7,12 @@ from esphome.components.esp32 import (
     include_builtin_idf_component,
 )
 import esphome.config_validation as cv
-from esphome.const import CONF_BITS_PER_SAMPLE, CONF_NUM_CHANNELS, CONF_SAMPLE_RATE
+from esphome.const import (
+    CONF_BITS_PER_SAMPLE,
+    CONF_NUM_CHANNELS,
+    CONF_SAMPLE_RATE,
+    CONF_SIZE,
+)
 from esphome.core import CORE
 import esphome.final_validate as fv
 
@@ -25,13 +30,46 @@ AUDIO_FILE_TYPE_ENUM = {
     "OPUS": AudioFileType.OPUS,
 }
 
+MEMORY_PSRAM = "psram"
+MEMORY_INTERNAL = "internal"
+MEMORY_LOCATIONS = [MEMORY_PSRAM, MEMORY_INTERNAL]
+
+
+@dataclass
+class FlacOptions:
+    buffer_memory: str | None = None
+
+
+@dataclass
+class Mp3Options:
+    buffer_memory: str | None = None
+
+
+@dataclass
+class OpusPseudostackOptions:
+    threadsafe: bool | None = None
+    buffer_memory: str | None = None
+    size: int | None = None
+
+
+@dataclass
+class OpusOptions:
+    floating_point: bool | None = None
+    state_memory: str | None = None
+    pseudostack: OpusPseudostackOptions = field(default_factory=OpusPseudostackOptions)
+
 
 @dataclass
 class AudioData:
     flac_support: bool = False
     mp3_support: bool = False
     opus_support: bool = False
+    # WAV defaults to True for backward compatibility; will become opt-in in a future release
+    wav_support: bool = True
     micro_decoder_support: bool = False
+    flac: FlacOptions = field(default_factory=FlacOptions)
+    mp3: Mp3Options = field(default_factory=Mp3Options)
+    opus: OpusOptions = field(default_factory=OpusOptions)
 
 
 def _get_data() -> AudioData:
@@ -55,6 +93,11 @@ def request_opus_support() -> None:
     _get_data().opus_support = True
 
 
+def request_wav_support() -> None:
+    """Request WAV codec support for audio decoding."""
+    _get_data().wav_support = True
+
+
 def request_micro_decoder_support() -> None:
     """Request micro-decoder library support for audio decoding."""
     _get_data().micro_decoder_support = True
@@ -67,9 +110,78 @@ CONF_MAX_CHANNELS = "max_channels"
 CONF_MIN_SAMPLE_RATE = "min_sample_rate"
 CONF_MAX_SAMPLE_RATE = "max_sample_rate"
 
+CONF_CODECS = "codecs"
+CONF_WAV = "wav"
+CONF_FLAC = "flac"
+CONF_MP3 = "mp3"
+CONF_OPUS = "opus"
+CONF_BUFFER_MEMORY = "buffer_memory"
+CONF_FLOATING_POINT = "floating_point"
+CONF_STATE_MEMORY = "state_memory"
+CONF_PSEUDOSTACK = "pseudostack"
+CONF_THREADSAFE = "threadsafe"
+
+
+_MEMORY_LOCATION_VALIDATOR = cv.one_of(*MEMORY_LOCATIONS, lower=True)
+
+
+def _maybe_empty_codec(schema):
+    """Wrap a codec dict schema so that a bare key (None value) is treated as an empty dict."""
+
+    def validator(value):
+        if value is None:
+            value = {}
+        return schema(value)
+
+    return validator
+
+
+CODEC_FLAC_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_BUFFER_MEMORY): _MEMORY_LOCATION_VALIDATOR,
+    }
+)
+
+CODEC_MP3_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_BUFFER_MEMORY): _MEMORY_LOCATION_VALIDATOR,
+    }
+)
+
+OPUS_PSEUDOSTACK_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_THREADSAFE): cv.boolean,
+        cv.Optional(CONF_BUFFER_MEMORY): _MEMORY_LOCATION_VALIDATOR,
+        cv.Optional(CONF_SIZE): cv.int_range(60000, 240000),
+    }
+)
+
+CODEC_OPUS_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_FLOATING_POINT): cv.boolean,
+        cv.Optional(CONF_STATE_MEMORY): _MEMORY_LOCATION_VALIDATOR,
+        cv.Optional(CONF_PSEUDOSTACK): _maybe_empty_codec(OPUS_PSEUDOSTACK_SCHEMA),
+    }
+)
+
+CODEC_WAV_SCHEMA = cv.Schema({})
+
+CODECS_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_FLAC): _maybe_empty_codec(CODEC_FLAC_SCHEMA),
+        cv.Optional(CONF_MP3): _maybe_empty_codec(CODEC_MP3_SCHEMA),
+        cv.Optional(CONF_OPUS): _maybe_empty_codec(CODEC_OPUS_SCHEMA),
+        cv.Optional(CONF_WAV): _maybe_empty_codec(CODEC_WAV_SCHEMA),
+    }
+)
 
 CONFIG_SCHEMA = cv.All(
-    cv.Schema({}),
+    cv.Schema(
+        {
+            cv.Optional(CONF_CODECS): _maybe_empty_codec(CODECS_SCHEMA),
+        }
+    ),
+    cv.only_on_esp32,
 )
 
 AUDIO_COMPONENT_SCHEMA = cv.Schema(
@@ -208,6 +320,15 @@ def final_validate_audio_schema(
     )
 
 
+def _emit_memory_pair(value: str | None, psram_key: str, internal_key: str) -> None:
+    if value == MEMORY_PSRAM:
+        add_idf_sdkconfig_option(psram_key, True)
+        add_idf_sdkconfig_option(internal_key, False)
+    elif value == MEMORY_INTERNAL:
+        add_idf_sdkconfig_option(psram_key, False)
+        add_idf_sdkconfig_option(internal_key, True)
+
+
 async def to_code(config):
     # Re-enable ESP-IDF's HTTP client (excluded by default to save compile time)
     include_builtin_idf_component("esp_http_client")
@@ -219,6 +340,36 @@ async def to_code(config):
 
     data = _get_data()
 
+    # Merge user-supplied codec configuration (additive: presence enables the codec)
+    if codecs_config := config.get(CONF_CODECS):
+        if (flac_config := codecs_config.get(CONF_FLAC)) is not None:
+            data.flac_support = True
+            if (buffer_memory := flac_config.get(CONF_BUFFER_MEMORY)) is not None:
+                data.flac.buffer_memory = buffer_memory
+        if (mp3_config := codecs_config.get(CONF_MP3)) is not None:
+            data.mp3_support = True
+            if (buffer_memory := mp3_config.get(CONF_BUFFER_MEMORY)) is not None:
+                data.mp3.buffer_memory = buffer_memory
+        if (opus_config := codecs_config.get(CONF_OPUS)) is not None:
+            data.opus_support = True
+            floating_point = opus_config.get(CONF_FLOATING_POINT)
+            if floating_point is not None:
+                data.opus.floating_point = floating_point
+            if (state_memory := opus_config.get(CONF_STATE_MEMORY)) is not None:
+                data.opus.state_memory = state_memory
+            if (pseudostack_config := opus_config.get(CONF_PSEUDOSTACK)) is not None:
+                threadsafe = pseudostack_config.get(CONF_THREADSAFE)
+                if threadsafe is not None:
+                    data.opus.pseudostack.threadsafe = threadsafe
+                if (
+                    buffer_memory := pseudostack_config.get(CONF_BUFFER_MEMORY)
+                ) is not None:
+                    data.opus.pseudostack.buffer_memory = buffer_memory
+                if (size := pseudostack_config.get(CONF_SIZE)) is not None:
+                    data.opus.pseudostack.size = size
+        if CONF_WAV in codecs_config:
+            data.wav_support = True
+
     if data.micro_decoder_support:
         add_idf_component(name="esphome/micro-decoder", ref="0.2.0")
 
@@ -229,13 +380,50 @@ async def to_code(config):
             add_idf_sdkconfig_option("CONFIG_MICRO_DECODER_CODEC_MP3", False)
         if not data.opus_support:
             add_idf_sdkconfig_option("CONFIG_MICRO_DECODER_CODEC_OPUS", False)
+        if not data.wav_support:
+            add_idf_sdkconfig_option("CONFIG_MICRO_DECODER_CODEC_WAV", False)
 
-    # Legacy audio_decoder.cpp support defines and components
+    # Configure each codec library.
+    # Adds a define and IDF component for legacy `audio_decoder.cpp`.
     if data.flac_support:
         cg.add_define("USE_AUDIO_FLAC_SUPPORT")
         add_idf_component(name="esphome/micro-flac", ref="0.1.1")
+        _emit_memory_pair(
+            data.flac.buffer_memory,
+            "CONFIG_MICRO_FLAC_PREFER_PSRAM",
+            "CONFIG_MICRO_FLAC_PREFER_INTERNAL",
+        )
     if data.mp3_support:
         cg.add_define("USE_AUDIO_MP3_SUPPORT")
+        _emit_memory_pair(
+            data.mp3.buffer_memory,
+            "CONFIG_MP3_DECODER_PREFER_PSRAM",
+            "CONFIG_MP3_DECODER_PREFER_INTERNAL",
+        )
     if data.opus_support:
         cg.add_define("USE_AUDIO_OPUS_SUPPORT")
-        add_idf_component(name="esphome/micro-opus", ref="0.3.6")
+        add_idf_component(name="esphome/micro-opus", ref="0.4.0")
+        if data.opus.floating_point is not None:
+            add_idf_sdkconfig_option(
+                "CONFIG_OPUS_FLOATING_POINT", data.opus.floating_point
+            )
+        _emit_memory_pair(
+            data.opus.state_memory,
+            "CONFIG_OPUS_STATE_PREFER_PSRAM",
+            "CONFIG_OPUS_STATE_PREFER_INTERNAL",
+        )
+        if data.opus.pseudostack.threadsafe is True:
+            add_idf_sdkconfig_option("CONFIG_OPUS_THREADSAFE_PSEUDOSTACK", True)
+            add_idf_sdkconfig_option("CONFIG_OPUS_NONTHREADSAFE_PSEUDOSTACK", False)
+        elif data.opus.pseudostack.threadsafe is False:
+            add_idf_sdkconfig_option("CONFIG_OPUS_THREADSAFE_PSEUDOSTACK", False)
+            add_idf_sdkconfig_option("CONFIG_OPUS_NONTHREADSAFE_PSEUDOSTACK", True)
+        _emit_memory_pair(
+            data.opus.pseudostack.buffer_memory,
+            "CONFIG_OPUS_PSEUDOSTACK_PREFER_PSRAM",
+            "CONFIG_OPUS_PSEUDOSTACK_PREFER_INTERNAL",
+        )
+        if data.opus.pseudostack.size is not None:
+            add_idf_sdkconfig_option(
+                "CONFIG_OPUS_PSEUDOSTACK_SIZE", data.opus.pseudostack.size
+            )
diff --git a/esphome/components/audio_file/__init__.py b/esphome/components/audio_file/__init__.py
index bb1ce257db..88be6db168 100644
--- a/esphome/components/audio_file/__init__.py
+++ b/esphome/components/audio_file/__init__.py
@@ -1,4 +1,5 @@
 from dataclasses import dataclass, field
+from functools import partial
 import hashlib
 import logging
 from pathlib import Path
@@ -19,7 +20,7 @@ from esphome.const import (
 )
 from esphome.core import CORE, ID, HexInt
 from esphome.cpp_generator import MockObj
-from esphome.external_files import download_content
+from esphome.external_files import download_web_files_in_config
 from esphome.types import ConfigType
 
 _LOGGER = logging.getLogger(__name__)
@@ -63,15 +64,6 @@ def _compute_local_file_path(value: ConfigType) -> Path:
     return base_dir / key
 
 
-def _download_web_file(value: ConfigType) -> ConfigType:
-    url = value[CONF_URL]
-    path = _compute_local_file_path(value)
-
-    download_content(url, path)
-    _LOGGER.debug("download_web_file: path=%s", path)
-    return value
-
-
 def _file_schema(value: ConfigType | str) -> ConfigType:
     if isinstance(value, str):
         return _validate_file_shorthand(value)
@@ -142,11 +134,10 @@ LOCAL_SCHEMA = cv.Schema(
     }
 )
 
-WEB_SCHEMA = cv.All(
+WEB_SCHEMA = cv.Schema(
     {
         cv.Required(CONF_URL): cv.url,
-    },
-    _download_web_file,
+    }
 )
 
 
@@ -209,6 +200,7 @@ def _validate_supported_local_file(config: list[ConfigType]) -> list[ConfigType]
 CONFIG_SCHEMA = cv.All(
     cv.only_on_esp32,
     cv.ensure_list(MEDIA_FILE_TYPE_SCHEMA),
+    partial(download_web_files_in_config, path_for=_compute_local_file_path),
     _validate_supported_local_file,
 )
 
diff --git a/esphome/components/beken_spi_led_strip/light.py b/esphome/components/beken_spi_led_strip/light.py
index 31572cd800..9093b08b62 100644
--- a/esphome/components/beken_spi_led_strip/light.py
+++ b/esphome/components/beken_spi_led_strip/light.py
@@ -62,6 +62,7 @@ CONF_IS_WRGB = "is_wrgb"
 SUPPORTED_PINS = {
     libretiny.const.FAMILY_BK7231N: [16],
     libretiny.const.FAMILY_BK7231T: [16],
+    libretiny.const.FAMILY_BK7238: [16],
     libretiny.const.FAMILY_BK7251: [16],
 }
 
diff --git a/esphome/components/binary_sensor/__init__.py b/esphome/components/binary_sensor/__init__.py
index 1456e5bc66..a9a09363fc 100644
--- a/esphome/components/binary_sensor/__init__.py
+++ b/esphome/components/binary_sensor/__init__.py
@@ -143,15 +143,15 @@ BinarySensorCondition = binary_sensor_ns.class_("BinarySensorCondition", Conditi
 
 # Filters
 Filter = binary_sensor_ns.class_("Filter")
-TimeoutFilter = binary_sensor_ns.class_("TimeoutFilter", Filter, cg.Component)
-DelayedOnOffFilter = binary_sensor_ns.class_("DelayedOnOffFilter", Filter, cg.Component)
-DelayedOnFilter = binary_sensor_ns.class_("DelayedOnFilter", Filter, cg.Component)
-DelayedOffFilter = binary_sensor_ns.class_("DelayedOffFilter", Filter, cg.Component)
+TimeoutFilter = binary_sensor_ns.class_("TimeoutFilter", Filter)
+DelayedOnOffFilter = binary_sensor_ns.class_("DelayedOnOffFilter", Filter)
+DelayedOnFilter = binary_sensor_ns.class_("DelayedOnFilter", Filter)
+DelayedOffFilter = binary_sensor_ns.class_("DelayedOffFilter", Filter)
 InvertFilter = binary_sensor_ns.class_("InvertFilter", Filter)
-AutorepeatFilter = binary_sensor_ns.class_("AutorepeatFilter", Filter, cg.Component)
+AutorepeatFilter = binary_sensor_ns.class_("AutorepeatFilter", Filter)
 LambdaFilter = binary_sensor_ns.class_("LambdaFilter", Filter)
 StatelessLambdaFilter = binary_sensor_ns.class_("StatelessLambdaFilter", Filter)
-SettleFilter = binary_sensor_ns.class_("SettleFilter", Filter, cg.Component)
+SettleFilter = binary_sensor_ns.class_("SettleFilter", Filter)
 
 _LOGGER = getLogger(__name__)
 
@@ -175,7 +175,6 @@ async def invert_filter_to_code(config, filter_id):
 )
 async def timeout_filter_to_code(config, filter_id):
     var = cg.new_Pvariable(filter_id)
-    await cg.register_component(var, {})
     template_ = await cg.templatable(config, [], cg.uint32)
     cg.add(var.set_timeout_value(template_))
     return var
@@ -203,7 +202,6 @@ async def timeout_filter_to_code(config, filter_id):
 )
 async def delayed_on_off_filter_to_code(config, filter_id):
     var = cg.new_Pvariable(filter_id)
-    await cg.register_component(var, {})
     if isinstance(config, dict):
         template_ = await cg.templatable(config[CONF_TIME_ON], [], cg.uint32)
         cg.add(var.set_on_delay(template_))
@@ -221,7 +219,6 @@ async def delayed_on_off_filter_to_code(config, filter_id):
 )
 async def delayed_on_filter_to_code(config, filter_id):
     var = cg.new_Pvariable(filter_id)
-    await cg.register_component(var, {})
     template_ = await cg.templatable(config, [], cg.uint32)
     cg.add(var.set_delay(template_))
     return var
@@ -234,7 +231,6 @@ async def delayed_on_filter_to_code(config, filter_id):
 )
 async def delayed_off_filter_to_code(config, filter_id):
     var = cg.new_Pvariable(filter_id)
-    await cg.register_component(var, {})
     template_ = await cg.templatable(config, [], cg.uint32)
     cg.add(var.set_delay(template_))
     return var
@@ -286,9 +282,7 @@ async def autorepeat_filter_to_code(config, filter_id):
                 ),
             )
         ]
-    var = cg.new_Pvariable(filter_id, cg.TemplateArguments(len(timings)), timings)
-    await cg.register_component(var, {})
-    return var
+    return cg.new_Pvariable(filter_id, cg.TemplateArguments(len(timings)), timings)
 
 
 @register_filter("lambda", LambdaFilter, cv.returning_lambda)
@@ -306,7 +300,6 @@ async def lambda_filter_to_code(config, filter_id):
 )
 async def settle_filter_to_code(config, filter_id):
     var = cg.new_Pvariable(filter_id)
-    await cg.register_component(var, {})
     template_ = await cg.templatable(config, [], cg.uint32)
     cg.add(var.set_delay(template_))
     return var
diff --git a/esphome/components/binary_sensor/automation.cpp b/esphome/components/binary_sensor/automation.cpp
index eb68abce3b..b13e4a88dd 100644
--- a/esphome/components/binary_sensor/automation.cpp
+++ b/esphome/components/binary_sensor/automation.cpp
@@ -50,29 +50,31 @@ void MultiClickTriggerBase::on_state_(bool state) {
     return;
   }
 
-  if (*this->at_index_ == this->timing_count_) {
+  // at_index_ has a value here (the !has_value() branch above returns).
+  size_t at_index = *this->at_index_;
+  if (at_index == this->timing_count_) {
     this->trigger_();
     return;
   }
 
-  MultiClickTriggerEvent evt = this->timing_[*this->at_index_];
+  MultiClickTriggerEvent evt = this->timing_[at_index];
 
   if (evt.max_length != 4294967294UL) {
-    ESP_LOGV(TAG, "A i=%zu min=%" PRIu32 " max=%" PRIu32, *this->at_index_, evt.min_length, evt.max_length);  // NOLINT
+    ESP_LOGV(TAG, "A i=%zu min=%" PRIu32 " max=%" PRIu32, at_index, evt.min_length, evt.max_length);  // NOLINT
     this->schedule_is_valid_(evt.min_length);
     this->schedule_is_not_valid_(evt.max_length);
-  } else if (*this->at_index_ + 1 != this->timing_count_) {
-    ESP_LOGV(TAG, "B i=%zu min=%" PRIu32, *this->at_index_, evt.min_length);  // NOLINT
+  } else if (at_index + 1 != this->timing_count_) {
+    ESP_LOGV(TAG, "B i=%zu min=%" PRIu32, at_index, evt.min_length);  // NOLINT
     this->cancel_timeout(MULTICLICK_IS_NOT_VALID_ID);
     this->schedule_is_valid_(evt.min_length);
   } else {
-    ESP_LOGV(TAG, "C i=%zu min=%" PRIu32, *this->at_index_, evt.min_length);  // NOLINT
+    ESP_LOGV(TAG, "C i=%zu min=%" PRIu32, at_index, evt.min_length);  // NOLINT
     this->is_valid_ = false;
     this->cancel_timeout(MULTICLICK_IS_NOT_VALID_ID);
     this->set_timeout(MULTICLICK_TRIGGER_ID, evt.min_length, [this]() { this->trigger_(); });
   }
 
-  *this->at_index_ = *this->at_index_ + 1;
+  this->at_index_ = at_index + 1;
 }
 void MultiClickTriggerBase::schedule_cooldown_() {
   ESP_LOGV(TAG, "Multi Click: Invalid length of press, starting cooldown of %" PRIu32 " ms", this->invalid_cooldown_);
diff --git a/esphome/components/binary_sensor/filter.cpp b/esphome/components/binary_sensor/filter.cpp
index 914060ce13..8b882212c8 100644
--- a/esphome/components/binary_sensor/filter.cpp
+++ b/esphome/components/binary_sensor/filter.cpp
@@ -4,19 +4,12 @@
 #include "filter.h"
 
 #include "binary_sensor.h"
+#include "esphome/core/application.h"
 
 namespace esphome::binary_sensor {
 
 static const char *const TAG = "sensor.filter";
 
-// Timeout IDs for filter classes.
-// Each filter is its own Component instance, so the scheduler scopes
-// IDs by component pointer — no risk of collisions between instances.
-constexpr uint32_t FILTER_TIMEOUT_ID = 0;
-// AutorepeatFilter needs two distinct IDs (both timeouts on the same component)
-constexpr uint32_t AUTOREPEAT_TIMING_ID = 0;
-constexpr uint32_t AUTOREPEAT_ON_OFF_ID = 1;
-
 void Filter::output(bool value) {
   if (this->next_ == nullptr) {
     this->parent_->send_state_internal(value);
@@ -34,49 +27,47 @@ void Filter::input(bool value) {
 }
 
 void TimeoutFilter::input(bool value) {
-  this->set_timeout(FILTER_TIMEOUT_ID, this->timeout_delay_.value(), [this]() { this->parent_->invalidate_state(); });
+  App.scheduler.set_timeout(this, this->timeout_delay_.value(), [this]() { this->parent_->invalidate_state(); });
   // we do not de-dup here otherwise changes from invalid to valid state will not be output
   this->output(value);
 }
 
 optional<bool> DelayedOnOffFilter::new_value(bool value) {
   if (value) {
-    this->set_timeout(FILTER_TIMEOUT_ID, this->on_delay_.value(), [this]() { this->output(true); });
+    App.scheduler.set_timeout(this, this->on_delay_.value(), [this]() { this->output(true); });
   } else {
-    this->set_timeout(FILTER_TIMEOUT_ID, this->off_delay_.value(), [this]() { this->output(false); });
+    App.scheduler.set_timeout(this, this->off_delay_.value(), [this]() { this->output(false); });
   }
   return {};
 }
 
-float DelayedOnOffFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 optional<bool> DelayedOnFilter::new_value(bool value) {
   if (value) {
-    this->set_timeout(FILTER_TIMEOUT_ID, this->delay_.value(), [this]() { this->output(true); });
+    App.scheduler.set_timeout(this, this->delay_.value(), [this]() { this->output(true); });
     return {};
   } else {
-    this->cancel_timeout(FILTER_TIMEOUT_ID);
+    App.scheduler.cancel_timeout(this);
     return false;
   }
 }
 
-float DelayedOnFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 optional<bool> DelayedOffFilter::new_value(bool value) {
   if (!value) {
-    this->set_timeout(FILTER_TIMEOUT_ID, this->delay_.value(), [this]() { this->output(false); });
+    App.scheduler.set_timeout(this, this->delay_.value(), [this]() { this->output(false); });
     return {};
   } else {
-    this->cancel_timeout(FILTER_TIMEOUT_ID);
+    App.scheduler.cancel_timeout(this);
     return true;
   }
 }
 
-float DelayedOffFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 optional<bool> InvertFilter::new_value(bool value) { return !value; }
 
 // AutorepeatFilterBase
+// Two independent timers per instance, keyed off two stable addresses inside
+// the filter: `this` for the timing-step timer, `&active_timing_` for the
+// on/off timer. Both are unique per instance and don't collide with anything
+// else, so the self-keyed scheduler API is sufficient.
 optional<bool> AutorepeatFilterBase::new_value(bool value) {
   if (value) {
     if (this->active_timing_ != 0)
@@ -84,8 +75,8 @@ optional<bool> AutorepeatFilterBase::new_value(bool value) {
     this->next_timing_();
     return true;
   } else {
-    this->cancel_timeout(AUTOREPEAT_TIMING_ID);
-    this->cancel_timeout(AUTOREPEAT_ON_OFF_ID);
+    App.scheduler.cancel_timeout(this);
+    App.scheduler.cancel_timeout(&this->active_timing_);
     this->active_timing_ = 0;
     return false;
   }
@@ -93,8 +84,7 @@ optional<bool> AutorepeatFilterBase::new_value(bool value) {
 
 void AutorepeatFilterBase::next_timing_() {
   if (this->active_timing_ < this->timings_count_) {
-    this->set_timeout(AUTOREPEAT_TIMING_ID, this->timings_[this->active_timing_].delay,
-                      [this]() { this->next_timing_(); });
+    App.scheduler.set_timeout(this, this->timings_[this->active_timing_].delay, [this]() { this->next_timing_(); });
   }
   if (this->active_timing_ <= this->timings_count_) {
     this->active_timing_++;
@@ -106,32 +96,28 @@ void AutorepeatFilterBase::next_timing_() {
 void AutorepeatFilterBase::next_value_(bool val) {
   const AutorepeatFilterTiming &timing = this->timings_[this->active_timing_ - 2];
   this->output(val);
-  this->set_timeout(AUTOREPEAT_ON_OFF_ID, val ? timing.time_on : timing.time_off,
-                    [this, val]() { this->next_value_(!val); });
+  App.scheduler.set_timeout(&this->active_timing_, val ? timing.time_on : timing.time_off,
+                            [this, val]() { this->next_value_(!val); });
 }
 
-float AutorepeatFilterBase::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 LambdaFilter::LambdaFilter(std::function<optional<bool>(bool)> f) : f_(std::move(f)) {}
 
 optional<bool> LambdaFilter::new_value(bool value) { return this->f_(value); }
 
 optional<bool> SettleFilter::new_value(bool value) {
   if (!this->steady_) {
-    this->set_timeout(FILTER_TIMEOUT_ID, this->delay_.value(), [this, value]() {
+    App.scheduler.set_timeout(this, this->delay_.value(), [this, value]() {
       this->steady_ = true;
       this->output(value);
     });
     return {};
   } else {
     this->steady_ = false;
-    this->set_timeout(FILTER_TIMEOUT_ID, this->delay_.value(), [this]() { this->steady_ = true; });
+    App.scheduler.set_timeout(this, this->delay_.value(), [this]() { this->steady_ = true; });
     return value;
   }
 }
 
-float SettleFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 }  // namespace esphome::binary_sensor
 
 #endif  // USE_BINARY_SENSOR_FILTER
diff --git a/esphome/components/binary_sensor/filter.h b/esphome/components/binary_sensor/filter.h
index 2e45554f81..6887de35e1 100644
--- a/esphome/components/binary_sensor/filter.h
+++ b/esphome/components/binary_sensor/filter.h
@@ -29,7 +29,7 @@ class Filter {
   Deduplicator<bool> dedup_;
 };
 
-class TimeoutFilter : public Filter, public Component {
+class TimeoutFilter : public Filter {
  public:
   optional<bool> new_value(bool value) override { return value; }
   void input(bool value) override;
@@ -39,12 +39,10 @@ class TimeoutFilter : public Filter, public Component {
   TemplatableFn<uint32_t> timeout_delay_{};
 };
 
-class DelayedOnOffFilter final : public Filter, public Component {
+class DelayedOnOffFilter final : public Filter {
  public:
   optional<bool> new_value(bool value) override;
 
-  float get_setup_priority() const override;
-
   template<typename T> void set_on_delay(T delay) { this->on_delay_ = delay; }
   template<typename T> void set_off_delay(T delay) { this->off_delay_ = delay; }
 
@@ -53,24 +51,20 @@ class DelayedOnOffFilter final : public Filter, public Component {
   TemplatableFn<uint32_t> off_delay_{};
 };
 
-class DelayedOnFilter : public Filter, public Component {
+class DelayedOnFilter : public Filter {
  public:
   optional<bool> new_value(bool value) override;
 
-  float get_setup_priority() const override;
-
   template<typename T> void set_delay(T delay) { this->delay_ = delay; }
 
  protected:
   TemplatableFn<uint32_t> delay_{};
 };
 
-class DelayedOffFilter : public Filter, public Component {
+class DelayedOffFilter : public Filter {
  public:
   optional<bool> new_value(bool value) override;
 
-  float get_setup_priority() const override;
-
   template<typename T> void set_delay(T delay) { this->delay_ = delay; }
 
  protected:
@@ -90,10 +84,11 @@ struct AutorepeatFilterTiming {
 
 /// Non-template base for AutorepeatFilter — all methods in filter.cpp.
 /// Lambdas capture this base pointer, so set_timeout/cancel_timeout are instantiated once.
-class AutorepeatFilterBase : public Filter, public Component {
+/// The two scheduled timers are keyed off `this` and `&active_timing_`; since the address
+/// of `active_timing_` is taken as a scheduler key, the class must not be copied or moved.
+class AutorepeatFilterBase : public Filter {
  public:
   optional<bool> new_value(bool value) override;
-  float get_setup_priority() const override;
   AutorepeatFilterBase(const AutorepeatFilterBase &) = delete;
   AutorepeatFilterBase &operator=(const AutorepeatFilterBase &) = delete;
 
@@ -146,12 +141,10 @@ class StatelessLambdaFilter : public Filter {
   optional<bool> (*f_)(bool);
 };
 
-class SettleFilter : public Filter, public Component {
+class SettleFilter : public Filter {
  public:
   optional<bool> new_value(bool value) override;
 
-  float get_setup_priority() const override;
-
   template<typename T> void set_delay(T delay) { this->delay_ = delay; }
 
  protected:
diff --git a/esphome/components/bme680/bme680.cpp b/esphome/components/bme680/bme680.cpp
index e3cd80de00..b599d64c0d 100644
--- a/esphome/components/bme680/bme680.cpp
+++ b/esphome/components/bme680/bme680.cpp
@@ -78,43 +78,43 @@ void BME680Component::setup() {
   }
 
   // Read calibration
-  uint8_t cal1[25];
-  if (!this->read_bytes(BME680_REGISTER_COEFF1, cal1, 25)) {
+  uint8_t coeff1[25];
+  if (!this->read_bytes(BME680_REGISTER_COEFF1, coeff1, 25)) {
     this->mark_failed();
     return;
   }
-  uint8_t cal2[16];
-  if (!this->read_bytes(BME680_REGISTER_COEFF2, cal2, 16)) {
+  uint8_t coeff2[16];
+  if (!this->read_bytes(BME680_REGISTER_COEFF2, coeff2, 16)) {
     this->mark_failed();
     return;
   }
 
-  this->calibration_.t1 = cal2[9] << 8 | cal2[8];
-  this->calibration_.t2 = cal1[2] << 8 | cal1[1];
-  this->calibration_.t3 = cal1[3];
+  this->calibration_.t1 = coeff2[9] << 8 | coeff2[8];
+  this->calibration_.t2 = coeff1[2] << 8 | coeff1[1];
+  this->calibration_.t3 = coeff1[3];
 
-  this->calibration_.h1 = cal2[2] << 4 | (cal2[1] & 0x0F);
-  this->calibration_.h2 = cal2[0] << 4 | cal2[1] >> 4;
-  this->calibration_.h3 = cal2[3];
-  this->calibration_.h4 = cal2[4];
-  this->calibration_.h5 = cal2[5];
-  this->calibration_.h6 = cal2[6];
-  this->calibration_.h7 = cal2[7];
+  this->calibration_.h1 = coeff2[2] << 4 | (coeff2[1] & 0x0F);
+  this->calibration_.h2 = coeff2[0] << 4 | coeff2[1] >> 4;
+  this->calibration_.h3 = coeff2[3];
+  this->calibration_.h4 = coeff2[4];
+  this->calibration_.h5 = coeff2[5];
+  this->calibration_.h6 = coeff2[6];
+  this->calibration_.h7 = coeff2[7];
 
-  this->calibration_.p1 = cal1[6] << 8 | cal1[5];
-  this->calibration_.p2 = cal1[8] << 8 | cal1[7];
-  this->calibration_.p3 = cal1[9];
-  this->calibration_.p4 = cal1[12] << 8 | cal1[11];
-  this->calibration_.p5 = cal1[14] << 8 | cal1[13];
-  this->calibration_.p6 = cal1[16];
-  this->calibration_.p7 = cal1[15];
-  this->calibration_.p8 = cal1[20] << 8 | cal1[19];
-  this->calibration_.p9 = cal1[22] << 8 | cal1[21];
-  this->calibration_.p10 = cal1[23];
+  this->calibration_.p1 = coeff1[6] << 8 | coeff1[5];
+  this->calibration_.p2 = coeff1[8] << 8 | coeff1[7];
+  this->calibration_.p3 = coeff1[9];
+  this->calibration_.p4 = coeff1[12] << 8 | coeff1[11];
+  this->calibration_.p5 = coeff1[14] << 8 | coeff1[13];
+  this->calibration_.p6 = coeff1[16];
+  this->calibration_.p7 = coeff1[15];
+  this->calibration_.p8 = coeff1[20] << 8 | coeff1[19];
+  this->calibration_.p9 = coeff1[22] << 8 | coeff1[21];
+  this->calibration_.p10 = coeff1[23];
 
-  this->calibration_.gh1 = cal2[14];
-  this->calibration_.gh2 = cal2[12] << 8 | cal2[13];
-  this->calibration_.gh3 = cal2[15];
+  this->calibration_.gh1 = coeff2[14];
+  this->calibration_.gh2 = coeff2[12] << 8 | coeff2[13];
+  this->calibration_.gh3 = coeff2[15];
 
   uint8_t temp_var = 0;
   if (!this->read_byte(0x02, &temp_var)) {
diff --git a/esphome/components/climate/__init__.py b/esphome/components/climate/__init__.py
index 0fdb18a92c..fc1b0f368e 100644
--- a/esphome/components/climate/__init__.py
+++ b/esphome/components/climate/__init__.py
@@ -48,13 +48,13 @@ from esphome.const import (
     CONF_VISUAL,
     CONF_WEB_SERVER,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, Lambda, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
     queue_entity_register,
     setup_entity,
 )
-from esphome.cpp_generator import MockObjClass
+from esphome.cpp_generator import LambdaExpression, MockObjClass
 
 IS_PLATFORM_COMPONENT = True
 
@@ -487,38 +487,65 @@ CLIMATE_CONTROL_ACTION_SCHEMA = cv.Schema(
 )
 async def climate_control_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if (mode := config.get(CONF_MODE)) is not None:
-        template_ = await cg.templatable(mode, args, ClimateMode)
-        cg.add(var.set_mode(template_))
-    if (target_temp := config.get(CONF_TARGET_TEMPERATURE)) is not None:
-        template_ = await cg.templatable(target_temp, args, cg.float_)
-        cg.add(var.set_target_temperature(template_))
-    if (target_temp_low := config.get(CONF_TARGET_TEMPERATURE_LOW)) is not None:
-        template_ = await cg.templatable(target_temp_low, args, cg.float_)
-        cg.add(var.set_target_temperature_low(template_))
-    if (target_temp_high := config.get(CONF_TARGET_TEMPERATURE_HIGH)) is not None:
-        template_ = await cg.templatable(target_temp_high, args, cg.float_)
-        cg.add(var.set_target_temperature_high(template_))
-    if (target_humidity := config.get(CONF_TARGET_HUMIDITY)) is not None:
-        template_ = await cg.templatable(target_humidity, args, cg.float_)
-        cg.add(var.set_target_humidity(template_))
-    if (fan_mode := config.get(CONF_FAN_MODE)) is not None:
-        template_ = await cg.templatable(fan_mode, args, ClimateFanMode)
-        cg.add(var.set_fan_mode(template_))
-    if (custom_fan_mode := config.get(CONF_CUSTOM_FAN_MODE)) is not None:
-        template_ = await cg.templatable(custom_fan_mode, args, cg.std_string)
-        cg.add(var.set_custom_fan_mode(template_))
-    if (preset := config.get(CONF_PRESET)) is not None:
-        template_ = await cg.templatable(preset, args, ClimatePreset)
-        cg.add(var.set_preset(template_))
-    if (custom_preset := config.get(CONF_CUSTOM_PRESET)) is not None:
-        template_ = await cg.templatable(custom_preset, args, cg.std_string)
-        cg.add(var.set_custom_preset(template_))
-    if (swing_mode := config.get(CONF_SWING_MODE)) is not None:
-        template_ = await cg.templatable(swing_mode, args, ClimateSwingMode)
-        cg.add(var.set_swing_mode(template_))
-    return var
+
+    # All configured fields are folded into a single stateless lambda whose
+    # constants live in flash; the action stores only a function pointer.
+    # For custom_fan_mode/custom_preset the static-string path emits the
+    # (const char *, size_t) overload of set_fan_mode/set_preset to avoid
+    # constructing a std::string and calling runtime strlen.
+    FIELDS = (
+        (CONF_MODE, "set_mode", ClimateMode),
+        (CONF_TARGET_TEMPERATURE, "set_target_temperature", cg.float_),
+        (CONF_TARGET_TEMPERATURE_LOW, "set_target_temperature_low", cg.float_),
+        (CONF_TARGET_TEMPERATURE_HIGH, "set_target_temperature_high", cg.float_),
+        (CONF_TARGET_HUMIDITY, "set_target_humidity", cg.float_),
+        (CONF_FAN_MODE, "set_fan_mode", ClimateFanMode),
+        (CONF_CUSTOM_FAN_MODE, "set_fan_mode", cg.std_string),
+        (CONF_PRESET, "set_preset", ClimatePreset),
+        (CONF_CUSTOM_PRESET, "set_preset", cg.std_string),
+        (CONF_SWING_MODE, "set_swing_mode", ClimateSwingMode),
+    )
+
+    # Normalize trigger args to `const std::remove_cvref_t<T> &` so the
+    # apply lambda and any inner field lambdas (generated below via
+    # `process_lambda`) share one parameter spelling that's well-formed for
+    # any T (value, ref, or const-ref). Matches ControlAction::ApplyFn.
+    normalized_args = [
+        (cg.RawExpression(f"const std::remove_cvref_t<{cg.safe_exp(t)}> &"), n)
+        for t, n in args
+    ]
+
+    fwd_args = ", ".join(name for _, name in args)
+    body_lines: list[str] = []
+
+    for conf_key, setter, type_ in FIELDS:
+        if (value := config.get(conf_key)) is None:
+            continue
+        if isinstance(value, Lambda):
+            inner = await cg.process_lambda(value, normalized_args, return_type=type_)
+            body_lines.append(f"call.{setter}(({inner})({fwd_args}));")
+        elif type_ is cg.std_string:
+            # Static custom strings: emit a flash literal and pass the
+            # UTF-8 byte length to skip the runtime strlen inside
+            # set_fan_mode/set_preset.
+            literal = cg.safe_exp(value)
+            body_lines.append(
+                f"call.{setter}({literal}, {len(value.encode('utf-8'))});"
+            )
+        else:
+            body_lines.append(f"call.{setter}({cg.safe_exp(value)});")
+
+    apply_args = [
+        (ClimateCall.operator("ref"), "call"),
+        *normalized_args,
+    ]
+    apply_lambda = LambdaExpression(
+        ["\n".join(body_lines)],
+        apply_args,
+        capture="",
+        return_type=cg.void,
+    )
+    return cg.new_Pvariable(action_id, template_arg, paren, apply_lambda)
 
 
 @coroutine_with_priority(CoroPriority.CORE)
diff --git a/esphome/components/climate/automation.h b/esphome/components/climate/automation.h
index fac56d9d9e..6ac9bd8bae 100644
--- a/esphome/components/climate/automation.h
+++ b/esphome/components/climate/automation.h
@@ -5,42 +5,32 @@
 
 namespace esphome::climate {
 
+// All configured fields are baked into a single stateless lambda whose
+// constants live in flash. The action only stores one function pointer
+// plus one parent pointer, regardless of how many fields the user set.
+// Trigger args are forwarded to the apply function so user lambdas
+// (e.g. `target_temperature: !lambda "return x;"`) keep working.
+//
+// Trigger args are normalized to `const std::remove_cvref_t<Ts> &...` so
+// the codegen can emit a matching parameter list for both the apply lambda
+// and any inner field lambdas without producing invalid C++ source text
+// (e.g. `const T & &` if Ts already carries a reference, or `const const
+// T &` if Ts already carries a const). This keeps trigger args no-copy
+// regardless of whether the trigger supplies `T`, `T &`, or `const T &`.
 template<typename... Ts> class ControlAction : public Action<Ts...> {
  public:
-  explicit ControlAction(Climate *climate) : climate_(climate) {}
-
-  TEMPLATABLE_VALUE(ClimateMode, mode)
-  TEMPLATABLE_VALUE(float, target_temperature)
-  TEMPLATABLE_VALUE(float, target_temperature_low)
-  TEMPLATABLE_VALUE(float, target_temperature_high)
-  TEMPLATABLE_VALUE(float, target_humidity)
-  TEMPLATABLE_VALUE(bool, away)
-  TEMPLATABLE_VALUE(ClimateFanMode, fan_mode)
-  TEMPLATABLE_VALUE(std::string, custom_fan_mode)
-  TEMPLATABLE_VALUE(ClimatePreset, preset)
-  TEMPLATABLE_VALUE(std::string, custom_preset)
-  TEMPLATABLE_VALUE(ClimateSwingMode, swing_mode)
+  using ApplyFn = void (*)(ClimateCall &, const std::remove_cvref_t<Ts> &...);
+  ControlAction(Climate *climate, ApplyFn apply) : climate_(climate), apply_(apply) {}
 
   void play(const Ts &...x) override {
     auto call = this->climate_->make_call();
-    call.set_mode(this->mode_.optional_value(x...));
-    call.set_target_temperature(this->target_temperature_.optional_value(x...));
-    call.set_target_temperature_low(this->target_temperature_low_.optional_value(x...));
-    call.set_target_temperature_high(this->target_temperature_high_.optional_value(x...));
-    call.set_target_humidity(this->target_humidity_.optional_value(x...));
-    if (away_.has_value()) {
-      call.set_preset(away_.value(x...) ? CLIMATE_PRESET_AWAY : CLIMATE_PRESET_HOME);
-    }
-    call.set_fan_mode(this->fan_mode_.optional_value(x...));
-    call.set_fan_mode(this->custom_fan_mode_.optional_value(x...));
-    call.set_preset(this->preset_.optional_value(x...));
-    call.set_preset(this->custom_preset_.optional_value(x...));
-    call.set_swing_mode(this->swing_mode_.optional_value(x...));
+    this->apply_(call, x...);
     call.perform();
   }
 
  protected:
   Climate *climate_;
+  ApplyFn apply_;
 };
 
 class ControlTrigger : public Trigger<ClimateCall &> {
diff --git a/esphome/components/climate/climate.cpp b/esphome/components/climate/climate.cpp
index e132497140..b41ca4a540 100644
--- a/esphome/components/climate/climate.cpp
+++ b/esphome/components/climate/climate.cpp
@@ -374,7 +374,8 @@ void Climate::save_state_(const ClimateTraits &traits) {
 #define TEMP_IGNORE_MEMACCESS
 #endif
   ClimateDeviceRestoreState state{};
-  // initialize as zero to prevent random data on stack triggering erase
+  // initialize as zero (including padding) to prevent random data on stack triggering erase
+  // NOLINTNEXTLINE(bugprone-raw-memory-call-on-non-trivial-type) -- intentional bytewise zero for RTC save
   memset(&state, 0, sizeof(ClimateDeviceRestoreState));
 #ifdef TEMP_IGNORE_MEMACCESS
 #pragma GCC diagnostic pop
diff --git a/esphome/components/cover/__init__.py b/esphome/components/cover/__init__.py
index 41efd2ba7a..954ad7a345 100644
--- a/esphome/components/cover/__init__.py
+++ b/esphome/components/cover/__init__.py
@@ -1,3 +1,5 @@
+from collections.abc import Callable
+from dataclasses import dataclass
 import logging
 
 from esphome import automation
@@ -36,14 +38,14 @@ from esphome.const import (
     DEVICE_CLASS_SHUTTER,
     DEVICE_CLASS_WINDOW,
 )
-from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, ID, CoroPriority, Lambda, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
     queue_entity_register,
     setup_device_class,
     setup_entity,
 )
-from esphome.cpp_generator import MockObj, MockObjClass
+from esphome.cpp_generator import LambdaExpression, MockObj, MockObjClass
 from esphome.types import ConfigType, TemplateArgsType
 
 IS_PLATFORM_COMPONENT = True
@@ -68,6 +70,7 @@ _LOGGER = logging.getLogger(__name__)
 cover_ns = cg.esphome_ns.namespace("cover")
 
 Cover = cover_ns.class_("Cover", cg.EntityBase)
+CoverCall = cover_ns.class_("CoverCall")
 
 COVER_OPEN = cover_ns.COVER_OPEN
 COVER_CLOSED = cover_ns.COVER_CLOSED
@@ -294,25 +297,94 @@ COVER_CONTROL_ACTION_SCHEMA = cv.Schema(
 )
 
 
+@dataclass(frozen=True)
+class ApplyField:
+    """One field in a folded-lambda action.
+
+    `conf_key` is the YAML key looked up in `config`. When present, the
+    helper emits `statement_fn(target, value_expr)` into the lambda body.
+    `target` is whatever the statement function needs to identify the
+    field (typically a setter name like `"set_position"` or a struct
+    member like `"position"`). `type_` is the C++ return type for
+    `cg.process_lambda` when the value is a user lambda.
+    """
+
+    conf_key: str
+    target: str
+    type_: object
+
+
+async def build_apply_lambda_action(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+    fields: tuple[ApplyField, ...],
+    prefix_args: list[tuple[object, str]],
+    statement_fn: Callable[[str, str], str],
+) -> MockObj:
+    """Fold configured fields into a single stateless apply lambda action.
+
+    Used by both `cover.control` and `cover.template.publish` (and shared
+    with the template/cover platform). Constants are emitted as flash
+    immediates; user lambdas are invoked inline so trigger args still flow.
+    The trigger arg types are wrapped as `const T &` to match the
+    `void (*)(..., const Ts &...)` ApplyFn signature.
+    """
+    paren = await cg.get_variable(config[CONF_ID])
+    fwd_args = ", ".join(name for _, name in args)
+    body_lines: list[str] = []
+    for field in fields:
+        if (value := config.get(field.conf_key)) is None:
+            continue
+        if isinstance(value, Lambda):
+            inner = await cg.process_lambda(value, args, return_type=field.type_)
+            value_expr = f"({inner})({fwd_args})"
+        else:
+            value_expr = str(cg.safe_exp(value))
+        body_lines.append(statement_fn(field.target, value_expr))
+
+    apply_args = [
+        *prefix_args,
+        *((t.operator("const").operator("ref"), n) for t, n in args),
+    ]
+    apply_lambda = LambdaExpression(
+        ["\n".join(body_lines)],
+        apply_args,
+        capture="",
+        return_type=cg.void,
+    )
+    return cg.new_Pvariable(action_id, template_arg, paren, apply_lambda)
+
+
+# CONF_STATE and CONF_POSITION are cv.Exclusive in the schema, so at most
+# one is present and both dispatch to set_position.
+_COVER_CONTROL_FIELDS: tuple[ApplyField, ...] = (
+    ApplyField(CONF_STOP, "set_stop", cg.bool_),
+    ApplyField(CONF_STATE, "set_position", cg.float_),
+    ApplyField(CONF_POSITION, "set_position", cg.float_),
+    ApplyField(CONF_TILT, "set_tilt", cg.float_),
+)
+
+
 @automation.register_action(
     "cover.control", ControlAction, COVER_CONTROL_ACTION_SCHEMA, synchronous=True
 )
-async def cover_control_to_code(config, action_id, template_arg, args):
-    paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if (stop := config.get(CONF_STOP)) is not None:
-        template_ = await cg.templatable(stop, args, cg.bool_)
-        cg.add(var.set_stop(template_))
-    if (state := config.get(CONF_STATE)) is not None:
-        template_ = await cg.templatable(state, args, cg.float_)
-        cg.add(var.set_position(template_))
-    if (position := config.get(CONF_POSITION)) is not None:
-        template_ = await cg.templatable(position, args, cg.float_)
-        cg.add(var.set_position(template_))
-    if (tilt := config.get(CONF_TILT)) is not None:
-        template_ = await cg.templatable(tilt, args, cg.float_)
-        cg.add(var.set_tilt(template_))
-    return var
+async def cover_control_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
+    return await build_apply_lambda_action(
+        config=config,
+        action_id=action_id,
+        template_arg=template_arg,
+        args=args,
+        fields=_COVER_CONTROL_FIELDS,
+        prefix_args=[(CoverCall.operator("ref"), "call")],
+        statement_fn=lambda setter, expr: f"call.{setter}({expr});",
+    )
 
 
 COVER_CONDITION_SCHEMA = cv.maybe_simple_value(
diff --git a/esphome/components/cover/automation.h b/esphome/components/cover/automation.h
index f121e5c2d6..e2384c2359 100644
--- a/esphome/components/cover/automation.h
+++ b/esphome/components/cover/automation.h
@@ -46,48 +46,41 @@ template<typename... Ts> class ToggleAction : public Action<Ts...> {
   Cover *cover_;
 };
 
+// All configured fields are baked into a single stateless lambda whose
+// constants live in flash. Each action stores only one function pointer
+// plus one parent pointer, regardless of how many fields the user set.
+// Trigger args are forwarded to the apply function so user lambdas
+// (e.g. `position: !lambda "return x;"`) keep working.
+
 template<typename... Ts> class ControlAction : public Action<Ts...> {
  public:
-  explicit ControlAction(Cover *cover) : cover_(cover) {}
-
-  TEMPLATABLE_VALUE(bool, stop)
-  TEMPLATABLE_VALUE(float, position)
-  TEMPLATABLE_VALUE(float, tilt)
+  using ApplyFn = void (*)(CoverCall &, const Ts &...);
+  ControlAction(Cover *cover, ApplyFn apply) : cover_(cover), apply_(apply) {}
 
   void play(const Ts &...x) override {
     auto call = this->cover_->make_call();
-    if (this->stop_.has_value())
-      call.set_stop(this->stop_.value(x...));
-    if (this->position_.has_value())
-      call.set_position(this->position_.value(x...));
-    if (this->tilt_.has_value())
-      call.set_tilt(this->tilt_.value(x...));
+    this->apply_(call, x...);
     call.perform();
   }
 
  protected:
   Cover *cover_;
+  ApplyFn apply_;
 };
 
 template<typename... Ts> class CoverPublishAction : public Action<Ts...> {
  public:
-  CoverPublishAction(Cover *cover) : cover_(cover) {}
-  TEMPLATABLE_VALUE(float, position)
-  TEMPLATABLE_VALUE(float, tilt)
-  TEMPLATABLE_VALUE(CoverOperation, current_operation)
+  using ApplyFn = void (*)(Cover *, const Ts &...);
+  CoverPublishAction(Cover *cover, ApplyFn apply) : cover_(cover), apply_(apply) {}
 
   void play(const Ts &...x) override {
-    if (this->position_.has_value())
-      this->cover_->position = this->position_.value(x...);
-    if (this->tilt_.has_value())
-      this->cover_->tilt = this->tilt_.value(x...);
-    if (this->current_operation_.has_value())
-      this->cover_->current_operation = this->current_operation_.value(x...);
+    this->apply_(this->cover_, x...);
     this->cover_->publish_state();
   }
 
  protected:
   Cover *cover_;
+  ApplyFn apply_;
 };
 
 template<bool OPEN, typename... Ts> class CoverPositionCondition : public Condition<Ts...> {
diff --git a/esphome/components/dashboard_import/__init__.py b/esphome/components/dashboard_import/__init__.py
index dbe5532902..30b3394165 100644
--- a/esphome/components/dashboard_import/__init__.py
+++ b/esphome/components/dashboard_import/__init__.py
@@ -89,6 +89,17 @@ def import_config(
     network: str = CONF_WIFI,
     encryption: bool = False,
 ) -> None:
+    """Materialise a dashboard-imported device's YAML on disk.
+
+    Used by:
+    - esphome.dashboard (legacy dashboard)
+    - device-builder (esphome/device-builder) — called from the
+      ``devices/import`` WS handler to seed the YAML for an adopted
+      factory firmware. Coordinate before changing the kwargs or the
+      generated YAML's top-level keys; both consumers depend on the
+      output shape (``esphome.name`` / ``packages:`` import url) to
+      route subsequent compile + flash operations.
+    """
     p = Path(path)
 
     if p.exists():
diff --git a/esphome/components/debug/debug_zephyr.cpp b/esphome/components/debug/debug_zephyr.cpp
index 49790b5b9a..81c8612784 100644
--- a/esphome/components/debug/debug_zephyr.cpp
+++ b/esphome/components/debug/debug_zephyr.cpp
@@ -17,11 +17,13 @@ constexpr std::uintptr_t MBR_PARAM_PAGE_ADDR = 0xFFC;
 constexpr std::uintptr_t MBR_BOOTLOADER_ADDR = 0xFF8;
 
 static inline uint32_t read_mem_u32(uintptr_t addr) {
-  return *reinterpret_cast<volatile uint32_t *>(addr);  // NOLINT(performance-no-int-to-ptr)
+  // NOLINTNEXTLINE(performance-no-int-to-ptr,clang-analyzer-core.FixedAddressDereference)
+  return *reinterpret_cast<volatile uint32_t *>(addr);
 }
 
 static inline uint8_t read_mem_u8(uintptr_t addr) {
-  return *reinterpret_cast<volatile uint8_t *>(addr);  // NOLINT(performance-no-int-to-ptr)
+  // NOLINTNEXTLINE(performance-no-int-to-ptr,clang-analyzer-core.FixedAddressDereference)
+  return *reinterpret_cast<volatile uint8_t *>(addr);
 }
 
 // defines from https://github.com/adafruit/Adafruit_nRF52_Bootloader which prints those information
@@ -98,6 +100,7 @@ void DebugComponent::log_partition_info_() {
 #define NRF_PERIPH_ENABLED(periph, reg) \
   YESNO(((reg)->ENABLE & periph##_ENABLE_ENABLE_Msk) == (periph##_ENABLE_ENABLE_Enabled << periph##_ENABLE_ENABLE_Pos))
 
+// NOLINTBEGIN(clang-analyzer-core.FixedAddressDereference) -- nRF peripheral registers are MMIO at fixed addresses
 static void log_peripherals_info() {
   // most peripherals are enabled only when in use so ESP_LOGV is enough
   ESP_LOGV(TAG, "Peripherals status:");
@@ -131,6 +134,7 @@ static void log_peripherals_info() {
            YESNO((NRF_CRYPTOCELL->ENABLE & CRYPTOCELL_ENABLE_ENABLE_Msk) ==
                  (CRYPTOCELL_ENABLE_ENABLE_Enabled << CRYPTOCELL_ENABLE_ENABLE_Pos)));
 }
+// NOLINTEND(clang-analyzer-core.FixedAddressDereference)
 #undef NRF_PERIPH_ENABLED
 #endif
 
@@ -159,8 +163,9 @@ size_t DebugComponent::get_device_info_(std::span<char, DEVICE_INFO_BUFFER_SIZE>
   char *buf = buffer.data();
 
   // Main supply status
-  const char *supply_status =
-      (nrf_power_mainregstatus_get(NRF_POWER) == NRF_POWER_MAINREGSTATUS_NORMAL) ? "Normal voltage." : "High voltage.";
+  // NOLINTNEXTLINE(clang-analyzer-core.FixedAddressDereference) -- NRF_POWER is MMIO at a fixed address
+  auto regstatus = nrf_power_mainregstatus_get(NRF_POWER);
+  const char *supply_status = (regstatus == NRF_POWER_MAINREGSTATUS_NORMAL) ? "Normal voltage." : "High voltage.";
   ESP_LOGD(TAG, "Main supply status: %s", supply_status);
   pos = buf_append_str(buf, size, pos, "|Main supply status: ");
   pos = buf_append_str(buf, size, pos, supply_status);
diff --git a/esphome/components/deep_sleep/__init__.py b/esphome/components/deep_sleep/__init__.py
index 0ca557bd6d..9666c8e507 100644
--- a/esphome/components/deep_sleep/__init__.py
+++ b/esphome/components/deep_sleep/__init__.py
@@ -193,11 +193,14 @@ def _validate_ex1_wakeup_mode(value):
 
 
 def _validate_sleep_duration(value: core.TimePeriod) -> core.TimePeriod:
-    if not CORE.is_bk72xx:
-        return value
-    max_duration = core.TimePeriod(hours=36)
-    if value > max_duration:
-        raise cv.Invalid("sleep duration cannot be more than 36 hours on BK72XX")
+    if CORE.is_bk72xx:
+        max_duration = core.TimePeriod(hours=36)
+        if value > max_duration:
+            raise cv.Invalid("sleep duration cannot be more than 36 hours on BK72XX")
+    elif CORE.using_zephyr:
+        max_duration = core.TimePeriod(days=49)
+        if value > max_duration:
+            raise cv.Invalid("sleep duration cannot be more than 49 days on Zephyr")
     return value
 
 
diff --git a/esphome/components/deep_sleep/deep_sleep_component.cpp b/esphome/components/deep_sleep/deep_sleep_component.cpp
index d2c5db54b3..d5e34b1f1c 100644
--- a/esphome/components/deep_sleep/deep_sleep_component.cpp
+++ b/esphome/components/deep_sleep/deep_sleep_component.cpp
@@ -9,18 +9,11 @@ static const char *const TAG = "deep_sleep";
 // 5 seconds for deep sleep to ensure clean disconnect from Home Assistant
 static const uint32_t TEARDOWN_TIMEOUT_DEEP_SLEEP_MS = 5000;
 
-bool global_has_deep_sleep = false;                   // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
-std::atomic<DeepSleepComponent *> global_deep_sleep;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+bool global_has_deep_sleep = false;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
 void DeepSleepComponent::setup() {
-#ifdef USE_ZEPHYR
-  k_sem_init(&this->wakeup_sem_, 0, 1);
-#endif
   global_has_deep_sleep = true;
   this->schedule_sleep_();
-  // It can be used from another thread for waking up the device.
-  // It should be called as last item in setup.
-  global_deep_sleep.store(this);
 }
 
 void DeepSleepComponent::schedule_sleep_() {
diff --git a/esphome/components/deep_sleep/deep_sleep_component.h b/esphome/components/deep_sleep/deep_sleep_component.h
index 854ab152a1..59381eeabe 100644
--- a/esphome/components/deep_sleep/deep_sleep_component.h
+++ b/esphome/components/deep_sleep/deep_sleep_component.h
@@ -4,8 +4,6 @@
 #include "esphome/core/component.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
-#include <atomic>
-
 #ifdef USE_ESP32
 #include <esp_sleep.h>
 #endif
@@ -15,10 +13,6 @@
 #include "esphome/core/time.h"
 #endif
 
-#ifdef USE_ZEPHYR
-#include <zephyr/kernel.h>
-#endif
-
 #include <cinttypes>
 
 namespace esphome {
@@ -125,9 +119,6 @@ class DeepSleepComponent : public Component {
 
   void prevent_deep_sleep();
   void allow_deep_sleep();
-#ifdef USE_ZEPHYR
-  void wakeup();
-#endif
 
  protected:
   // Returns nullopt if no run duration is set. Otherwise, returns the run
@@ -167,9 +158,6 @@ class DeepSleepComponent : public Component {
   optional<uint32_t> run_duration_;
   bool next_enter_deep_sleep_{false};
   bool prevent_{false};
-#ifdef USE_ZEPHYR
-  k_sem wakeup_sem_;
-#endif
 };
 
 extern bool global_has_deep_sleep;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
@@ -256,8 +244,5 @@ template<typename... Ts> class AllowDeepSleepAction : public Action<Ts...>, publ
   void play(const Ts &...x) override { this->parent_->allow_deep_sleep(); }
 };
 
-extern std::atomic<DeepSleepComponent *>
-    global_deep_sleep;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
-
 }  // namespace deep_sleep
 }  // namespace esphome
diff --git a/esphome/components/deep_sleep/deep_sleep_zephyr.cpp b/esphome/components/deep_sleep/deep_sleep_zephyr.cpp
index 82d6d8c7de..f77b73cd58 100644
--- a/esphome/components/deep_sleep/deep_sleep_zephyr.cpp
+++ b/esphome/components/deep_sleep/deep_sleep_zephyr.cpp
@@ -1,17 +1,13 @@
 #include "deep_sleep_component.h"
 #ifdef USE_ZEPHYR
 #include "esphome/core/log.h"
+#include "esphome/core/wake.h"
 #include <zephyr/sys/poweroff.h>
-#include <zephyr/kernel.h>
-#include <zephyr/stats/stats.h>
-#include <zephyr/pm/pm.h>
 
 namespace esphome::deep_sleep {
 
 static const char *const TAG = "deep_sleep";
 
-void DeepSleepComponent::wakeup() { k_sem_give(&this->wakeup_sem_); }
-
 optional<uint32_t> DeepSleepComponent::get_run_duration_() const { return this->run_duration_; }
 
 void DeepSleepComponent::dump_config_platform_() {}
@@ -19,9 +15,8 @@ void DeepSleepComponent::dump_config_platform_() {}
 bool DeepSleepComponent::prepare_to_sleep_() { return true; }
 
 void DeepSleepComponent::deep_sleep_() {
-  k_timeout_t sleep_duration = K_FOREVER;
   if (this->sleep_duration_.has_value()) {
-    sleep_duration = K_USEC(*this->sleep_duration_);
+    esphome::internal::wakeable_delay(static_cast<uint32_t>(*this->sleep_duration_ / 1000));
   } else {
 #ifndef USE_ZIGBEE
     // the device can be woken up through one of the following signals:
@@ -33,11 +28,12 @@ void DeepSleepComponent::deep_sleep_() {
     //
     // The system is reset when it wakes up from System OFF mode.
     sys_poweroff();
+#else
+    esphome::internal::wakeable_delay(UINT32_MAX);
 #endif
   }
-  // It might wake up immediately if k_sem_give was called again after wake up
-  int ret = k_sem_take(&this->wakeup_sem_, sleep_duration);
-  if (ret == 0) {
+  const bool woke = esphome::wake_request_take();
+  if (woke) {
     ESP_LOGD(TAG, "Woken up by another thread");
   } else {
     ESP_LOGD(TAG, "Timeout expired (normal sleep)");
diff --git a/esphome/components/demo/demo_alarm_control_panel.h b/esphome/components/demo/demo_alarm_control_panel.h
index 9976e5c7f0..5f0725dd4b 100644
--- a/esphome/components/demo/demo_alarm_control_panel.h
+++ b/esphome/components/demo/demo_alarm_control_panel.h
@@ -29,7 +29,7 @@ class DemoAlarmControlPanel : public AlarmControlPanel, public Component {
  protected:
   void control(const AlarmControlPanelCall &call) override {
     auto state = call.get_state().value_or(ACP_STATE_DISARMED);
-    auto code = call.get_code();
+    const auto &code = call.get_code();
     switch (state) {
       case ACP_STATE_ARMED_AWAY:
         if (this->get_requires_code_to_arm()) {
diff --git a/esphome/components/dfrobot_sen0395/dfrobot_sen0395.cpp b/esphome/components/dfrobot_sen0395/dfrobot_sen0395.cpp
index f47025698b..98901bd353 100644
--- a/esphome/components/dfrobot_sen0395/dfrobot_sen0395.cpp
+++ b/esphome/components/dfrobot_sen0395/dfrobot_sen0395.cpp
@@ -104,8 +104,9 @@ int8_t CircularCommandQueue::enqueue(std::unique_ptr<Command> cmd) {
   if (this->is_full()) {
     ESP_LOGE(TAG, "Command queue is full");
     return -1;
-  } else if (this->is_empty())
+  } else if (this->is_empty()) {
     front_++;
+  }
   rear_ = (rear_ + 1) % COMMAND_QUEUE_SIZE;
   commands_[rear_] = std::move(cmd);  // Transfer ownership using std::move
   return 1;
diff --git a/esphome/components/e131/e131_addressable_light_effect.cpp b/esphome/components/e131/e131_addressable_light_effect.cpp
index f6010a7cc9..f6300874ac 100644
--- a/esphome/components/e131/e131_addressable_light_effect.cpp
+++ b/esphome/components/e131/e131_addressable_light_effect.cpp
@@ -56,8 +56,7 @@ bool E131AddressableLightEffect::process_(int universe, const E131Packet &packet
   // limit amount of lights per universe and received
   // packet.count is the number of DMX bytes including start code; divide by channels to get the number of lights
   int lights_in_packet = (packet.count > 0) ? (packet.count - 1) / channels_ : 0;
-  int output_end =
-      std::min(it->size(), std::min(output_offset + get_lights_per_universe(), output_offset + lights_in_packet));
+  int output_end = std::min({it->size(), output_offset + get_lights_per_universe(), output_offset + lights_in_packet});
   auto *input_data = packet.values + 1;
 
   auto effect_name = get_name();
diff --git a/esphome/components/ens160_base/ens160_base.cpp b/esphome/components/ens160_base/ens160_base.cpp
index e1cee5005c..42baa68b35 100644
--- a/esphome/components/ens160_base/ens160_base.cpp
+++ b/esphome/components/ens160_base/ens160_base.cpp
@@ -5,6 +5,15 @@
 // Implementation based on:
 //   https://github.com/sciosense/ENS160_driver
 
+// For best performance, the sensor shall be operated in normal indoor air in the range -5 to 60°C
+// (typical: 25°C); relative humidity: 20 to 80%RH (typical: 50%RH), non-condensing with no aggressive
+// or poisonous gases present. Prolonged exposure to environments outside these conditions can affect
+// performance and lifetime of the sensor.
+// The sensor is designed for indoor use and is not waterproof or dustproof. It should be protected from
+// water, condensation, dust, and aggressive gases. Note that the status will only be stored in non-volatile
+// memory after an initial 24 h of continuous operation. If unpowered before the conclusion of that period,
+// the ENS160 will resume "Initial Start-up" mode after re-powering.
+
 #include "ens160_base.h"
 #include "esphome/core/log.h"
 #include "esphome/core/hal.h"
@@ -14,7 +23,9 @@ namespace ens160_base {
 
 static const char *const TAG = "ens160";
 
-static const uint8_t ENS160_BOOTING = 10;
+// Datasheet specifies 10ms, but some users report that 10ms is not sufficient for the
+// sensor to boot and be ready for commands. 11ms seems to be a safe value.
+static const uint8_t ENS160_BOOTING = 11;
 
 static const uint16_t ENS160_PART_ID = 0x0160;
 
@@ -91,6 +102,8 @@ void ENS160Component::setup() {
     this->mark_failed();
     return;
   }
+  delay(ENS160_BOOTING);
+
   // clear command
   if (!this->write_byte(ENS160_REG_COMMAND, ENS160_COMMAND_NOP)) {
     this->error_code_ = WRITE_FAILED;
@@ -102,6 +115,7 @@ void ENS160Component::setup() {
     this->mark_failed();
     return;
   }
+  delay(ENS160_BOOTING);
 
   // read firmware version
   if (!this->write_byte(ENS160_REG_COMMAND, ENS160_COMMAND_GET_APPVER)) {
@@ -109,6 +123,8 @@ void ENS160Component::setup() {
     this->mark_failed();
     return;
   }
+  delay(ENS160_BOOTING);
+
   uint8_t version_data[3];
   if (!this->read_bytes(ENS160_REG_GPR_READ_4, version_data, 3)) {
     this->error_code_ = READ_FAILED;
@@ -223,7 +239,6 @@ void ENS160Component::update() {
   if (this->aqi_ != nullptr) {
     // remove reserved bits, just in case they are used in future
     data_aqi = ENS160_DATA_AQI & data_aqi;
-
     this->aqi_->publish_state(data_aqi);
   }
 
diff --git a/esphome/components/esp32/__init__.py b/esphome/components/esp32/__init__.py
index 78a1715ccf..b60dab3634 100644
--- a/esphome/components/esp32/__init__.py
+++ b/esphome/components/esp32/__init__.py
@@ -489,6 +489,18 @@ def get_board(core_obj=None):
 
 
 def get_download_types(storage_json):
+    """Binary-download entries for a built ESP32 firmware.
+
+    Used by:
+    - esphome.dashboard (legacy "Download .bin" button)
+    - device-builder (esphome/device-builder) — same dispatch via
+      ``importlib.import_module(f"esphome.components.{platform}")``
+      then ``module.get_download_types(storage)``. The contract is
+      "returns ``list[dict]`` with at least ``title`` /
+      ``description`` / ``file`` / ``download`` keys"; please keep
+      the shape stable so the new dashboard's download panel
+      doesn't have to special-case per-platform schemas.
+    """
     return [
         {
             "title": "Factory format (Previously Modern)",
@@ -729,6 +741,9 @@ ESP_IDF_FRAMEWORK_VERSION_LOOKUP = {
     "dev": cv.Version(5, 5, 4),
 }
 ESP_IDF_PLATFORM_VERSION_LOOKUP = {
+    cv.Version(
+        6, 0, 1
+    ): "https://github.com/pioarduino/platform-espressif32.git#prep_IDF6",
     cv.Version(
         6, 0, 0
     ): "https://github.com/pioarduino/platform-espressif32.git#prep_IDF6",
@@ -1724,15 +1739,16 @@ async def to_code(config):
         CORE.relative_internal_path(".espressif")
     )
 
+    # Both ESP-IDF and ESP32 Arduino builds generate IDF app metadata. Keep
+    # volatile build path/time data out of the binary so equivalent projects can
+    # produce reproducible outputs and downstream tooling can reuse artifacts.
+    add_idf_sdkconfig_option("CONFIG_APP_REPRODUCIBLE_BUILD", True)
+
     if conf[CONF_TYPE] == FRAMEWORK_ESP_IDF:
         cg.add_build_flag("-DUSE_ESP_IDF")
         cg.add_build_flag("-DUSE_ESP32_FRAMEWORK_ESP_IDF")
         if use_platformio:
             cg.add_platformio_option("framework", "espidf")
-            # Strip volatile build path/time metadata from PlatformIO-managed
-            # ESP-IDF builds so equivalent projects can produce reproducible
-            # outputs and downstream tooling can safely reuse artifacts.
-            add_idf_sdkconfig_option("CONFIG_APP_REPRODUCIBLE_BUILD", True)
 
         # Wrap std::__throw_* functions to abort immediately, eliminating ~3KB of
         # exception class overhead. See throw_stubs.cpp for implementation.
@@ -1749,7 +1765,17 @@ async def to_code(config):
 
         # Wrap FILE*-based printf functions to eliminate newlib's _vfprintf_r
         # (~11 KB). See printf_stubs.cpp for implementation.
-        if conf[CONF_ADVANCED][CONF_ENABLE_FULL_PRINTF]:
+        #
+        # The wrap is only beneficial against newlib. Picolibc's tinystdio
+        # implements vsnprintf by building a string-output FILE and calling
+        # vfprintf, so vfprintf is unconditionally linked in by any caller
+        # of snprintf/vsnprintf — effectively every build — and the wrap
+        # saves nothing while costing ~170 B of shim. IDF 5.x defaults to
+        # newlib on every variant; IDF 6.0+ switches to picolibc on every
+        # variant.
+        if conf[CONF_ADVANCED][CONF_ENABLE_FULL_PRINTF] or idf_version() >= cv.Version(
+            6, 0, 0
+        ):
             cg.add_define("USE_FULL_PRINTF")
         else:
             for symbol in ("vprintf", "printf", "fprintf", "vfprintf"):
diff --git a/esphome/components/esp32/core.cpp b/esphome/components/esp32/core.cpp
index 1c63137183..5249f4a59e 100644
--- a/esphome/components/esp32/core.cpp
+++ b/esphome/components/esp32/core.cpp
@@ -1,17 +1,8 @@
 #ifdef USE_ESP32
 
-#include "esphome/core/defines.h"
-#include "crash_handler.h"
 #include "esphome/core/application.h"
-#include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
+#include "esphome/core/defines.h"
 #include "preferences.h"
-#include <esp_clk_tree.h>
-#include <esp_cpu.h>
-#include <esp_idf_version.h>
-#include <esp_ota_ops.h>
-#include <esp_task_wdt.h>
-#include <esp_timer.h>
 #include <freertos/FreeRTOS.h>
 #include <freertos/task.h>
 
@@ -22,63 +13,7 @@ extern "C" __attribute__((weak)) void initArduino() {}
 
 namespace esphome {
 
-void HOT yield() { vPortYield(); }
-// Use xTaskGetTickCount() when tick rate is 1 kHz (ESPHome's default via sdkconfig),
-// falling back to esp_timer for non-standard rates. IRAM_ATTR is required because
-// Wiegand and ZyAura call millis() from IRAM_ATTR ISR handlers on ESP32.
-// xTaskGetTickCountFromISR() is used in ISR context to satisfy the FreeRTOS API contract.
-uint32_t IRAM_ATTR HOT millis() {
-#if CONFIG_FREERTOS_HZ == 1000
-  if (xPortInIsrContext()) [[unlikely]] {
-    return xTaskGetTickCountFromISR();
-  }
-  return xTaskGetTickCount();
-#else
-  return micros_to_millis(static_cast<uint64_t>(esp_timer_get_time()));
-#endif
-}
-// millis_64() stays on esp_timer — a different clock from xTaskGetTickCount(). This is
-// safe because the two are never cross-compared: millis() values are only used for
-// millis()-vs-millis() deltas (feed_wdt, warn_blocking, component start time), while
-// millis_64() is used by the Scheduler and uptime sensors. On ESP32 (USE_NATIVE_64BIT_TIME),
-// Scheduler::millis_64_from_(now) discards the 32-bit now and calls millis_64() directly,
-// so the Scheduler is internally consistent on the esp_timer clock.
-uint64_t HOT millis_64() { return micros_to_millis<uint64_t>(static_cast<uint64_t>(esp_timer_get_time())); }
-void HOT delay(uint32_t ms) { vTaskDelay(ms / portTICK_PERIOD_MS); }
-uint32_t IRAM_ATTR HOT micros() { return (uint32_t) esp_timer_get_time(); }
-void IRAM_ATTR HOT delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
-void arch_restart() {
-  esp_restart();
-  // restart() doesn't always end execution
-  while (true) {  // NOLINT(clang-diagnostic-unreachable-code)
-    yield();
-  }
-}
-
-void arch_init() {
-#ifdef USE_ESP32_CRASH_HANDLER
-  // Read crash data from previous boot before anything else
-  esp32::crash_handler_read_and_clear();
-#endif
-
-  // Enable the task watchdog only on the loop task (from which we're currently running)
-  esp_task_wdt_add(nullptr);
-
-  // Handle OTA rollback: mark partition valid immediately unless USE_OTA_ROLLBACK is enabled,
-  // in which case safe_mode will mark it valid after confirming successful boot.
-#ifndef USE_OTA_ROLLBACK
-  esp_ota_mark_app_valid_cancel_rollback();
-#endif
-}
-void HOT arch_feed_wdt() { esp_task_wdt_reset(); }
-
-uint32_t arch_get_cpu_cycle_count() { return esp_cpu_get_cycle_count(); }
-uint32_t arch_get_cpu_freq_hz() {
-  uint32_t freq = 0;
-  esp_clk_tree_src_get_freq_hz(SOC_MOD_CLK_CPU, ESP_CLK_TREE_SRC_FREQ_PRECISION_CACHED, &freq);
-  return freq;
-}
-
+// HAL functions live in hal.cpp. This file keeps only the loop task setup.
 TaskHandle_t loop_task_handle = nullptr;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 static StaticTask_t loop_task_tcb;        // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 static StackType_t
diff --git a/esphome/components/esp32/hal.cpp b/esphome/components/esp32/hal.cpp
new file mode 100644
index 0000000000..f6199d557f
--- /dev/null
+++ b/esphome/components/esp32/hal.cpp
@@ -0,0 +1,71 @@
+#ifdef USE_ESP32
+
+// defines.h must come before crash_handler.h so USE_ESP32_CRASH_HANDLER is set
+// before crash_handler.h's #ifdef-guarded namespace block is parsed.
+#include "esphome/core/defines.h"
+#include "crash_handler.h"
+#include "esphome/core/hal.h"
+
+#include <esp_clk_tree.h>
+#include <esp_ota_ops.h>
+#include <esp_system.h>
+#include <esp_task_wdt.h>
+#include <esp_timer.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+
+// Empty esp32 namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// esp32 component's API.
+namespace esphome::esp32 {}  // namespace esphome::esp32
+
+namespace esphome {
+
+// Use xTaskGetTickCount() when tick rate is 1 kHz (ESPHome's default via sdkconfig),
+// falling back to esp_timer for non-standard rates. IRAM_ATTR is required because
+// Wiegand and ZyAura call millis() from IRAM_ATTR ISR handlers on ESP32.
+// xTaskGetTickCountFromISR() is used in ISR context to satisfy the FreeRTOS API contract.
+uint32_t IRAM_ATTR HOT millis() {
+#if CONFIG_FREERTOS_HZ == 1000
+  if (xPortInIsrContext()) [[unlikely]] {
+    return xTaskGetTickCountFromISR();
+  }
+  return xTaskGetTickCount();
+#else
+  return micros_to_millis(static_cast<uint64_t>(esp_timer_get_time()));
+#endif
+}
+
+void arch_restart() {
+  esp_restart();
+  // restart() doesn't always end execution
+  while (true) {  // NOLINT(clang-diagnostic-unreachable-code)
+    yield();
+  }
+}
+
+void arch_init() {
+#ifdef USE_ESP32_CRASH_HANDLER
+  // Read crash data from previous boot before anything else
+  esp32::crash_handler_read_and_clear();
+#endif
+
+  // Enable the task watchdog only on the loop task (from which we're currently running)
+  esp_task_wdt_add(nullptr);
+
+  // Handle OTA rollback: mark partition valid immediately unless USE_OTA_ROLLBACK is enabled,
+  // in which case safe_mode will mark it valid after confirming successful boot.
+#ifndef USE_OTA_ROLLBACK
+  esp_ota_mark_app_valid_cancel_rollback();
+#endif
+}
+
+uint32_t arch_get_cpu_freq_hz() {
+  uint32_t freq = 0;
+  esp_clk_tree_src_get_freq_hz(SOC_MOD_CLK_CPU, ESP_CLK_TREE_SRC_FREQ_PRECISION_CACHED, &freq);
+  return freq;
+}
+
+}  // namespace esphome
+
+#endif  // USE_ESP32
diff --git a/esphome/components/esp32/hal.h b/esphome/components/esp32/hal.h
new file mode 100644
index 0000000000..2180f07f6c
--- /dev/null
+++ b/esphome/components/esp32/hal.h
@@ -0,0 +1,52 @@
+#pragma once
+
+#ifdef USE_ESP32
+
+#include <cstdint>
+#include <esp_attr.h>
+#include <esp_cpu.h>
+#include <esp_task_wdt.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+
+#include "esphome/core/time_conversion.h"
+
+#ifndef PROGMEM
+#define PROGMEM
+#endif
+
+namespace esphome::esp32 {}
+
+namespace esphome {
+
+// Forward decl from helpers.h (esphome/core/helpers.h) — kept here so this
+// header does not need to pull the rest of helpers.h.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+void delay_microseconds_safe(uint32_t us);
+
+/// Returns true when executing inside an interrupt handler.
+__attribute__((always_inline)) inline bool in_isr_context() { return xPortInIsrContext() != 0; }
+
+// Forward decl from <esp_timer.h>.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+extern "C" int64_t esp_timer_get_time(void);
+
+__attribute__((always_inline)) inline void yield() { vPortYield(); }
+__attribute__((always_inline)) inline void delay(uint32_t ms) { vTaskDelay(ms / portTICK_PERIOD_MS); }
+__attribute__((always_inline)) inline uint32_t micros() { return static_cast<uint32_t>(esp_timer_get_time()); }
+uint32_t millis();
+__attribute__((always_inline)) inline uint64_t millis_64() {
+  return micros_to_millis<uint64_t>(static_cast<uint64_t>(esp_timer_get_time()));
+}
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
+__attribute__((always_inline)) inline void arch_feed_wdt() { esp_task_wdt_reset(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() { return esp_cpu_get_cycle_count(); }
+
+void arch_init();
+uint32_t arch_get_cpu_freq_hz();
+
+}  // namespace esphome
+
+#endif  // USE_ESP32
diff --git a/esphome/components/esp32/preferences.cpp b/esphome/components/esp32/preferences.cpp
index 925c4e7662..09835385ac 100644
--- a/esphome/components/esp32/preferences.cpp
+++ b/esphome/components/esp32/preferences.cpp
@@ -18,6 +18,12 @@ struct NVSData {
 
 static std::vector<NVSData> s_pending_save;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
+// open() runs from app_main() before the logger is initialized, so any failure
+// must be deferred until after global_logger is set. This is emitted from the
+// first make_preference() call, which runs from the generated setup() after
+// log->pre_setup() has run at EARLY_INIT priority.
+static esp_err_t s_open_err = ESP_OK;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+
 bool ESP32PreferenceBackend::save(const uint8_t *data, size_t len) {
   // try find in pending saves and update that
   for (auto &obj : s_pending_save) {
@@ -70,12 +76,14 @@ bool ESP32PreferenceBackend::load(uint8_t *data, size_t len) {
 }
 
 void ESP32Preferences::open() {
+  // Runs from app_main() before the logger is initialized; any logging here
+  // must be deferred. See s_open_err and make_preference() below.
   nvs_flash_init();
   esp_err_t err = nvs_open("esphome", NVS_READWRITE, &this->nvs_handle);
   if (err == 0)
     return;
 
-  ESP_LOGW(TAG, "nvs_open failed: %s - erasing NVS", esp_err_to_name(err));
+  s_open_err = err;
   nvs_flash_deinit();
   nvs_flash_erase();
   nvs_flash_init();
@@ -87,6 +95,14 @@ void ESP32Preferences::open() {
 }
 
 ESPPreferenceObject ESP32Preferences::make_preference(size_t length, uint32_t type) {
+  if (s_open_err != ESP_OK) {
+    if (this->nvs_handle == 0) {
+      ESP_LOGW(TAG, "nvs_open failed: %s - NVS unavailable", esp_err_to_name(s_open_err));
+    } else {
+      ESP_LOGW(TAG, "nvs_open failed: %s - erased NVS", esp_err_to_name(s_open_err));
+    }
+    s_open_err = ESP_OK;
+  }
   auto *pref = new ESP32PreferenceBackend();  // NOLINT(cppcoreguidelines-owning-memory)
   pref->nvs_handle = this->nvs_handle;
   pref->key = type;
diff --git a/esphome/components/esp32/printf_stubs.cpp b/esphome/components/esp32/printf_stubs.cpp
index 386fbbd79d..489c503942 100644
--- a/esphome/components/esp32/printf_stubs.cpp
+++ b/esphome/components/esp32/printf_stubs.cpp
@@ -1,32 +1,38 @@
 /*
- * Linker wrap stubs for FILE*-based printf functions.
+ * Linker wrap stubs for FILE*-based printf functions (newlib only).
  *
  * ESP-IDF SDK components (gpio driver, ringbuf, log_write) reference
- * fprintf(), printf(), vprintf(), and vfprintf() which pull in the full
- * printf implementation (~11 KB on newlib's _vfprintf_r, ~2.8 KB on
- * picolibc's vfprintf). This is a separate implementation from the one
- * used by snprintf/vsnprintf that handles FILE* stream I/O with buffering
- * and locking.
+ * fprintf(), printf(), vprintf(), and vfprintf(), which on newlib pull
+ * in _vfprintf_r (~11 KB) — a separate implementation from the one used
+ * by snprintf/vsnprintf that handles FILE* stream I/O with buffering.
  *
  * ESPHome replaces the ESP-IDF log handler via esp_log_set_vprintf_(),
  * so the SDK's vprintf() path is dead code at runtime. The fprintf()
  * and printf() calls in SDK components are only in debug/assert paths
  * (gpio_dump_io_configuration, ringbuf diagnostics) that are either
  * GC'd or never called. Crash backtraces and panic output are
- * unaffected — they use esp_rom_printf() which is a ROM function
- * and does not go through libc.
+ * unaffected; they use esp_rom_printf() which is a ROM function and
+ * does not go through libc.
  *
- * These stubs redirect through vsnprintf() (which uses _svfprintf_r
- * already in the binary) and fwrite(), allowing the linker to
- * dead-code eliminate _vfprintf_r.
+ * This wrap is newlib-only. On picolibc, vsnprintf is implemented as
+ * vfprintf into a string-output FILE, so vfprintf is unconditionally
+ * linked in by any caller of snprintf/vsnprintf and the wrap can never
+ * elide it — it just adds shim cost. Codegen forces USE_FULL_PRINTF
+ * on picolibc builds (IDF 6.0+ on all variants) so this file compiles
+ * to nothing there; the #error below catches a desynchronised gate.
  *
- * Saves ~11 KB of flash.
+ * Saves ~11 KB of flash on newlib.
  *
- * To disable these wraps, set enable_full_printf: true in the esp32
- * advanced config section.
+ * To disable this wrap on newlib, set enable_full_printf: true in the
+ * esp32 advanced config section.
  */
 
 #if defined(USE_ESP_IDF) && !defined(USE_FULL_PRINTF)
+
+#ifdef __PICOLIBC__
+#error "printf wrap is net-negative on picolibc; codegen should set USE_FULL_PRINTF"
+#endif
+
 #include <cstdarg>
 #include <cstdio>
 
@@ -34,6 +40,9 @@
 
 namespace esphome::esp32 {}
 
+// NOLINTBEGIN(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp,readability-identifier-naming)
+extern "C" {
+
 static constexpr size_t PRINTF_BUFFER_SIZE = 512;
 
 // These stubs are essentially dead code at runtime — ESPHome replaces the
@@ -55,14 +64,16 @@ static int write_printf_buffer(FILE *stream, char *buf, int len) {
   return len;
 }
 
-// NOLINTBEGIN(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp,readability-identifier-naming)
-extern "C" {
-
 int __wrap_vprintf(const char *fmt, va_list ap) {
   char buf[PRINTF_BUFFER_SIZE];
   return write_printf_buffer(stdout, buf, vsnprintf(buf, sizeof(buf), fmt, ap));
 }
 
+int __wrap_vfprintf(FILE *stream, const char *fmt, va_list ap) {
+  char buf[PRINTF_BUFFER_SIZE];
+  return write_printf_buffer(stream, buf, vsnprintf(buf, sizeof(buf), fmt, ap));
+}
+
 int __wrap_printf(const char *fmt, ...) {
   va_list ap;
   va_start(ap, fmt);
@@ -71,11 +82,6 @@ int __wrap_printf(const char *fmt, ...) {
   return len;
 }
 
-int __wrap_vfprintf(FILE *stream, const char *fmt, va_list ap) {
-  char buf[PRINTF_BUFFER_SIZE];
-  return write_printf_buffer(stream, buf, vsnprintf(buf, sizeof(buf), fmt, ap));
-}
-
 int __wrap_fprintf(FILE *stream, const char *fmt, ...) {
   va_list ap;
   va_start(ap, fmt);
diff --git a/esphome/components/esp32_ble/ble_uuid.cpp b/esphome/components/esp32_ble/ble_uuid.cpp
index 334780e3b8..886f8237ad 100644
--- a/esphome/components/esp32_ble/ble_uuid.cpp
+++ b/esphome/components/esp32_ble/ble_uuid.cpp
@@ -104,7 +104,7 @@ ESPBTUUID ESPBTUUID::as_128bit() const {
   } else {
     uuid32 = this->uuid_.uuid.uuid16;
   }
-  for (uint8_t i = 0; i < this->uuid_.len; i++) {
+  for (uint16_t i = 0; i < this->uuid_.len; i++) {
     data[12 + i] = ((uuid32 >> i * 8) & 0xFF);
   }
   return ESPBTUUID::from_raw(data);
diff --git a/esphome/components/esp32_hosted/__init__.py b/esphome/components/esp32_hosted/__init__.py
index 1619a845d8..eca7c24b10 100644
--- a/esphome/components/esp32_hosted/__init__.py
+++ b/esphome/components/esp32_hosted/__init__.py
@@ -246,9 +246,10 @@ async def to_code(config):
     idf_ver = esp32.idf_version()
     os.environ["ESP_IDF_VERSION"] = f"{idf_ver.major}.{idf_ver.minor}"
     if idf_ver >= cv.Version(5, 5, 0):
-        esp32.add_idf_component(name="espressif/esp_wifi_remote", ref="1.4.0")
-        esp32.add_idf_component(name="espressif/eppp_link", ref="1.1.4")
-        esp32.add_idf_component(name="espressif/esp_hosted", ref="2.12.1")
+        esp32.add_idf_component(name="espressif/esp_wifi_remote", ref="1.5.1")
+        esp32.add_idf_component(name="espressif/wifi_remote_over_eppp", ref="0.3.2")
+        esp32.add_idf_component(name="espressif/eppp_link", ref="1.1.5")
+        esp32.add_idf_component(name="espressif/esp_hosted", ref="2.12.6")
     else:
         esp32.add_idf_component(name="espressif/esp_wifi_remote", ref="0.13.0")
         esp32.add_idf_component(name="espressif/eppp_link", ref="0.2.0")
diff --git a/esphome/components/esp32_touch/esp32_touch.cpp b/esphome/components/esp32_touch/esp32_touch.cpp
index e44bc807e9..54bbbe52ed 100644
--- a/esphome/components/esp32_touch/esp32_touch.cpp
+++ b/esphome/components/esp32_touch/esp32_touch.cpp
@@ -216,6 +216,7 @@ void ESP32TouchComponent::setup() {
   // Do initial oneshot scans to populate baseline values
   for (uint32_t i = 0; i < ONESHOT_SCAN_COUNT; i++) {
     err = touch_sensor_trigger_oneshot_scanning(this->sens_handle_, ONESHOT_SCAN_TIMEOUT_MS);
+    App.feed_wdt();  // 3 scans with 2s timeout might exceed WDT, so feed it here to be safe
     if (err != ESP_OK) {
       ESP_LOGW(TAG, "Oneshot scan %" PRIu32 " failed: %s", i, esp_err_to_name(err));
     }
diff --git a/esphome/components/esp8266/__init__.py b/esphome/components/esp8266/__init__.py
index bef7e36470..3c2806a307 100644
--- a/esphome/components/esp8266/__init__.py
+++ b/esphome/components/esp8266/__init__.py
@@ -94,6 +94,18 @@ def set_core_data(config):
 
 
 def get_download_types(storage_json):
+    """Binary-download entries for a built ESP8266 firmware.
+
+    Used by:
+    - esphome.dashboard (legacy "Download .bin" button)
+    - device-builder (esphome/device-builder) — same dispatch via
+      ``importlib.import_module(f"esphome.components.{platform}")``
+      then ``module.get_download_types(storage)``. The contract is
+      "returns ``list[dict]`` with at least ``title`` /
+      ``description`` / ``file`` / ``download`` keys"; please keep
+      the shape stable so the new dashboard's download panel
+      doesn't have to special-case per-platform schemas.
+    """
     return [
         {
             "title": "Standard format",
@@ -314,6 +326,11 @@ async def to_code(config):
         for symbol in ("vprintf", "printf", "fprintf"):
             cg.add_build_flag(f"-Wl,--wrap={symbol}")
 
+    # Wrap Arduino's millis() so all callers (including Arduino libraries and ISR
+    # handlers) use our fast accumulator instead of the expensive 4x 64-bit multiply
+    # implementation in the Arduino ESP8266 core.
+    cg.add_build_flag("-Wl,--wrap=millis")
+
     cg.add_platformio_option("board_build.flash_mode", config[CONF_BOARD_FLASH_MODE])
 
     ver: cv.Version = CORE.data[KEY_CORE][KEY_FRAMEWORK_VERSION]
diff --git a/esphome/components/esp8266/core.cpp b/esphome/components/esp8266/core.cpp
index 159ec20e77..b9ad4082e9 100644
--- a/esphome/components/esp8266/core.cpp
+++ b/esphome/components/esp8266/core.cpp
@@ -3,45 +3,12 @@
 #include "core.h"
 #include "esphome/core/defines.h"
 #include "esphome/core/hal.h"
-#include "esphome/core/time_64.h"
-#include "esphome/core/helpers.h"
-#include "preferences.h"
 #include <Arduino.h>
-#include <core_esp8266_features.h>
-
-extern "C" {
-#include <user_interface.h>
-}
 
 namespace esphome {
 
-void HOT yield() { ::yield(); }
-uint32_t IRAM_ATTR HOT millis() { return ::millis(); }
-uint64_t millis_64() { return Millis64Impl::compute(::millis()); }
-void HOT delay(uint32_t ms) { ::delay(ms); }
-uint32_t IRAM_ATTR HOT micros() { return ::micros(); }
-void IRAM_ATTR HOT delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
-void arch_restart() {
-  system_restart();
-  // restart() doesn't always end execution
-  while (true) {  // NOLINT(clang-diagnostic-unreachable-code)
-    yield();
-  }
-}
-void arch_init() {}
-void HOT arch_feed_wdt() { system_soft_wdt_feed(); }
-
-uint8_t progmem_read_byte(const uint8_t *addr) {
-  return pgm_read_byte(addr);  // NOLINT
-}
-const char *progmem_read_ptr(const char *const *addr) {
-  return reinterpret_cast<const char *>(pgm_read_ptr(addr));  // NOLINT
-}
-uint16_t progmem_read_uint16(const uint16_t *addr) {
-  return pgm_read_word(addr);  // NOLINT
-}
-uint32_t IRAM_ATTR HOT arch_get_cpu_cycle_count() { return esp_get_cycle_count(); }
-uint32_t arch_get_cpu_freq_hz() { return F_CPU; }
+// HAL functions live in hal.cpp. This file keeps only the ESP8266-specific
+// firmware bootstrap (Tasmota OTA magic bytes, optional GPIO pre-init).
 
 void force_link_symbols() {
   // Tasmota uses magic bytes in the binary to check if an OTA firmware is compatible
diff --git a/esphome/components/esp8266/gpio.cpp b/esphome/components/esp8266/gpio.cpp
index 659233443e..a85f054dfe 100644
--- a/esphome/components/esp8266/gpio.cpp
+++ b/esphome/components/esp8266/gpio.cpp
@@ -140,6 +140,7 @@ void IRAM_ATTR ISRInternalGPIOPin::digital_write(bool value) {
 
 void IRAM_ATTR ISRInternalGPIOPin::clear_interrupt() {
   auto *arg = reinterpret_cast<ISRPinArg *>(arg_);
+  // NOLINTNEXTLINE(clang-analyzer-core.FixedAddressDereference) -- GPIO_REG_WRITE is MMIO at a fixed address
   GPIO_REG_WRITE(GPIO_STATUS_W1TC_ADDRESS, 1UL << arg->pin);
 }
 
diff --git a/esphome/components/esp8266/hal.cpp b/esphome/components/esp8266/hal.cpp
new file mode 100644
index 0000000000..e8f472dc8a
--- /dev/null
+++ b/esphome/components/esp8266/hal.cpp
@@ -0,0 +1,111 @@
+#ifdef USE_ESP8266
+
+#include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
+
+#include <Arduino.h>
+#include <core_esp8266_features.h>
+
+extern "C" {
+#include <user_interface.h>
+}
+
+// Empty esp8266 namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// esp8266 component's API.
+namespace esphome::esp8266 {}  // namespace esphome::esp8266
+
+namespace esphome {
+
+// yield(), micros(), millis_64(), delayMicroseconds(), arch_feed_wdt(),
+// progmem_read_*() are inlined in components/esp8266/hal.h.
+//
+// Fast accumulator replacement for Arduino's millis() (~3.3 μs via 4× 64-bit
+// multiplies on the LX106). Tracks a running ms counter from 32-bit
+// system_get_time() deltas using pure 32-bit ops. Installed as __wrap_millis
+// (via -Wl,--wrap=millis) so Arduino libs and IRAM_ATTR ISR handlers (e.g.
+// Wiegand, ZyAura) also get the fast version. xt_rsil(15) guards the static
+// state against ISR re-entry; the critical section is bounded (≤10 while-loop
+// iterations, ~100 ns on the common path, or a constant-time /1000 ~2.5 μs on
+// the rare path — well under WiFi's ~10 μs ISR latency budget). NMIs (level
+// >15) are not masked, but the ESP8266 SDK's NMI handlers don't call millis().
+//
+// system_get_time() wraps every ~71.6 min; unsigned (now_us - last_us) handles
+// one wrap. The main loop calls millis() at 60+ Hz, so delta stays tiny — a
+// >71 min block would trip the watchdog long before it could matter here.
+static constexpr uint32_t MILLIS_RARE_PATH_THRESHOLD_US = 10000;
+static constexpr uint32_t US_PER_MS = 1000;
+
+uint32_t IRAM_ATTR HOT millis() {
+  // Struct packs the three statics so the compiler loads one base address
+  // instead of three separate literal pool entries (saves ~8 bytes IRAM).
+  static struct {
+    uint32_t cache;
+    uint32_t remainder;
+    uint32_t last_us;
+  } state = {0, 0, 0};
+  uint32_t ps = xt_rsil(15);
+  uint32_t now_us = system_get_time();
+  uint32_t delta = now_us - state.last_us;
+  state.last_us = now_us;
+  state.remainder += delta;
+  if (state.remainder >= MILLIS_RARE_PATH_THRESHOLD_US) {
+    // Rare path: large gap (WiFi scan, boot, long block). Constant-time
+    // conversion keeps the critical section bounded.
+    uint32_t ms = state.remainder / US_PER_MS;
+    state.cache += ms;
+    // Reuse ms instead of `remainder %= US_PER_MS` — `%` would compile to a
+    // second __umodsi3 call on the LX106 (no hardware divide).
+    state.remainder -= ms * US_PER_MS;
+  } else {
+    // Common path: small gap. At most ~10 iterations since remainder was
+    // < threshold (10 ms) on entry and delta adds at most one more threshold
+    // before exiting this branch.
+    while (state.remainder >= US_PER_MS) {
+      state.cache++;
+      state.remainder -= US_PER_MS;
+    }
+  }
+  uint32_t result = state.cache;
+  xt_wsr_ps(ps);
+  return result;
+}
+
+// Poll-based delay that avoids ::delay() — Arduino's __delay has an intra-object
+// call to the original millis() that --wrap can't intercept, so calling ::delay()
+// would keep the slow Arduino millis body alive in IRAM. optimistic_yield still
+// enters esp_schedule()/esp_suspend_within_cont() via yield(), so SDK tasks and
+// WiFi run correctly. Theoretically less power-efficient than Arduino's
+// os_timer-based delay() for long waits, but nearly all ESPHome delays are short
+// (sensor/I²C/SPI settling in the 1–100 ms range) where the difference is
+// negligible.
+void HOT delay(uint32_t ms) {
+  if (ms == 0) {
+    optimistic_yield(1000);
+    return;
+  }
+  uint32_t start = millis();
+  while (millis() - start < ms) {
+    optimistic_yield(1000);
+  }
+}
+
+void arch_restart() {
+  system_restart();
+  // restart() doesn't always end execution
+  while (true) {  // NOLINT(clang-diagnostic-unreachable-code)
+    yield();
+  }
+}
+
+}  // namespace esphome
+
+// Linker wrap: redirect all ::millis() calls (Arduino libs, ISRs) to our accumulator.
+// Requires -Wl,--wrap=millis in build flags (added by __init__.py).
+// NOLINTNEXTLINE(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp,readability-identifier-naming)
+extern "C" uint32_t IRAM_ATTR __wrap_millis() { return esphome::millis(); }
+// Note: Arduino's init() registers a 60-second overflow timer for micros64().
+// We leave it running — wrapping init() as a no-op would break micros64()'s
+// overflow tracking, and the timer's cost is negligible (~3 μs per 60 s).
+
+#endif  // USE_ESP8266
diff --git a/esphome/components/esp8266/hal.h b/esphome/components/esp8266/hal.h
new file mode 100644
index 0000000000..effa9c9371
--- /dev/null
+++ b/esphome/components/esp8266/hal.h
@@ -0,0 +1,73 @@
+#pragma once
+
+#ifdef USE_ESP8266
+
+#include <c_types.h>
+#include <core_esp8266_features.h>
+#include <cstdint>
+#include <pgmspace.h>
+
+#include "esphome/core/time_64.h"
+
+#ifndef PROGMEM
+#define PROGMEM ICACHE_RODATA_ATTR
+#endif
+
+// Forward decls from Arduino's <Arduino.h> for the inline wrappers below.
+// NOLINTBEGIN(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+extern "C" void yield(void);
+extern "C" void delay(unsigned long ms);
+extern "C" unsigned long micros(void);
+extern "C" unsigned long millis(void);
+// NOLINTEND(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+
+// Forward decl from <user_interface.h> for arch_feed_wdt() inline below.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+extern "C" void system_soft_wdt_feed(void);
+
+namespace esphome::esp8266 {}
+
+namespace esphome {
+
+// Forward decl from helpers.h so this header stays cheap.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+void delay_microseconds_safe(uint32_t us);
+
+/// Returns true when executing inside an interrupt handler.
+/// ESP8266 has no reliable single-register ISR detection: PS.INTLEVEL is
+/// non-zero both in a real ISR and when user code masks interrupts.  The
+/// ESP8266 wake path is context-agnostic (wake_loop_impl uses esp_schedule
+/// which is ISR-safe) so this helper is unused on this platform.
+__attribute__((always_inline)) inline bool in_isr_context() { return false; }
+
+__attribute__((always_inline)) inline void yield() { ::yield(); }
+__attribute__((always_inline)) inline uint32_t micros() { return static_cast<uint32_t>(::micros()); }
+void delay(uint32_t ms);
+uint32_t millis();
+__attribute__((always_inline)) inline uint64_t millis_64() { return Millis64Impl::compute(millis()); }
+
+// ESP8266: pgm_read_* does aligned 32-bit flash reads on Harvard architecture.
+// Inline-forward to the platform macros so the wrappers themselves don't
+// occupy IRAM/flash on every call site.
+__attribute__((always_inline)) inline uint8_t progmem_read_byte(const uint8_t *addr) {
+  return pgm_read_byte(addr);  // NOLINT
+}
+__attribute__((always_inline)) inline const char *progmem_read_ptr(const char *const *addr) {
+  return reinterpret_cast<const char *>(pgm_read_ptr(addr));  // NOLINT
+}
+__attribute__((always_inline)) inline uint16_t progmem_read_uint16(const uint16_t *addr) {
+  return pgm_read_word(addr);  // NOLINT
+}
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
+__attribute__((always_inline)) inline void arch_feed_wdt() { system_soft_wdt_feed(); }
+__attribute__((always_inline)) inline void arch_init() {}
+// esp_get_cycle_count() declared in <core_esp8266_features.h>; F_CPU is a
+// compiler-driven macro from the ESP8266 Arduino board defs (-DF_CPU=...).
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() { return esp_get_cycle_count(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_freq_hz() { return F_CPU; }
+
+}  // namespace esphome
+
+#endif  // USE_ESP8266
diff --git a/esphome/components/esp8266/preferences.cpp b/esphome/components/esp8266/preferences.cpp
index f444f03555..696f83bce1 100644
--- a/esphome/components/esp8266/preferences.cpp
+++ b/esphome/components/esp8266/preferences.cpp
@@ -51,7 +51,7 @@ static inline bool esp_rtc_user_mem_read(uint32_t index, uint32_t *dest) {
   if (index >= ESP_RTC_USER_MEM_SIZE_WORDS) {
     return false;
   }
-  *dest = ESP_RTC_USER_MEM[index];  // NOLINT(performance-no-int-to-ptr)
+  *dest = ESP_RTC_USER_MEM[index];  // NOLINT(performance-no-int-to-ptr,clang-analyzer-core.FixedAddressDereference)
   return true;
 }
 
@@ -64,7 +64,7 @@ static inline bool esp_rtc_user_mem_write(uint32_t index, uint32_t value) {
   }
 
   auto *ptr = &ESP_RTC_USER_MEM[index];  // NOLINT(performance-no-int-to-ptr)
-  *ptr = value;
+  *ptr = value;                          // NOLINT(clang-analyzer-core.FixedAddressDereference)
   return true;
 }
 
diff --git a/esphome/components/esphome/ota/__init__.py b/esphome/components/esphome/ota/__init__.py
index bfa5ffb55c..ee3b7f0c20 100644
--- a/esphome/components/esphome/ota/__init__.py
+++ b/esphome/components/esphome/ota/__init__.py
@@ -16,11 +16,13 @@ from esphome.const import (
     CONF_SAFE_MODE,
     CONF_VERSION,
 )
-from esphome.core import coroutine_with_priority
+from esphome.core import CORE, coroutine_with_priority
 from esphome.coroutine import CoroPriority
 import esphome.final_validate as fv
 from esphome.types import ConfigType
 
+CONF_ALLOW_PARTITION_ACCESS = "allow_partition_access"
+
 _LOGGER = logging.getLogger(__name__)
 
 
@@ -75,6 +77,10 @@ def ota_esphome_final_validate(config):
                 merged_ota_esphome_configs_by_port[conf_port] = merge_config(
                     merged_ota_esphome_configs_by_port[conf_port], ota_conf
                 )
+            if ota_conf.get(CONF_ALLOW_PARTITION_ACCESS) and not CORE.is_esp32:
+                raise cv.Invalid(
+                    f"{CONF_ALLOW_PARTITION_ACCESS} is only supported on the esp32"
+                )
         else:
             new_ota_conf.append(ota_conf)
 
@@ -125,6 +131,7 @@ CONFIG_SCHEMA = cv.All(
                 ln882x=8820,
                 rtl87xx=8892,
             ): cv.port,
+            cv.Optional(CONF_ALLOW_PARTITION_ACCESS, default=False): cv.boolean,
             cv.Optional(CONF_PASSWORD): cv.string,
             cv.Optional(CONF_NUM_ATTEMPTS): cv.invalid(
                 f"'{CONF_SAFE_MODE}' (and its related configuration variables) has moved from 'ota' to its own component. See https://esphome.io/components/safe_mode"
@@ -159,6 +166,10 @@ async def to_code(config: ConfigType) -> None:
         if config[CONF_PASSWORD]:
             cg.add(var.set_auth_password(config[CONF_PASSWORD]))
     cg.add_define("USE_OTA_VERSION", config[CONF_VERSION])
+
+    if config.get(CONF_ALLOW_PARTITION_ACCESS):
+        cg.add_define("USE_OTA_PARTITIONS")
+
     # Build flag so lwip_fast_select.c (a .c file that can't include defines.h) sees it.
     cg.add_build_flag("-DUSE_OTA_PLATFORM_ESPHOME")
 
diff --git a/esphome/components/esphome/ota/ota_esphome.cpp b/esphome/components/esphome/ota/ota_esphome.cpp
index 47f661a8ea..3ce3f2302d 100644
--- a/esphome/components/esphome/ota/ota_esphome.cpp
+++ b/esphome/components/esphome/ota/ota_esphome.cpp
@@ -87,6 +87,10 @@ void ESPHomeOTAComponent::setup() {
   // no wakes fire and loop() falls back to the self-disable safety net.
   esphome_fast_select_set_ota_listener_sock(esphome_lwip_get_sock(this->server_->get_fd()));
 #endif
+
+#ifdef USE_OTA_PARTITIONS
+  ota::get_running_app_position(this->running_app_offset_, this->running_app_size_);
+#endif
 }
 
 void ESPHomeOTAComponent::dump_config() {
@@ -100,6 +104,29 @@ void ESPHomeOTAComponent::dump_config() {
     ESP_LOGCONFIG(TAG, "  Password configured");
   }
 #endif
+#ifdef USE_OTA_PARTITIONS
+  ESP_LOGCONFIG(TAG,
+                "  Partition access allowed\n"
+                "  Running app:\n"
+                "    Partition address: 0x%X\n"
+                "    Used size: %zu bytes (0x%X)",
+                this->running_app_offset_, this->running_app_size_, this->running_app_size_);
+
+#ifdef USE_ESP32
+  ESP_LOGCONFIG(TAG,
+                "  Partition table:\n"
+                "    %-12s %-4s %-8s %-10s %-10s",
+                "Name", "Type", "Subtype", "Address", "Size");
+  esp_partition_iterator_t it = esp_partition_find(ESP_PARTITION_TYPE_ANY, ESP_PARTITION_SUBTYPE_ANY, NULL);
+  while (it != NULL) {
+    const esp_partition_t *partition = esp_partition_get(it);
+    ESP_LOGCONFIG(TAG, "    %-12s 0x%-2X 0x%-6X 0x%-8" PRIX32 " 0x%-8" PRIX32, partition->label, partition->type,
+                  partition->subtype, partition->address, partition->size);
+    it = esp_partition_next(it);
+  }
+  esp_partition_iterator_release(it);
+#endif
+#endif
 }
 
 void ESPHomeOTAComponent::loop() {
@@ -114,8 +141,11 @@ void ESPHomeOTAComponent::loop() {
   this->handle_handshake_();
 }
 
-static const uint8_t FEATURE_SUPPORTS_COMPRESSION = 0x01;
-static const uint8_t FEATURE_SUPPORTS_SHA256_AUTH = 0x02;
+static constexpr uint8_t CLIENT_FEATURE_SUPPORTS_COMPRESSION = 0x01;
+static constexpr uint8_t CLIENT_FEATURE_SUPPORTS_SHA256_AUTH = 0x02;
+static constexpr uint8_t CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL = 0x04;
+static constexpr uint8_t SERVER_FEATURE_SUPPORTS_COMPRESSION = 0x01;
+static constexpr uint8_t SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS = 0x02;
 
 void ESPHomeOTAComponent::handle_handshake_() {
   /// Handle the OTA handshake and authentication.
@@ -201,16 +231,33 @@ void ESPHomeOTAComponent::handle_handshake_() {
       this->ota_features_ = this->handshake_buf_[0];
       ESP_LOGV(TAG, "Features: 0x%02X", this->ota_features_);
       this->transition_ota_state_(OTAState::FEATURE_ACK);
-      this->handshake_buf_[0] =
-          ((this->ota_features_ & FEATURE_SUPPORTS_COMPRESSION) != 0 && this->backend_->supports_compression())
-              ? ota::OTA_RESPONSE_SUPPORTS_COMPRESSION
-              : ota::OTA_RESPONSE_HEADER_OK;
+
+      const bool supports_compression =
+          (this->ota_features_ & CLIENT_FEATURE_SUPPORTS_COMPRESSION) != 0 && this->backend_->supports_compression();
+
+      // Compose the feature-ack response. When the client negotiates the extended protocol we emit
+      // a 2-byte response (marker + server feature flags); otherwise we emit the single-byte
+      // legacy response.
+      this->extended_proto_ = (this->ota_features_ & CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL) != 0;
+      if (this->extended_proto_) {
+        static_assert(HANDSHAKE_BUF_SIZE >= 2, "handshake_buf_ must hold the 2-byte extended-protocol feature ack");
+        this->handshake_buf_[0] = ota::OTA_RESPONSE_FEATURE_FLAGS;
+        this->handshake_buf_[1] = (supports_compression ? SERVER_FEATURE_SUPPORTS_COMPRESSION : 0);
+#ifdef USE_OTA_PARTITIONS
+        this->handshake_buf_[1] |= SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS;
+#endif
+      } else {
+        this->handshake_buf_[0] =
+            supports_compression ? ota::OTA_RESPONSE_SUPPORTS_COMPRESSION : ota::OTA_RESPONSE_HEADER_OK;
+      }
       [[fallthrough]];
     }
 
     case OTAState::FEATURE_ACK: {
-      // Acknowledge header - 1 byte
-      if (!this->try_write_(1, LOG_STR("ack feature"))) {
+      static constexpr size_t STANDARD_PROTO_ACK_SIZE = 1;
+      static constexpr size_t EXTENDED_PROTO_ACK_SIZE = 2;
+      const size_t ack_size = this->extended_proto_ ? EXTENDED_PROTO_ACK_SIZE : STANDARD_PROTO_ACK_SIZE;
+      if (!this->try_write_(ack_size, LOG_STR("ack feature"))) {
         return;
       }
 #ifdef USE_OTA_PASSWORD
@@ -292,9 +339,11 @@ void ESPHomeOTAComponent::handle_data_() {
   bool update_started = false;
   size_t total = 0;
   uint32_t last_progress = 0;
+  uint32_t last_data_ms = 0;
   uint8_t buf[OTA_BUFFER_SIZE];
   char *sbuf = reinterpret_cast<char *>(buf);
   size_t ota_size;
+  ota::OTAType ota_type = ota::OTA_TYPE_UPDATE_APP;
 #if USE_OTA_VERSION == 2
   size_t size_acknowledged = 0;
 #endif
@@ -310,6 +359,16 @@ void ESPHomeOTAComponent::handle_data_() {
   // Acknowledge auth OK - 1 byte
   this->write_byte_(ota::OTA_RESPONSE_AUTH_OK);
 
+  if (this->extended_proto_) {
+    // Read ota type, 1 byte
+    if (!this->readall_(buf, 1)) {
+      this->log_read_error_(LOG_STR("OTA type"));
+      goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
+    }
+    ota_type = static_cast<ota::OTAType>(buf[0]);
+  }
+  ESP_LOGV(TAG, "OTA type is 0x%02x", ota_type);
+
   // Read size, 4 bytes MSB first
   if (!this->readall_(buf, 4)) {
     this->log_read_error_(LOG_STR("size"));
@@ -319,6 +378,13 @@ void ESPHomeOTAComponent::handle_data_() {
              (static_cast<size_t>(buf[2]) << 8) | buf[3];
   ESP_LOGV(TAG, "Size is %u bytes", ota_size);
 
+#ifndef USE_OTA_PARTITIONS
+  if (ota_type != ota::OTA_TYPE_UPDATE_APP) {
+    error_code = ota::OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+    goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
+  }
+#endif
+
   // Now that we've passed authentication and are actually
   // starting the update, set the warning status and notify
   // listeners. This ensures that port scanners do not
@@ -329,8 +395,8 @@ void ESPHomeOTAComponent::handle_data_() {
   this->notify_state_(ota::OTA_STARTED, 0.0f, 0);
 #endif
 
-  // This will block for a few seconds as it locks flash
-  error_code = this->backend_->begin(ota_size);
+  // begin() may block for a few seconds while it locks flash.
+  error_code = this->backend_->begin(ota_size, ota_type);
   if (error_code != ota::OTA_RESPONSE_OK)
     goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
   update_started = true;
@@ -350,8 +416,18 @@ void ESPHomeOTAComponent::handle_data_() {
   // Acknowledge MD5 OK - 1 byte
   this->write_byte_(ota::OTA_RESPONSE_BIN_MD5_OK);
 
+  // Track when we last received data so a silently-vanished peer (no FIN/RST
+  // delivered, e.g. uploader killed mid-transfer or NAT/router dropped state)
+  // can't wedge the device indefinitely. Without this, the loop only exits
+  // on actual data, EOF, or a non-EWOULDBLOCK error from read(), and lwIP
+  // TCP keepalive isn't enabled here.
+  last_data_ms = millis();
   while (total < ota_size) {
-    // TODO: timeout check
+    if (millis() - last_data_ms > OTA_SOCKET_TIMEOUT_DATA) {
+      ESP_LOGW(TAG, "No data received for %u ms", (unsigned) OTA_SOCKET_TIMEOUT_DATA);
+      error_code = ota::OTA_RESPONSE_ERROR_UNKNOWN;
+      goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
+    }
     size_t remaining = ota_size - total;
     size_t requested = remaining < OTA_BUFFER_SIZE ? remaining : OTA_BUFFER_SIZE;
     ssize_t read = this->client_->read(buf, requested);
@@ -369,6 +445,7 @@ void ESPHomeOTAComponent::handle_data_() {
       goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
     }
 
+    last_data_ms = millis();
     error_code = this->backend_->write(buf, read);
     if (error_code != ota::OTA_RESPONSE_OK) {
       ESP_LOGW(TAG, "Flash write err %d", error_code);
@@ -421,6 +498,13 @@ void ESPHomeOTAComponent::handle_data_() {
   this->notify_state_(ota::OTA_COMPLETED, 100.0f, 0);
 #endif
   delay(100);  // NOLINT
+#ifdef USE_OTA_PARTITIONS
+  if (ota_type == ota::OTA_TYPE_UPDATE_PARTITION_TABLE) {
+    // Skip on_safe_shutdown: nvs_flash_deinit() has already invalidated open NVS handles, so
+    // preferences flush would emit ESP_ERR_NVS_INVALID_HANDLE for every entry. Reboot directly.
+    App.reboot();
+  }
+#endif
   App.safe_reboot();
 
 error:
@@ -604,7 +688,7 @@ void ESPHomeOTAComponent::yield_and_feed_watchdog_() {
 void ESPHomeOTAComponent::log_auth_warning_(const LogString *msg) { ESP_LOGW(TAG, "Auth: %s", LOG_STR_ARG(msg)); }
 
 bool ESPHomeOTAComponent::select_auth_type_() {
-  bool client_supports_sha256 = (this->ota_features_ & FEATURE_SUPPORTS_SHA256_AUTH) != 0;
+  bool client_supports_sha256 = (this->ota_features_ & CLIENT_FEATURE_SUPPORTS_SHA256_AUTH) != 0;
 
   // Require SHA256
   if (!client_supports_sha256) {
diff --git a/esphome/components/esphome/ota/ota_esphome.h b/esphome/components/esphome/ota/ota_esphome.h
index 53288fc000..0053ca6969 100644
--- a/esphome/components/esphome/ota/ota_esphome.h
+++ b/esphome/components/esphome/ota/ota_esphome.h
@@ -97,8 +97,13 @@ class ESPHomeOTAComponent final : public ota::OTAComponent {
   ota::OTABackendPtr backend_;
 
   uint32_t client_connect_time_{0};
+  static constexpr size_t HANDSHAKE_BUF_SIZE = 5;
+#ifdef USE_OTA_PARTITIONS
+  uint32_t running_app_offset_{0};
+  size_t running_app_size_{0};
+#endif
   uint16_t port_;
-  uint8_t handshake_buf_[5];
+  uint8_t handshake_buf_[HANDSHAKE_BUF_SIZE];
   OTAState ota_state_{OTAState::IDLE};
   uint8_t handshake_buf_pos_{0};
   uint8_t ota_features_{0};
@@ -106,6 +111,7 @@ class ESPHomeOTAComponent final : public ota::OTAComponent {
   uint8_t auth_buf_pos_{0};
   uint8_t auth_type_{0};  // Store auth type to know which hasher to use
 #endif                    // USE_OTA_PASSWORD
+  bool extended_proto_{false};
 };
 
 }  // namespace esphome
diff --git a/esphome/components/espnow/__init__.py b/esphome/components/espnow/__init__.py
index a9624734d0..7861c0affa 100644
--- a/esphome/components/espnow/__init__.py
+++ b/esphome/components/espnow/__init__.py
@@ -26,9 +26,9 @@ espnow_ns = cg.esphome_ns.namespace("espnow")
 ESPNowComponent = espnow_ns.class_("ESPNowComponent", cg.Component)
 
 # Handler interfaces that other components can use to register callbacks
-ESPNowReceivedPacketHandler = espnow_ns.class_("ESPNowReceivedPacketHandler")
+ESPNowReceivePacketHandler = espnow_ns.class_("ESPNowReceivePacketHandler")
 ESPNowUnknownPeerHandler = espnow_ns.class_("ESPNowUnknownPeerHandler")
-ESPNowBroadcastedHandler = espnow_ns.class_("ESPNowBroadcastedHandler")
+ESPNowBroadcastHandler = espnow_ns.class_("ESPNowBroadcastHandler")
 
 ESPNowRecvInfo = espnow_ns.class_("ESPNowRecvInfo")
 ESPNowRecvInfoConstRef = ESPNowRecvInfo.operator("const").operator("ref")
@@ -48,10 +48,10 @@ OnUnknownPeerTrigger = espnow_ns.class_(
     "OnUnknownPeerTrigger", ESPNowHandlerTrigger, ESPNowUnknownPeerHandler
 )
 OnReceiveTrigger = espnow_ns.class_(
-    "OnReceiveTrigger", ESPNowHandlerTrigger, ESPNowReceivedPacketHandler
+    "OnReceiveTrigger", ESPNowHandlerTrigger, ESPNowReceivePacketHandler
 )
-OnBroadcastedTrigger = espnow_ns.class_(
-    "OnBroadcastedTrigger", ESPNowHandlerTrigger, ESPNowBroadcastedHandler
+OnBroadcastTrigger = espnow_ns.class_(
+    "OnBroadcastTrigger", ESPNowHandlerTrigger, ESPNowBroadcastHandler
 )
 
 
@@ -94,7 +94,7 @@ CONFIG_SCHEMA = cv.All(
             ),
             cv.Optional(CONF_ON_BROADCAST): automation.validate_automation(
                 {
-                    cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(OnBroadcastedTrigger),
+                    cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(OnBroadcastTrigger),
                     cv.Optional(CONF_ADDRESS): cv.mac_address,
                 }
             ),
@@ -140,11 +140,11 @@ async def to_code(config):
 
     for on_receive in config.get(CONF_ON_RECEIVE, []):
         trigger = await _trigger_to_code(on_receive)
-        cg.add(var.register_received_handler(trigger))
+        cg.add(var.register_receive_handler(trigger))
 
     for on_receive in config.get(CONF_ON_BROADCAST, []):
         trigger = await _trigger_to_code(on_receive)
-        cg.add(var.register_broadcasted_handler(trigger))
+        cg.add(var.register_broadcast_handler(trigger))
 
 
 # ========================================== A C T I O N S ================================================
diff --git a/esphome/components/espnow/automation.h b/esphome/components/espnow/automation.h
index 0fbb14e388..9c3c55e4ef 100644
--- a/esphome/components/espnow/automation.h
+++ b/esphome/components/espnow/automation.h
@@ -67,6 +67,7 @@ template<typename... Ts> class SendAction : public Action<Ts...>, public Parente
     }
   }
 
+ protected:
   void play(const Ts &...x) override { /* ignore - see play_complex */
   }
 
@@ -75,7 +76,6 @@ template<typename... Ts> class SendAction : public Action<Ts...>, public Parente
     this->error_.stop();
   }
 
- protected:
   ActionList<Ts...> sent_;
   ActionList<Ts...> error_;
 
@@ -89,7 +89,7 @@ template<typename... Ts> class SendAction : public Action<Ts...>, public Parente
 template<typename... Ts> class AddPeerAction : public Action<Ts...>, public Parented<ESPNowComponent> {
   TEMPLATABLE_VALUE(peer_address_t, address);
 
- public:
+ protected:
   void play(const Ts &...x) override {
     peer_address_t address = this->address_.value(x...);
     this->parent_->add_peer(address.data());
@@ -99,7 +99,7 @@ template<typename... Ts> class AddPeerAction : public Action<Ts...>, public Pare
 template<typename... Ts> class DeletePeerAction : public Action<Ts...>, public Parented<ESPNowComponent> {
   TEMPLATABLE_VALUE(peer_address_t, address);
 
- public:
+ protected:
   void play(const Ts &...x) override {
     peer_address_t address = this->address_.value(x...);
     this->parent_->del_peer(address.data());
@@ -107,8 +107,9 @@ template<typename... Ts> class DeletePeerAction : public Action<Ts...>, public P
 };
 
 template<typename... Ts> class SetChannelAction : public Action<Ts...>, public Parented<ESPNowComponent> {
- public:
   TEMPLATABLE_VALUE(uint8_t, channel)
+
+ protected:
   void play(const Ts &...x) override {
     if (this->parent_->is_wifi_enabled()) {
       return;
@@ -125,9 +126,9 @@ class OnReceiveTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_t *,
     memcpy(this->address_, address.data(), ESP_NOW_ETH_ALEN);
   }
 
-  explicit OnReceiveTrigger() : has_address_(false) {}
+  explicit OnReceiveTrigger() {}
 
-  bool on_received(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override {
+  bool on_receive(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override {
     bool match = !this->has_address_ || (memcmp(this->address_, info.src_addr, ESP_NOW_ETH_ALEN) == 0);
     if (!match)
       return false;
@@ -138,7 +139,7 @@ class OnReceiveTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_t *,
 
  protected:
   bool has_address_{false};
-  uint8_t address_[ESP_NOW_ETH_ALEN];
+  uint8_t address_[ESP_NOW_ETH_ALEN]{};
 };
 class OnUnknownPeerTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_t *, uint8_t>,
                              public ESPNowUnknownPeerHandler {
@@ -148,15 +149,15 @@ class OnUnknownPeerTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_
     return false;  // Return false to continue processing other internal handlers
   }
 };
-class OnBroadcastedTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_t *, uint8_t>,
-                             public ESPNowBroadcastedHandler {
+class OnBroadcastTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_t *, uint8_t>,
+                           public ESPNowBroadcastHandler {
  public:
-  explicit OnBroadcastedTrigger(std::array<uint8_t, ESP_NOW_ETH_ALEN> address) : has_address_(true) {
+  explicit OnBroadcastTrigger(std::array<uint8_t, ESP_NOW_ETH_ALEN> address) : has_address_(true) {
     memcpy(this->address_, address.data(), ESP_NOW_ETH_ALEN);
   }
-  explicit OnBroadcastedTrigger() : has_address_(false) {}
+  explicit OnBroadcastTrigger() {}
 
-  bool on_broadcasted(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override {
+  bool on_broadcast(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override {
     bool match = !this->has_address_ || (memcmp(this->address_, info.src_addr, ESP_NOW_ETH_ALEN) == 0);
     if (!match)
       return false;
@@ -167,7 +168,7 @@ class OnBroadcastedTrigger : public Trigger<const ESPNowRecvInfo &, const uint8_
 
  protected:
   bool has_address_{false};
-  uint8_t address_[ESP_NOW_ETH_ALEN];
+  uint8_t address_[ESP_NOW_ETH_ALEN]{};
 };
 
 }  // namespace esphome::espnow
diff --git a/esphome/components/espnow/espnow_component.cpp b/esphome/components/espnow/espnow_component.cpp
index 282287ca83..91d44394e8 100644
--- a/esphome/components/espnow/espnow_component.cpp
+++ b/esphome/components/espnow/espnow_component.cpp
@@ -299,13 +299,13 @@ void ESPNowComponent::loop() {
                    format_hex_pretty_to(hex_buf, packet->packet_.receive.data, packet->packet_.receive.size));
 #endif
           if (memcmp(info.des_addr, ESPNOW_BROADCAST_ADDR, ESP_NOW_ETH_ALEN) == 0) {
-            for (auto *handler : this->broadcasted_handlers_) {
-              if (handler->on_broadcasted(info, packet->packet_.receive.data, packet->packet_.receive.size))
+            for (auto *handler : this->broadcast_handlers_) {
+              if (handler->on_broadcast(info, packet->packet_.receive.data, packet->packet_.receive.size))
                 break;  // If a handler returns true, stop processing further handlers
             }
           } else {
-            for (auto *handler : this->received_handlers_) {
-              if (handler->on_received(info, packet->packet_.receive.data, packet->packet_.receive.size))
+            for (auto *handler : this->receive_handlers_) {
+              if (handler->on_receive(info, packet->packet_.receive.data, packet->packet_.receive.size))
                 break;  // If a handler returns true, stop processing further handlers
             }
           }
diff --git a/esphome/components/espnow/espnow_component.h b/esphome/components/espnow/espnow_component.h
index ee4adc1b4d..ff9581ec2f 100644
--- a/esphome/components/espnow/espnow_component.h
+++ b/esphome/components/espnow/espnow_component.h
@@ -31,8 +31,8 @@ using peer_address_t = std::array<uint8_t, ESP_NOW_ETH_ALEN>;
 enum class ESPNowTriggers : uint8_t {
   TRIGGER_NONE = 0,
   ON_NEW_PEER = 1,
-  ON_RECEIVED = 2,
-  ON_BROADCASTED = 3,
+  ON_RECEIVE = 2,
+  ON_BROADCAST = 3,
   ON_SUCCEED = 10,
   ON_FAILED = 11,
 };
@@ -74,18 +74,18 @@ class ESPNowReceivedPacketHandler {
   /// @param data Pointer to the received data payload
   /// @param size Size of the received data in bytes
   /// @return true if the packet was handled, false otherwise
-  virtual bool on_received(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) = 0;
+  virtual bool on_receive(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) = 0;
 };
-/// Handler interface for receiving broadcasted ESPNow packets
+/// Handler interface for receiving ESPNow broadcast packets
 /// Components should inherit from this class to handle incoming ESPNow data
-class ESPNowBroadcastedHandler {
+class ESPNowBroadcastHandler {
  public:
-  /// Called when a broadcasted ESPNow packet is received
+  /// Called when an ESPNow broadcast packet is received
   /// @param info Information about the received packet (sender MAC, etc.)
   /// @param data Pointer to the received data payload
   /// @param size Size of the received data in bytes
   /// @return true if the packet was handled, false otherwise
-  virtual bool on_broadcasted(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) = 0;
+  virtual bool on_broadcast(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) = 0;
 };
 
 class ESPNowComponent : public Component {
@@ -136,13 +136,11 @@ class ESPNowComponent : public Component {
   esp_err_t send(const uint8_t *peer_address, const uint8_t *payload, size_t size,
                  const send_callback_t &callback = nullptr);
 
-  void register_received_handler(ESPNowReceivedPacketHandler *handler) { this->received_handlers_.push_back(handler); }
+  void register_receive_handler(ESPNowReceivedPacketHandler *handler) { this->receive_handlers_.push_back(handler); }
   void register_unknown_peer_handler(ESPNowUnknownPeerHandler *handler) {
     this->unknown_peer_handlers_.push_back(handler);
   }
-  void register_broadcasted_handler(ESPNowBroadcastedHandler *handler) {
-    this->broadcasted_handlers_.push_back(handler);
-  }
+  void register_broadcast_handler(ESPNowBroadcastHandler *handler) { this->broadcast_handlers_.push_back(handler); }
 
  protected:
   friend void on_data_received(const esp_now_recv_info_t *info, const uint8_t *data, int size);
@@ -156,8 +154,8 @@ class ESPNowComponent : public Component {
   void send_();
 
   std::vector<ESPNowUnknownPeerHandler *> unknown_peer_handlers_;
-  std::vector<ESPNowReceivedPacketHandler *> received_handlers_;
-  std::vector<ESPNowBroadcastedHandler *> broadcasted_handlers_;
+  std::vector<ESPNowReceivedPacketHandler *> receive_handlers_;
+  std::vector<ESPNowBroadcastHandler *> broadcast_handlers_;
 
   std::vector<ESPNowPeer> peers_{};
 
diff --git a/esphome/components/espnow/packet_transport/espnow_transport.cpp b/esphome/components/espnow/packet_transport/espnow_transport.cpp
index 6e4f606466..384e3fe2a9 100644
--- a/esphome/components/espnow/packet_transport/espnow_transport.cpp
+++ b/esphome/components/espnow/packet_transport/espnow_transport.cpp
@@ -26,10 +26,10 @@ void ESPNowTransport::setup() {
            this->peer_address_[5]);
 
   // Register received handler
-  this->parent_->register_received_handler(this);
+  this->parent_->register_receive_handler(this);
 
-  // Register broadcasted handler
-  this->parent_->register_broadcasted_handler(this);
+  // Register broadcast handler
+  this->parent_->register_broadcast_handler(this);
 }
 
 void ESPNowTransport::send_packet(const std::vector<uint8_t> &buf) const {
@@ -56,7 +56,7 @@ void ESPNowTransport::send_packet(const std::vector<uint8_t> &buf) const {
   });
 }
 
-bool ESPNowTransport::on_received(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) {
+bool ESPNowTransport::on_receive(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) {
   ESP_LOGV(TAG, "Received packet of size %u from %02X:%02X:%02X:%02X:%02X:%02X", size, info.src_addr[0],
            info.src_addr[1], info.src_addr[2], info.src_addr[3], info.src_addr[4], info.src_addr[5]);
 
@@ -71,7 +71,7 @@ bool ESPNowTransport::on_received(const ESPNowRecvInfo &info, const uint8_t *dat
   return false;  // Allow other handlers to run
 }
 
-bool ESPNowTransport::on_broadcasted(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) {
+bool ESPNowTransport::on_broadcast(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) {
   ESP_LOGV(TAG, "Received broadcast packet of size %u from %02X:%02X:%02X:%02X:%02X:%02X", size, info.src_addr[0],
            info.src_addr[1], info.src_addr[2], info.src_addr[3], info.src_addr[4], info.src_addr[5]);
 
diff --git a/esphome/components/espnow/packet_transport/espnow_transport.h b/esphome/components/espnow/packet_transport/espnow_transport.h
index d85119db7d..98c33f01fd 100644
--- a/esphome/components/espnow/packet_transport/espnow_transport.h
+++ b/esphome/components/espnow/packet_transport/espnow_transport.h
@@ -15,7 +15,7 @@ namespace espnow {
 class ESPNowTransport : public packet_transport::PacketTransport,
                         public Parented<ESPNowComponent>,
                         public ESPNowReceivedPacketHandler,
-                        public ESPNowBroadcastedHandler {
+                        public ESPNowBroadcastHandler {
  public:
   void setup() override;
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
@@ -25,8 +25,8 @@ class ESPNowTransport : public packet_transport::PacketTransport,
   }
 
   // ESPNow handler interface
-  bool on_received(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override;
-  bool on_broadcasted(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override;
+  bool on_receive(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override;
+  bool on_broadcast(const ESPNowRecvInfo &info, const uint8_t *data, uint8_t size) override;
 
  protected:
   void send_packet(const std::vector<uint8_t> &buf) const override;
diff --git a/esphome/components/ezo/ezo.cpp b/esphome/components/ezo/ezo.cpp
index 2dc65b7d14..bb8fb92f21 100644
--- a/esphome/components/ezo/ezo.cpp
+++ b/esphome/components/ezo/ezo.cpp
@@ -35,7 +35,7 @@ void EZOSensor::update() {
     }
 
     if (!found) {
-      std::unique_ptr<EzoCommand> ezo_command(new EzoCommand);
+      auto ezo_command = make_unique<EzoCommand>();
       ezo_command->command = "R";
       ezo_command->command_type = EzoCommandType::EZO_READ;
       ezo_command->delay_ms = 900;
@@ -162,7 +162,7 @@ void EZOSensor::loop() {
 }
 
 void EZOSensor::add_command_(const char *command, EzoCommandType command_type, uint16_t delay_ms) {
-  std::unique_ptr<EzoCommand> ezo_command(new EzoCommand);
+  auto ezo_command = make_unique<EzoCommand>();
   ezo_command->command = command;
   ezo_command->command_type = command_type;
   ezo_command->delay_ms = delay_ms;
diff --git a/esphome/components/fan/__init__.py b/esphome/components/fan/__init__.py
index 713f20fb95..3949f16d2e 100644
--- a/esphome/components/fan/__init__.py
+++ b/esphome/components/fan/__init__.py
@@ -31,17 +31,19 @@ from esphome.const import (
     CONF_TRIGGER_ID,
     CONF_WEB_SERVER,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, Lambda, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
     queue_entity_register,
     setup_entity,
 )
+from esphome.cpp_generator import LambdaExpression
 
 IS_PLATFORM_COMPONENT = True
 
 fan_ns = cg.esphome_ns.namespace("fan")
 Fan = fan_ns.class_("Fan", cg.EntityBase)
+FanCall = fan_ns.class_("FanCall")
 
 FanDirection = fan_ns.enum("FanDirection", is_class=True)
 FAN_DIRECTION_ENUM = {
@@ -347,17 +349,46 @@ async def fan_turn_off_to_code(config, action_id, template_arg, args):
 )
 async def fan_turn_on_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if (oscillating := config.get(CONF_OSCILLATING)) is not None:
-        template_ = await cg.templatable(oscillating, args, cg.bool_)
-        cg.add(var.set_oscillating(template_))
-    if (speed := config.get(CONF_SPEED)) is not None:
-        template_ = await cg.templatable(speed, args, cg.int_)
-        cg.add(var.set_speed(template_))
-    if (direction := config.get(CONF_DIRECTION)) is not None:
-        template_ = await cg.templatable(direction, args, FanDirection)
-        cg.add(var.set_direction(template_))
-    return var
+
+    # All configured fields are folded into a single stateless lambda whose
+    # constants live in flash; the action stores only a function pointer.
+    FIELDS = (
+        (CONF_OSCILLATING, "set_oscillating", cg.bool_),
+        (CONF_SPEED, "set_speed", cg.int_),
+        (CONF_DIRECTION, "set_direction", FanDirection),
+    )
+
+    # Normalize trigger args to `const std::remove_cvref_t<T> &` so the
+    # apply lambda and any inner field lambdas (generated below via
+    # `process_lambda`) share one parameter spelling that's well-formed for
+    # any T (value, ref, or const-ref). Matches TurnOnAction::ApplyFn.
+    normalized_args = [
+        (cg.RawExpression(f"const std::remove_cvref_t<{cg.safe_exp(t)}> &"), n)
+        for t, n in args
+    ]
+
+    fwd_args = ", ".join(name for _, name in args)
+    body_lines: list[str] = []
+    for conf_key, setter, type_ in FIELDS:
+        if (value := config.get(conf_key)) is None:
+            continue
+        if isinstance(value, Lambda):
+            inner = await cg.process_lambda(value, normalized_args, return_type=type_)
+            body_lines.append(f"call.{setter}(({inner})({fwd_args}));")
+        else:
+            body_lines.append(f"call.{setter}({cg.safe_exp(value)});")
+
+    apply_args = [
+        (FanCall.operator("ref"), "call"),
+        *normalized_args,
+    ]
+    apply_lambda = LambdaExpression(
+        ["\n".join(body_lines)],
+        apply_args,
+        capture="",
+        return_type=cg.void,
+    )
+    return cg.new_Pvariable(action_id, template_arg, paren, apply_lambda)
 
 
 @automation.register_action(
diff --git a/esphome/components/fan/automation.h b/esphome/components/fan/automation.h
index 3ee6f89e55..577c9ce600 100644
--- a/esphome/components/fan/automation.h
+++ b/esphome/components/fan/automation.h
@@ -7,29 +7,31 @@
 namespace esphome {
 namespace fan {
 
+// All configured fields are baked into a single stateless lambda whose
+// constants live in flash. The action only stores one function pointer
+// plus one parent pointer, regardless of how many fields the user set.
+// Trigger args are forwarded to the apply function so user lambdas
+// (e.g. `speed: !lambda "return x;"`) keep working.
+//
+// Trigger args are normalized to `const std::remove_cvref_t<Ts> &...` so
+// the codegen can emit a matching parameter list for both the apply lambda
+// and any inner field lambdas without producing invalid C++ source text
+// (e.g. `const T & &` if Ts already carries a reference, or `const const
+// T &` if Ts already carries a const). This keeps trigger args no-copy
+// regardless of whether the trigger supplies `T`, `T &`, or `const T &`.
 template<typename... Ts> class TurnOnAction : public Action<Ts...> {
  public:
-  explicit TurnOnAction(Fan *state) : state_(state) {}
-
-  TEMPLATABLE_VALUE(bool, oscillating)
-  TEMPLATABLE_VALUE(int, speed)
-  TEMPLATABLE_VALUE(FanDirection, direction)
+  using ApplyFn = void (*)(FanCall &, const std::remove_cvref_t<Ts> &...);
+  TurnOnAction(Fan *state, ApplyFn apply) : state_(state), apply_(apply) {}
 
   void play(const Ts &...x) override {
     auto call = this->state_->turn_on();
-    if (this->oscillating_.has_value()) {
-      call.set_oscillating(this->oscillating_.value(x...));
-    }
-    if (this->speed_.has_value()) {
-      call.set_speed(this->speed_.value(x...));
-    }
-    if (this->direction_.has_value()) {
-      call.set_direction(this->direction_.value(x...));
-    }
+    this->apply_(call, x...);
     call.perform();
   }
 
   Fan *state_;
+  ApplyFn apply_;
 };
 
 template<typename... Ts> class TurnOffAction : public Action<Ts...> {
diff --git a/esphome/components/feedback/feedback_cover.cpp b/esphome/components/feedback/feedback_cover.cpp
index 1dff210cd6..1139e6fa18 100644
--- a/esphome/components/feedback/feedback_cover.cpp
+++ b/esphome/components/feedback/feedback_cover.cpp
@@ -3,11 +3,12 @@
 #include "esphome/core/log.h"
 #include "esphome/core/application.h"
 
-namespace esphome {
-namespace feedback {
+namespace esphome::feedback {
 
 static const char *const TAG = "feedback.cover";
 
+static constexpr uint32_t DIRECTION_CHANGE_TIMEOUT_ID = 1;
+
 using namespace esphome::cover;
 
 void FeedbackCover::setup() {
@@ -37,7 +38,7 @@ void FeedbackCover::setup() {
   }
 #endif
 
-  this->last_recompute_time_ = this->start_dir_time_ = millis();
+  this->last_recompute_time_ = this->start_dir_time_ = App.get_loop_component_start_time();
 }
 
 CoverTraits FeedbackCover::get_traits() {
@@ -135,7 +136,7 @@ void FeedbackCover::set_close_endstop(binary_sensor::BinarySensor *close_endstop
 #endif
 
 void FeedbackCover::endstop_reached_(bool open_endstop) {
-  const uint32_t now = millis();
+  const uint32_t now = App.get_loop_component_start_time();
 
   this->position = open_endstop ? COVER_OPEN : COVER_CLOSED;
 
@@ -174,7 +175,7 @@ void FeedbackCover::set_current_operation_(cover::CoverOperation operation, bool
   if (!is_triggered || (this->open_feedback_ == nullptr || this->close_feedback_ == nullptr))
 #endif
   {
-    auto now = millis();
+    const uint32_t now = App.get_loop_component_start_time();
     this->current_operation = operation;
     this->start_dir_time_ = this->last_recompute_time_ = now;
     this->publish_state();
@@ -306,7 +307,7 @@ void FeedbackCover::control(const CoverCall &call) {
 
 void FeedbackCover::stop_prev_trigger_() {
   if (this->direction_change_waittime_.has_value()) {
-    this->cancel_timeout("direction_change");
+    this->cancel_timeout(DIRECTION_CHANGE_TIMEOUT_ID);
   }
   if (this->prev_command_trigger_ != nullptr) {
     this->prev_command_trigger_->stop_action();
@@ -374,12 +375,10 @@ void FeedbackCover::start_direction_(CoverOperation dir) {
   // check if we have a wait time
   if (this->direction_change_waittime_.has_value() && dir != COVER_OPERATION_IDLE &&
       this->current_operation != COVER_OPERATION_IDLE && dir != this->current_operation) {
+    const uint32_t waittime = *this->direction_change_waittime_;
     ESP_LOGD(TAG, "'%s' - Reversing direction.", this->name_.c_str());
     this->start_direction_(COVER_OPERATION_IDLE);
-
-    this->set_timeout("direction_change", *this->direction_change_waittime_,
-                      [this, dir]() { this->start_direction_(dir); });
-
+    this->set_timeout(DIRECTION_CHANGE_TIMEOUT_ID, waittime, [this, dir]() { this->start_direction_(dir); });
   } else {
     this->set_current_operation_(dir, true);
     this->prev_command_trigger_ = trig;
@@ -395,7 +394,7 @@ void FeedbackCover::recompute_position_() {
   if (this->current_operation == COVER_OPERATION_IDLE)
     return;
 
-  const uint32_t now = millis();
+  const uint32_t now = App.get_loop_component_start_time();
   float dir;
   float action_dur;
   float min_pos;
@@ -451,5 +450,4 @@ void FeedbackCover::recompute_position_() {
   this->last_recompute_time_ = now;
 }
 
-}  // namespace feedback
-}  // namespace esphome
+}  // namespace esphome::feedback
diff --git a/esphome/components/feedback/feedback_cover.h b/esphome/components/feedback/feedback_cover.h
index 6be8939413..ed6f7490f8 100644
--- a/esphome/components/feedback/feedback_cover.h
+++ b/esphome/components/feedback/feedback_cover.h
@@ -8,8 +8,7 @@
 #endif
 #include "esphome/components/cover/cover.h"
 
-namespace esphome {
-namespace feedback {
+namespace esphome::feedback {
 
 class FeedbackCover : public cover::Cover, public Component {
  public:
@@ -85,5 +84,4 @@ class FeedbackCover : public cover::Cover, public Component {
   uint32_t update_interval_{1000};
 };
 
-}  // namespace feedback
-}  // namespace esphome
+}  // namespace esphome::feedback
diff --git a/esphome/components/haier/hon_climate.cpp b/esphome/components/haier/hon_climate.cpp
index 1e9cb42f38..87b8add2a3 100644
--- a/esphome/components/haier/hon_climate.cpp
+++ b/esphome/components/haier/hon_climate.cpp
@@ -85,7 +85,7 @@ void HonClimate::set_horizontal_airflow(hon_protocol::HorizontalSwingMode direct
   this->force_send_control_ = true;
 }
 
-std::string HonClimate::get_cleaning_status_text() const {
+const char *HonClimate::get_cleaning_status_text() const {
   switch (this->cleaning_status_) {
     case CleaningState::SELF_CLEAN:
       return "Self clean";
@@ -134,29 +134,22 @@ haier_protocol::HandlerError HonClimate::get_device_version_answer_handler_(haie
     }
     // All OK
     hon_protocol::DeviceVersionAnswer *answr = (hon_protocol::DeviceVersionAnswer *) data;
-    char tmp[9];
-    tmp[8] = 0;
-    strncpy(tmp, answr->protocol_version, 8);
-    this->hvac_hardware_info_ = HardwareInfo();
-    this->hvac_hardware_info_.value().protocol_version_ = std::string(tmp);
-    strncpy(tmp, answr->software_version, 8);
-    this->hvac_hardware_info_.value().software_version_ = std::string(tmp);
-    strncpy(tmp, answr->hardware_version, 8);
-    this->hvac_hardware_info_.value().hardware_version_ = std::string(tmp);
-    strncpy(tmp, answr->device_name, 8);
-    this->hvac_hardware_info_.value().device_name_ = std::string(tmp);
+    HardwareInfo info{};  // zero-init guarantees null-termination
+    strncpy(info.protocol_version_, answr->protocol_version, HARDWARE_INFO_STR_SIZE - 1);
+    strncpy(info.software_version_, answr->software_version, HARDWARE_INFO_STR_SIZE - 1);
+    strncpy(info.hardware_version_, answr->hardware_version, HARDWARE_INFO_STR_SIZE - 1);
+    strncpy(info.device_name_, answr->device_name, HARDWARE_INFO_STR_SIZE - 1);
+    info.functions_[0] = (answr->functions[1] & 0x01) != 0;  // interactive mode support
+    info.functions_[1] = (answr->functions[1] & 0x02) != 0;  // controller-device mode support
+    info.functions_[2] = (answr->functions[1] & 0x04) != 0;  // crc support
+    info.functions_[3] = (answr->functions[1] & 0x08) != 0;  // multiple AC support
+    info.functions_[4] = (answr->functions[1] & 0x20) != 0;  // roles support
+    this->use_crc_ = info.functions_[2];
 #ifdef USE_TEXT_SENSOR
-    this->update_sub_text_sensor_(SubTextSensorType::APPLIANCE_NAME, this->hvac_hardware_info_.value().device_name_);
-    this->update_sub_text_sensor_(SubTextSensorType::PROTOCOL_VERSION,
-                                  this->hvac_hardware_info_.value().protocol_version_);
+    this->update_sub_text_sensor_(SubTextSensorType::APPLIANCE_NAME, info.device_name_);
+    this->update_sub_text_sensor_(SubTextSensorType::PROTOCOL_VERSION, info.protocol_version_);
 #endif
-    this->hvac_hardware_info_.value().functions_[0] = (answr->functions[1] & 0x01) != 0;  // interactive mode support
-    this->hvac_hardware_info_.value().functions_[1] =
-        (answr->functions[1] & 0x02) != 0;  // controller-device mode support
-    this->hvac_hardware_info_.value().functions_[2] = (answr->functions[1] & 0x04) != 0;  // crc support
-    this->hvac_hardware_info_.value().functions_[3] = (answr->functions[1] & 0x08) != 0;  // multiple AC support
-    this->hvac_hardware_info_.value().functions_[4] = (answr->functions[1] & 0x20) != 0;  // roles support
-    this->use_crc_ = this->hvac_hardware_info_.value().functions_[2];
+    this->hvac_hardware_info_ = info;
     this->set_phase(ProtocolPhases::SENDING_INIT_2);
     return result;
   } else {
@@ -347,10 +340,9 @@ void HonClimate::dump_config() {
                   "  Device software version: %s\n"
                   "  Device hardware version: %s\n"
                   "  Device name: %s",
-                  this->hvac_hardware_info_.value().protocol_version_.c_str(),
-                  this->hvac_hardware_info_.value().software_version_.c_str(),
-                  this->hvac_hardware_info_.value().hardware_version_.c_str(),
-                  this->hvac_hardware_info_.value().device_name_.c_str());
+                  this->hvac_hardware_info_.value().protocol_version_,
+                  this->hvac_hardware_info_.value().software_version_,
+                  this->hvac_hardware_info_.value().hardware_version_, this->hvac_hardware_info_.value().device_name_);
     ESP_LOGCONFIG(TAG, "  Device features:%s%s%s%s%s",
                   (this->hvac_hardware_info_.value().functions_[0] ? " interactive" : ""),
                   (this->hvac_hardware_info_.value().functions_[1] ? " controller-device" : ""),
@@ -460,7 +452,7 @@ void HonClimate::process_phase(std::chrono::steady_clock::time_point now) {
       if (this->action_request_.has_value()) {
         if (this->action_request_.value().message.has_value()) {
           this->send_message_(this->action_request_.value().message.value(), this->use_crc_);
-          this->action_request_.value().message.reset();
+          this->action_request_.value().message.reset();  // NOLINT(bugprone-unchecked-optional-access)
         } else {
           // Message already sent, reseting request and return to idle
           this->action_request_.reset();
@@ -796,7 +788,7 @@ void HonClimate::set_sub_text_sensor(SubTextSensorType type, text_sensor::TextSe
   }
 }
 
-void HonClimate::update_sub_text_sensor_(SubTextSensorType type, const std::string &value) {
+void HonClimate::update_sub_text_sensor_(SubTextSensorType type, const char *value) {
   size_t index = (size_t) type;
   if (this->sub_text_sensors_[index] != nullptr)
     this->sub_text_sensors_[index]->publish_state(value);
diff --git a/esphome/components/haier/hon_climate.h b/esphome/components/haier/hon_climate.h
index 7a87f27b66..a0bcdfb548 100644
--- a/esphome/components/haier/hon_climate.h
+++ b/esphome/components/haier/hon_climate.h
@@ -90,7 +90,7 @@ class HonClimate : public HaierClimateBase {
   void set_sub_text_sensor(SubTextSensorType type, text_sensor::TextSensor *sens);
 
  protected:
-  void update_sub_text_sensor_(SubTextSensorType type, const std::string &value);
+  void update_sub_text_sensor_(SubTextSensorType type, const char *value);
   text_sensor::TextSensor *sub_text_sensors_[(size_t) SubTextSensorType::SUB_TEXT_SENSOR_TYPE_COUNT]{nullptr};
 #endif
 #ifdef USE_SWITCH
@@ -116,7 +116,7 @@ class HonClimate : public HaierClimateBase {
   void set_vertical_airflow(hon_protocol::VerticalSwingMode direction);
   esphome::optional<hon_protocol::HorizontalSwingMode> get_horizontal_airflow() const;
   void set_horizontal_airflow(hon_protocol::HorizontalSwingMode direction);
-  std::string get_cleaning_status_text() const;
+  const char *get_cleaning_status_text() const;
   CleaningState get_cleaning_status() const;
   void start_self_cleaning();
   void start_steri_cleaning();
@@ -166,11 +166,12 @@ class HonClimate : public HaierClimateBase {
   void fill_control_messages_queue_();
   void clear_control_messages_queue_();
 
+  static constexpr size_t HARDWARE_INFO_STR_SIZE = 9;
   struct HardwareInfo {
-    std::string protocol_version_;
-    std::string software_version_;
-    std::string hardware_version_;
-    std::string device_name_;
+    char protocol_version_[HARDWARE_INFO_STR_SIZE];
+    char software_version_[HARDWARE_INFO_STR_SIZE];
+    char hardware_version_[HARDWARE_INFO_STR_SIZE];
+    char device_name_[HARDWARE_INFO_STR_SIZE];
     bool functions_[5];
   };
 
diff --git a/esphome/components/haier/smartair2_climate.cpp b/esphome/components/haier/smartair2_climate.cpp
index 2be5d13050..752f4d4f1c 100644
--- a/esphome/components/haier/smartair2_climate.cpp
+++ b/esphome/components/haier/smartair2_climate.cpp
@@ -191,7 +191,7 @@ void Smartair2Climate::process_phase(std::chrono::steady_clock::time_point now)
       if (this->action_request_.has_value()) {
         if (this->action_request_.value().message.has_value()) {
           this->send_message_(this->action_request_.value().message.value(), this->use_crc_);
-          this->action_request_.value().message.reset();
+          this->action_request_.value().message.reset();  // NOLINT(bugprone-unchecked-optional-access)
         } else {
           // Message already sent, reseting request and return to idle
           this->action_request_.reset();
@@ -210,8 +210,9 @@ void Smartair2Climate::process_phase(std::chrono::steady_clock::time_point now)
 #ifdef USE_WIFI
       else if (this->send_wifi_signal_ &&
                (std::chrono::duration_cast<std::chrono::milliseconds>(now - this->last_signal_request_).count() >
-                SIGNAL_LEVEL_UPDATE_INTERVAL_MS))
+                SIGNAL_LEVEL_UPDATE_INTERVAL_MS)) {
         this->set_phase(ProtocolPhases::SENDING_UPDATE_SIGNAL_REQUEST);
+      }
 #endif
     } break;
     default:
diff --git a/esphome/components/host/core.cpp b/esphome/components/host/core.cpp
index b067ebbf6e..9123975884 100644
--- a/esphome/components/host/core.cpp
+++ b/esphome/components/host/core.cpp
@@ -1,74 +1,16 @@
 #ifdef USE_HOST
 
 #include "esphome/core/application.h"
-#include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
 #include "preferences.h"
 
 #include <csignal>
-#include <sched.h>
-#include <time.h>
-#include <cstdlib>
 
 namespace {
 volatile sig_atomic_t s_signal_received = 0;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 void signal_handler(int signal) { s_signal_received = signal; }
 }  // namespace
 
-namespace esphome {
-
-void HOT yield() { ::sched_yield(); }
-uint32_t IRAM_ATTR HOT millis() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint32_t>(spec.tv_sec * 1000ULL + spec.tv_nsec / 1000000);
-}
-uint64_t millis_64() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint64_t>(spec.tv_sec) * 1000ULL + static_cast<uint64_t>(spec.tv_nsec) / 1000000ULL;
-}
-void HOT delay(uint32_t ms) {
-  struct timespec ts;
-  ts.tv_sec = ms / 1000;
-  ts.tv_nsec = (ms % 1000) * 1000000;
-  int res;
-  do {
-    res = nanosleep(&ts, &ts);
-  } while (res != 0 && errno == EINTR);
-}
-uint32_t IRAM_ATTR HOT micros() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  return static_cast<uint32_t>(spec.tv_sec * 1000000ULL + spec.tv_nsec / 1000);
-}
-void IRAM_ATTR HOT delayMicroseconds(uint32_t us) {
-  struct timespec ts;
-  ts.tv_sec = us / 1000000U;
-  ts.tv_nsec = (us % 1000000U) * 1000U;
-  int res;
-  do {
-    res = nanosleep(&ts, &ts);
-  } while (res != 0 && errno == EINTR);
-}
-void arch_restart() { exit(0); }
-void arch_init() {
-  // pass
-}
-void HOT arch_feed_wdt() {
-  // pass
-}
-
-uint32_t arch_get_cpu_cycle_count() {
-  struct timespec spec;
-  clock_gettime(CLOCK_MONOTONIC, &spec);
-  time_t seconds = spec.tv_sec;
-  uint32_t us = spec.tv_nsec;
-  return ((uint32_t) seconds) * 1000000000U + us;
-}
-uint32_t arch_get_cpu_freq_hz() { return 1000000000U; }
-
-}  // namespace esphome
+// HAL functions live in hal.cpp.
 
 void setup();
 void loop();
diff --git a/esphome/components/host/hal.cpp b/esphome/components/host/hal.cpp
new file mode 100644
index 0000000000..c7fef8d2e8
--- /dev/null
+++ b/esphome/components/host/hal.cpp
@@ -0,0 +1,65 @@
+#ifdef USE_HOST
+
+#include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
+
+#include <time.h>
+#include <cerrno>
+#include <cstdlib>
+
+// Empty host namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// host component's API.
+namespace esphome::host {}  // namespace esphome::host
+
+namespace esphome {
+
+// yield(), arch_init(), arch_feed_wdt(), arch_get_cpu_freq_hz() inlined in
+// components/host/hal.h.
+
+uint32_t IRAM_ATTR HOT millis() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint32_t>(spec.tv_sec * 1000ULL + spec.tv_nsec / 1000000);
+}
+uint64_t millis_64() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint64_t>(spec.tv_sec) * 1000ULL + static_cast<uint64_t>(spec.tv_nsec) / 1000000ULL;
+}
+void HOT delay(uint32_t ms) {
+  struct timespec ts;
+  ts.tv_sec = ms / 1000;
+  ts.tv_nsec = (ms % 1000) * 1000000;
+  int res;
+  do {
+    res = nanosleep(&ts, &ts);
+  } while (res != 0 && errno == EINTR);
+}
+uint32_t IRAM_ATTR HOT micros() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  return static_cast<uint32_t>(spec.tv_sec * 1000000ULL + spec.tv_nsec / 1000);
+}
+void IRAM_ATTR HOT delayMicroseconds(uint32_t us) {
+  struct timespec ts;
+  ts.tv_sec = us / 1000000U;
+  ts.tv_nsec = (us % 1000000U) * 1000U;
+  int res;
+  do {
+    res = nanosleep(&ts, &ts);
+  } while (res != 0 && errno == EINTR);
+}
+void arch_restart() { exit(0); }
+
+uint32_t arch_get_cpu_cycle_count() {
+  struct timespec spec;
+  clock_gettime(CLOCK_MONOTONIC, &spec);
+  time_t seconds = spec.tv_sec;
+  uint32_t ns = static_cast<uint32_t>(spec.tv_nsec);
+  return static_cast<uint32_t>(seconds) * 1000000000U + ns;
+}
+
+}  // namespace esphome
+
+#endif  // USE_HOST
diff --git a/esphome/components/host/hal.h b/esphome/components/host/hal.h
new file mode 100644
index 0000000000..12abf6684d
--- /dev/null
+++ b/esphome/components/host/hal.h
@@ -0,0 +1,34 @@
+#pragma once
+
+#ifdef USE_HOST
+
+#include <cstdint>
+#include <sched.h>
+
+#define IRAM_ATTR
+#define PROGMEM
+
+namespace esphome::host {}
+
+namespace esphome {
+
+/// Returns true when executing inside an interrupt handler.
+/// Host has no ISR concept.
+__attribute__((always_inline)) inline bool in_isr_context() { return false; }
+
+__attribute__((always_inline)) inline void yield() { ::sched_yield(); }
+
+void delay(uint32_t ms);
+uint32_t micros();
+uint32_t millis();
+uint64_t millis_64();
+void delayMicroseconds(uint32_t us);  // NOLINT(readability-identifier-naming)
+uint32_t arch_get_cpu_cycle_count();
+
+__attribute__((always_inline)) inline void arch_init() {}
+__attribute__((always_inline)) inline void arch_feed_wdt() {}
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_freq_hz() { return 1000000000U; }
+
+}  // namespace esphome
+
+#endif  // USE_HOST
diff --git a/esphome/components/http_request/http_request.h b/esphome/components/http_request/http_request.h
index f37bf77633..2477e26bc1 100644
--- a/esphome/components/http_request/http_request.h
+++ b/esphome/components/http_request/http_request.h
@@ -462,7 +462,7 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
     this->request_headers_.push_back({key, value});
   }
 
-  void add_collect_header(const char *value) { this->lower_case_collect_headers_.push_back(value); }
+  void add_collect_header(const char *value) { this->lower_case_collect_headers_.emplace_back(value); }
 
   void init_json(size_t count) { this->json_.init(count); }
   void add_json(const char *key, TemplatableValue<std::string, Ts...> value) { this->json_.push_back({key, value}); }
diff --git a/esphome/components/http_request/http_request_arduino.cpp b/esphome/components/http_request/http_request_arduino.cpp
index 05f9db1c06..217ad0064d 100644
--- a/esphome/components/http_request/http_request_arduino.cpp
+++ b/esphome/components/http_request/http_request_arduino.cpp
@@ -243,7 +243,7 @@ int HttpContainerArduino::read(uint8_t *buf, size_t max_len) {
   // Non-chunked path
   int available_data = stream_ptr->available();
   size_t remaining = (this->content_length > 0) ? (this->content_length - this->bytes_read_) : max_len;
-  int bufsize = std::min(max_len, std::min(remaining, (size_t) available_data));
+  int bufsize = std::min({max_len, remaining, (size_t) available_data});
 
   if (bufsize == 0) {
     this->duration_ms += (millis() - start);
diff --git a/esphome/components/i2c/i2c_bus_zephyr.h b/esphome/components/i2c/i2c_bus_zephyr.h
index 49cac5b992..3c4aa9ed1d 100644
--- a/esphome/components/i2c/i2c_bus_zephyr.h
+++ b/esphome/components/i2c/i2c_bus_zephyr.h
@@ -5,7 +5,7 @@
 #include "i2c_bus.h"
 #include "esphome/core/component.h"
 
-struct device;
+struct device;  // NOLINT(readability-identifier-naming) - forward decl of Zephyr's device type
 
 namespace esphome::i2c {
 
diff --git a/esphome/components/image/__init__.py b/esphome/components/image/__init__.py
index 8375ab91d3..365554f7d2 100644
--- a/esphome/components/image/__init__.py
+++ b/esphome/components/image/__init__.py
@@ -744,21 +744,28 @@ async def write_image(config, all_frames=False):
         if frame_count <= 1:
             _LOGGER.warning("Image file %s has no animation frames", path)
 
-    total_rows = height * frame_count
-    encoder = IMAGE_TYPE[type](width, total_rows, transparency, dither, invert_alpha)
-    if byte_order := config.get(CONF_BYTE_ORDER):
-        # Check for valid type has already been done in validate_settings
-        encoder.set_big_endian(byte_order == "BIG_ENDIAN")
+    # Encode each frame with its own encoder and concatenate. This keeps every
+    # frame self-contained on disk (e.g. RGB565+alpha emits [RGB plane | alpha plane]
+    # per frame) so animation frame stepping in image.cpp / animation.cpp stays
+    # correct without needing to know the total frame count.
+    byte_order = config.get(CONF_BYTE_ORDER)
+    combined_data: list[int] = []
+    encoder: ImageEncoder | None = None
     for frame_index in range(frame_count):
         image.seek(frame_index)
+        encoder = IMAGE_TYPE[type](width, height, transparency, dither, invert_alpha)
+        if byte_order is not None:
+            # Check for valid type has already been done in validate_settings
+            encoder.set_big_endian(byte_order == "BIG_ENDIAN")
         pixels = encoder.convert(image.resize((width, height)), path).getdata()
         for row in range(height):
             for col in range(width):
                 encoder.encode(pixels[row * width + col])
             encoder.end_row()
-    encoder.end_image()
+        encoder.end_image()
+        combined_data.extend(encoder.data)
 
-    rhs = [HexInt(x) for x in encoder.data]
+    rhs = [HexInt(x) for x in combined_data]
     prog_arr = cg.progmem_array(config[CONF_RAW_DATA_ID], rhs)
     image_type = get_image_type_enum(type)
     trans_value = get_transparency_enum(encoder.transparency)
diff --git a/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp b/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
index 94c22ae84d..c53d8e5029 100644
--- a/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
+++ b/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
@@ -41,12 +41,12 @@ bool InkbirdIbstH1Mini::parse_device(const esp32_ble_tracker::ESPBTDevice &devic
     ESP_LOGVV(TAG, "parse_device(): service_data is expected to be empty");
     return false;
   }
-  auto mnf_datas = device.get_manufacturer_datas();
+  const auto &mnf_datas = device.get_manufacturer_datas();
   if (mnf_datas.size() != 1) {
     ESP_LOGVV(TAG, "parse_device(): manufacturer_datas is expected to have a single element");
     return false;
   }
-  auto mnf_data = mnf_datas[0];
+  const auto &mnf_data = mnf_datas[0];
   if (mnf_data.uuid.get_uuid().len != ESP_UUID_LEN_16) {
     ESP_LOGVV(TAG, "parse_device(): manufacturer data element is expected to have uuid of length 16");
     return false;
diff --git a/esphome/components/json/json_util.cpp b/esphome/components/json/json_util.cpp
index edcd23f922..ec1490be1f 100644
--- a/esphome/components/json/json_util.cpp
+++ b/esphome/components/json/json_util.cpp
@@ -39,7 +39,8 @@ bool parse_json(const uint8_t *data, size_t len, const json_parse_t &f) {
 }
 
 JsonDocument parse_json(const uint8_t *data, size_t len) {
-  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks,clang-analyzer-core.StackAddressEscape) false positives with
+  // ArduinoJson
   if (data == nullptr || len == 0) {
     ESP_LOGE(TAG, "No data to parse");
     return JsonObject();  // return unbound object
@@ -63,7 +64,7 @@ JsonDocument parse_json(const uint8_t *data, size_t len) {
   }
   ESP_LOGE(TAG, "Parse error: %s", err.c_str());
   return JsonObject();  // return unbound object
-  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks,clang-analyzer-core.StackAddressEscape)
 }
 
 SerializationBuffer<> JsonBuilder::serialize() {
diff --git a/esphome/components/kamstrup_kmp/kamstrup_kmp.cpp b/esphome/components/kamstrup_kmp/kamstrup_kmp.cpp
index 9f2557243c..9bebd4cd56 100644
--- a/esphome/components/kamstrup_kmp/kamstrup_kmp.cpp
+++ b/esphome/components/kamstrup_kmp/kamstrup_kmp.cpp
@@ -139,12 +139,12 @@ void KamstrupKMPComponent::clear_uart_rx_buffer_() {
 
 void KamstrupKMPComponent::read_command_(uint16_t command) {
   uint8_t buffer[20] = {0};
-  int buffer_len = 0;
+  size_t buffer_len = 0;
   int data;
   int timeout = 250;  // ms
 
   // Read the data from the UART
-  while (timeout > 0 && buffer_len < static_cast<int>(sizeof(buffer))) {
+  while (timeout > 0 && buffer_len < sizeof(buffer)) {
     if (this->available()) {
       data = this->read();
       if (data > -1) {
@@ -183,7 +183,7 @@ void KamstrupKMPComponent::read_command_(uint16_t command) {
   // Decode
   uint8_t msg[20] = {0};
   int msg_len = 0;
-  for (int i = 1; i < buffer_len - 1; i++) {
+  for (size_t i = 1; i < buffer_len - 1; i++) {
     if (buffer[i] == 0x1B) {
       msg[msg_len++] = buffer[i + 1] ^ 0xFF;
       i++;
diff --git a/esphome/components/libretiny/__init__.py b/esphome/components/libretiny/__init__.py
index 40b8c8dc6c..40fb773784 100644
--- a/esphome/components/libretiny/__init__.py
+++ b/esphome/components/libretiny/__init__.py
@@ -37,6 +37,7 @@ from .const import (
     CONF_UART_PORT,
     FAMILIES,
     FAMILY_BK7231N,
+    FAMILY_BK7238,
     FAMILY_COMPONENT,
     FAMILY_FRIENDLY,
     FAMILY_RTL8710B,
@@ -56,19 +57,22 @@ CODEOWNERS = ["@kuba2k2"]
 AUTO_LOAD = ["preferences"]
 IS_TARGET_PLATFORM = True
 
-# BK7231N SDK options to disable unused features.
+# BLE 5.x BK SDK options to disable unused features.
 # Disabling BLE saves ~21KB RAM and ~200KB Flash because BLE init code is
 # called unconditionally by the SDK. ESPHome doesn't use BLE on LibreTiny.
 #
-# This only works on BK7231N (BLE 5.x). Other BK72XX chips using BLE 4.2
-# (BK7231T, BK7231Q, BK7251; BK7252 boards use the BK7251 family) have a bug
-# where the BLE library still links and references undefined symbols when
-# CFG_SUPPORT_BLE=0.
+# This only works on BLE 5.x BK chips (BK7231N, BK7238). Other BK72XX chips
+# using BLE 4.2 (BK7231T, BK7231Q, BK7251; BK7252 boards use the BK7251 family)
+# have a bug where the BLE library still links and references undefined symbols
+# when CFG_SUPPORT_BLE=0.
+#
+# On BK7238 the SDK also hangs at WiFi STA enable when BLE init runs, so
+# disabling it is required for reliable boot, not just an optimization.
 #
 # Other options like CFG_TX_EVM_TEST, CFG_RX_SENSITIVITY_TEST, CFG_SUPPORT_BKREG,
 # CFG_SUPPORT_OTA_HTTP, and CFG_USE_SPI_SLAVE were evaluated but provide no  # NOLINT
 # measurable benefit - the linker already strips unreferenced code via -gc-sections.
-_BK7231N_SYS_CONFIG_OPTIONS = [
+_BLE5_BK_SYS_CONFIG_OPTIONS = [
     "CFG_SUPPORT_BLE=0",
 ]
 
@@ -152,6 +156,18 @@ def only_on_family(*, supported=None, unsupported=None):
 
 
 def get_download_types(storage_json: StorageJSON = None):
+    """Binary-download entries for a built LibreTiny firmware.
+
+    Used by:
+    - esphome.dashboard (legacy "Download .bin" button)
+    - device-builder (esphome/device-builder) — same dispatch via
+      ``importlib.import_module(f"esphome.components.{platform}")``
+      then ``module.get_download_types(storage)``. The contract is
+      "returns ``list[dict]`` with at least ``title`` /
+      ``description`` / ``file`` / ``download`` keys"; please keep
+      the shape stable so the new dashboard's download panel
+      doesn't have to special-case per-platform schemas.
+    """
     types = [
         {
             "title": "UF2 package (recommended)",
@@ -549,9 +565,9 @@ async def component_to_code(config):
         cg.add_platformio_option("custom_fw_version", __version__)
 
     # Apply chip-specific SDK options to save RAM/Flash
-    if config[CONF_FAMILY] == FAMILY_BK7231N:
+    if config[CONF_FAMILY] in (FAMILY_BK7231N, FAMILY_BK7238):
         cg.add_platformio_option(
-            "custom_options.sys_config#h", _BK7231N_SYS_CONFIG_OPTIONS
+            "custom_options.sys_config#h", _BLE5_BK_SYS_CONFIG_OPTIONS
         )
 
     # Tune lwIP for ESPHome's actual needs.
diff --git a/esphome/components/libretiny/const.py b/esphome/components/libretiny/const.py
index 5de4a164b5..0119a0db3f 100644
--- a/esphome/components/libretiny/const.py
+++ b/esphome/components/libretiny/const.py
@@ -54,6 +54,14 @@ COMPONENT_LN882X = "ln882x"
 COMPONENT_RTL87XX = "rtl87xx"
 # COMPONENTS - end
 
+# Note for ``generate_components.py`` maintainers: the
+# ``FAMILY_COMPONENT`` map below is also consumed externally —
+# device-builder (esphome/device-builder) derives the set of
+# ``target_platform`` values that should route to the ``libretiny``
+# component for the dashboard's ``get_download_types`` lookup from
+# ``FAMILY_COMPONENT.values()``. New chip families added by the
+# generator are picked up automatically; please don't repurpose
+# the public ``FAMILY_COMPONENT`` name without coordinating.
 # FAMILIES - auto-generated! Do not modify this block.
 FAMILY_BK7231N = "BK7231N"
 FAMILY_BK7231Q = "BK7231Q"
diff --git a/esphome/components/libretiny/core.cpp b/esphome/components/libretiny/core.cpp
index ca46bcb899..8686a41e64 100644
--- a/esphome/components/libretiny/core.cpp
+++ b/esphome/components/libretiny/core.cpp
@@ -1,81 +1,6 @@
 #ifdef USE_LIBRETINY
 
-#include "core.h"
-#include "esphome/core/defines.h"
-#include "esphome/core/hal.h"
-#include "esphome/core/time_64.h"
-#include "esphome/core/helpers.h"
-#include "preferences.h"
-
-#include <FreeRTOS.h>
-#include <task.h>
-
-void setup();
-void loop();
-
-namespace esphome {
-
-void HOT yield() { ::yield(); }
-// Inline the tick read so esphome::millis() matches MillisInternal::get()'s fast
-// path instead of going through the Arduino core's out-of-line ::millis() wrapper.
-//
-// RTL87xx / LN882x (1 kHz): xTaskGetTickCount() is already ms. IRAM_ATTR + ISR
-// dispatch are needed because ISR handlers (e.g. rotary_encoder) call millis().
-//
-// BK72xx (500 Hz): ticks * portTICK_PERIOD_MS (== 2). IRAM_ATTR and ISR dispatch
-// are both unnecessary — the SDK masks FIQ + IRQ during flash writes (see hal.h),
-// so no ISR runs while flash is stalled.
-#if defined(USE_RTL87XX) || defined(USE_LN882X)
-uint32_t IRAM_ATTR HOT millis() {
-  static_assert(configTICK_RATE_HZ == 1000, "millis() fast path requires 1 kHz FreeRTOS tick");
-  return in_isr_context() ? xTaskGetTickCountFromISR() : xTaskGetTickCount();
-}
-#elif defined(USE_BK72XX)
-uint32_t HOT millis() {
-  static_assert(configTICK_RATE_HZ == 500, "BK72xx millis() fast path assumes 500 Hz FreeRTOS tick");
-  return xTaskGetTickCount() * portTICK_PERIOD_MS;
-}
-#else
-uint32_t IRAM_ATTR HOT millis() { return ::millis(); }
-#endif
-uint64_t millis_64() { return Millis64Impl::compute(millis()); }
-uint32_t IRAM_ATTR HOT micros() { return ::micros(); }
-void HOT delay(uint32_t ms) { ::delay(ms); }
-void IRAM_ATTR HOT delayMicroseconds(uint32_t us) { ::delayMicroseconds(us); }
-
-void arch_init() {
-  libretiny::setup_preferences();
-  lt_wdt_enable(10000L);
-#ifdef USE_BK72XX
-  // BK72xx SDK creates the main Arduino task at priority 3, which is lower than
-  // all WiFi (4-5), LwIP (4), and TCP/IP (7) tasks. This causes ~100ms loop
-  // stalls whenever WiFi background processing runs, because the main task
-  // cannot resume until every higher-priority task finishes.
-  //
-  // By contrast, RTL87xx creates the main task at osPriorityRealtime (highest).
-  //
-  // Raise to priority 6: above WiFi/LwIP tasks (4-5) so they don't preempt the
-  // main loop, but below the TCP/IP thread (7) so packet processing keeps priority.
-  // This is safe because ESPHome yields voluntarily via wakeable_delay() and
-  // the Arduino mainTask yield() after each loop() iteration.
-  static constexpr UBaseType_t MAIN_TASK_PRIORITY = 6;
-  static_assert(MAIN_TASK_PRIORITY < configMAX_PRIORITIES, "MAIN_TASK_PRIORITY must be less than configMAX_PRIORITIES");
-  vTaskPrioritySet(nullptr, MAIN_TASK_PRIORITY);
-#endif
-#if LT_GPIO_RECOVER
-  lt_gpio_recover();
-#endif
-}
-
-void arch_restart() {
-  lt_reboot();
-  while (1) {
-  }
-}
-void HOT arch_feed_wdt() { lt_wdt_feed(); }
-uint32_t arch_get_cpu_cycle_count() { return lt_cpu_get_cycle_count(); }
-uint32_t arch_get_cpu_freq_hz() { return lt_cpu_get_freq(); }
-
-}  // namespace esphome
+// HAL functions live in hal.cpp. core.cpp is intentionally empty for
+// libretiny — there is no extra component bootstrap to keep here.
 
 #endif  // USE_LIBRETINY
diff --git a/esphome/components/libretiny/hal.cpp b/esphome/components/libretiny/hal.cpp
new file mode 100644
index 0000000000..67e902024d
--- /dev/null
+++ b/esphome/components/libretiny/hal.cpp
@@ -0,0 +1,53 @@
+#ifdef USE_LIBRETINY
+
+#include "core.h"
+#include "esphome/core/hal.h"
+#include "preferences.h"
+
+#include <FreeRTOS.h>
+#include <task.h>
+
+// Empty libretiny namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// libretiny component's API.
+namespace esphome::libretiny {}  // namespace esphome::libretiny
+
+namespace esphome {
+
+// yield(), delay(), micros(), millis(), millis_64(), delayMicroseconds(),
+// arch_feed_wdt(), arch_get_cpu_cycle_count(), arch_get_cpu_freq_hz()
+// inlined in components/libretiny/hal.h.
+
+void arch_init() {
+  libretiny::setup_preferences();
+  lt_wdt_enable(10000L);
+#ifdef USE_BK72XX
+  // BK72xx SDK creates the main Arduino task at priority 3, which is lower than
+  // all WiFi (4-5), LwIP (4), and TCP/IP (7) tasks. This causes ~100ms loop
+  // stalls whenever WiFi background processing runs, because the main task
+  // cannot resume until every higher-priority task finishes.
+  //
+  // By contrast, RTL87xx creates the main task at osPriorityRealtime (highest).
+  //
+  // Raise to priority 6: above WiFi/LwIP tasks (4-5) so they don't preempt the
+  // main loop, but below the TCP/IP thread (7) so packet processing keeps priority.
+  // This is safe because ESPHome yields voluntarily via wakeable_delay() and
+  // the Arduino mainTask yield() after each loop() iteration.
+  static constexpr UBaseType_t MAIN_TASK_PRIORITY = 6;
+  static_assert(MAIN_TASK_PRIORITY < configMAX_PRIORITIES, "MAIN_TASK_PRIORITY must be less than configMAX_PRIORITIES");
+  vTaskPrioritySet(nullptr, MAIN_TASK_PRIORITY);
+#endif
+#if LT_GPIO_RECOVER
+  lt_gpio_recover();
+#endif
+}
+
+void arch_restart() {
+  lt_reboot();
+  while (1) {
+  }
+}
+
+}  // namespace esphome
+
+#endif  // USE_LIBRETINY
diff --git a/esphome/components/libretiny/hal.h b/esphome/components/libretiny/hal.h
new file mode 100644
index 0000000000..9c512504b7
--- /dev/null
+++ b/esphome/components/libretiny/hal.h
@@ -0,0 +1,111 @@
+#pragma once
+
+#ifdef USE_LIBRETINY
+
+#include <cstdint>
+
+// For the inline millis() fast paths (xTaskGetTickCount, portTICK_PERIOD_MS).
+#include <FreeRTOS.h>
+#include <task.h>
+
+#include "esphome/core/time_64.h"
+
+// IRAM_ATTR places a function in executable RAM so it is callable from an
+// ISR even while flash is busy (XIP stall, OTA, logger flash write).
+// Each family uses a section its stock linker already routes to RAM:
+// RTL8710B → .image2.ram.text, RTL8720C → .sram.text. LN882H is the
+// exception: its stock linker has no matching glob, so patch_linker.py
+// injects KEEP(*(.sram.text*)) into .flash_copysection at pre-link.
+//
+// BK72xx (all variants) are left as a no-op: their SDK wraps flash
+// operations in GLOBAL_INT_DISABLE() which masks FIQ + IRQ at the CPU for
+// the duration of every write, so no ISR fires while flash is stalled and
+// the race IRAM_ATTR guards against cannot occur. The trade-off is that
+// interrupts are delayed (not dropped) by up to ~20 ms during a sector
+// erase, but that is an SDK-level choice and cannot be changed from this
+// layer.
+#if defined(USE_BK72XX)
+#define IRAM_ATTR
+#elif defined(USE_LIBRETINY_VARIANT_RTL8710B)
+// Stock linker consumes *(.image2.ram.text*) into .ram_image2.text (> BD_RAM).
+#define IRAM_ATTR __attribute__((noinline, section(".image2.ram.text")))
+#else
+// RTL8720C: stock linker consumes *(.sram.text*) into .ram.code_text.
+// LN882H: patch_linker.py.script injects *(.sram.text*) into
+// .flash_copysection (> RAM0 AT> FLASH).
+#define IRAM_ATTR __attribute__((noinline, section(".sram.text")))
+#endif
+#define PROGMEM
+
+#ifdef USE_BK72XX
+// Declared in the Beken FreeRTOS port (portmacro.h) and built in ARM mode so
+// it is callable from Thumb code via interworking. The MRS CPSR instruction
+// is ARM-only and user code here may be built in Thumb, so in_isr_context()
+// defers to this port helper on BK72xx instead of reading CPSR inline.
+extern "C" uint32_t platform_is_in_interrupt_context(void);
+#endif
+
+// Forward decls from Arduino's <Arduino.h> for the inline wrappers below.
+// NOLINTBEGIN(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+extern "C" void yield(void);
+extern "C" void delay(unsigned long ms);
+extern "C" unsigned long micros(void);
+extern "C" unsigned long millis(void);
+extern "C" void delayMicroseconds(unsigned int us);
+// NOLINTEND(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+
+// Forward decls from libretiny's <lt_api.h> family for the inline arch_*
+// wrappers below. Pulling the full header would drag in the rest of the
+// LibreTiny C API.
+extern "C" void lt_wdt_feed(void);
+extern "C" uint32_t lt_cpu_get_cycle_count(void);
+extern "C" uint32_t lt_cpu_get_freq(void);
+
+namespace esphome::libretiny {}
+
+namespace esphome {
+
+/// Returns true when executing inside an interrupt handler.
+__attribute__((always_inline)) inline bool in_isr_context() {
+#if defined(USE_BK72XX)
+  // BK72xx is ARM968E-S (ARM9); see extern declaration above.
+  return platform_is_in_interrupt_context() != 0;
+#else
+  // Cortex-M (AmebaZ, AmebaZ2, LN882H). IPSR is the active exception number;
+  // non-zero means we're in a handler.
+  uint32_t ipsr;
+  __asm__ volatile("mrs %0, ipsr" : "=r"(ipsr));
+  return ipsr != 0;
+#endif
+}
+
+__attribute__((always_inline)) inline void yield() { ::yield(); }
+__attribute__((always_inline)) inline void delay(uint32_t ms) { ::delay(ms); }
+__attribute__((always_inline)) inline uint32_t micros() { return static_cast<uint32_t>(::micros()); }
+
+// Per-variant millis() fast path — matches MillisInternal::get().
+#if defined(USE_RTL87XX) || defined(USE_LN882X)
+static_assert(configTICK_RATE_HZ == 1000, "millis() fast path requires 1 kHz FreeRTOS tick");
+__attribute__((always_inline)) inline uint32_t millis() {
+  // xTaskGetTickCountFromISR is mandatory in interrupt context per the FreeRTOS API contract.
+  return in_isr_context() ? xTaskGetTickCountFromISR() : xTaskGetTickCount();
+}
+#elif defined(USE_BK72XX)
+static_assert(configTICK_RATE_HZ == 500, "BK72xx millis() fast path assumes 500 Hz FreeRTOS tick");
+__attribute__((always_inline)) inline uint32_t millis() { return xTaskGetTickCount() * portTICK_PERIOD_MS; }
+#else
+__attribute__((always_inline)) inline uint32_t millis() { return static_cast<uint32_t>(::millis()); }
+#endif
+__attribute__((always_inline)) inline uint64_t millis_64() { return Millis64Impl::compute(millis()); }
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { ::delayMicroseconds(us); }
+__attribute__((hot, always_inline)) inline void arch_feed_wdt() { lt_wdt_feed(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() { return lt_cpu_get_cycle_count(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_freq_hz() { return lt_cpu_get_freq(); }
+
+void arch_init();
+
+}  // namespace esphome
+
+#endif  // USE_LIBRETINY
diff --git a/esphome/components/light/automation.h b/esphome/components/light/automation.h
index f6a2ca52d4..993d4a2ea6 100644
--- a/esphome/components/light/automation.h
+++ b/esphome/components/light/automation.h
@@ -8,84 +8,66 @@ namespace esphome::light {
 
 enum class LimitMode { CLAMP, DO_NOTHING };
 
-template<typename... Ts> class ToggleAction : public Action<Ts...> {
+template<bool HasTransitionLength, typename... Ts> class ToggleAction : public Action<Ts...> {
  public:
   explicit ToggleAction(LightState *state) : state_(state) {}
 
-  TEMPLATABLE_VALUE(uint32_t, transition_length)
+  template<typename V> void set_transition_length(V value) requires(HasTransitionLength) {
+    this->transition_length_ = value;
+  }
 
   void play(const Ts &...x) override {
     auto call = this->state_->toggle();
-    call.set_transition_length(this->transition_length_.optional_value(x...));
+    if constexpr (HasTransitionLength) {
+      call.set_transition_length(this->transition_length_.optional_value(x...));
+    }
     call.perform();
   }
 
  protected:
   LightState *state_;
+  struct NoTransition {};
+  [[no_unique_address]] std::conditional_t<HasTransitionLength, TemplatableFn<uint32_t, Ts...>, NoTransition>
+      transition_length_{};
 };
 
+// All configured fields are baked into a single stateless lambda whose
+// constants live in flash. The action only stores one function pointer
+// plus one parent pointer, regardless of how many fields the user set.
+// Trigger args are forwarded to the apply function so user lambdas
+// (e.g. `brightness: !lambda "return x;"`) keep working.
+//
+// Trigger args are normalized to `const std::remove_cvref_t<Ts> &...` so
+// the codegen can emit a matching parameter list for both the apply lambda
+// and any inner field lambdas without producing invalid C++ source text
+// (e.g. `const T & &` if Ts already carries a reference, or `const const
+// T &` if Ts already carries a const). This keeps trigger args no-copy
+// regardless of whether the trigger supplies `T`, `T &`, or `const T &`.
 template<typename... Ts> class LightControlAction : public Action<Ts...> {
  public:
-  explicit LightControlAction(LightState *parent) : parent_(parent) {}
-
-  TEMPLATABLE_VALUE(ColorMode, color_mode)
-  TEMPLATABLE_VALUE(bool, state)
-  TEMPLATABLE_VALUE(uint32_t, transition_length)
-  TEMPLATABLE_VALUE(uint32_t, flash_length)
-  TEMPLATABLE_VALUE(float, brightness)
-  TEMPLATABLE_VALUE(float, color_brightness)
-  TEMPLATABLE_VALUE(float, red)
-  TEMPLATABLE_VALUE(float, green)
-  TEMPLATABLE_VALUE(float, blue)
-  TEMPLATABLE_VALUE(float, white)
-  TEMPLATABLE_VALUE(float, color_temperature)
-  TEMPLATABLE_VALUE(float, cold_white)
-  TEMPLATABLE_VALUE(float, warm_white)
-  TEMPLATABLE_VALUE(uint32_t, effect)
+  using ApplyFn = void (*)(LightState *, LightCall &, const std::remove_cvref_t<Ts> &...);
+  LightControlAction(LightState *parent, ApplyFn apply) : parent_(parent), apply_(apply) {}
 
   void play(const Ts &...x) override {
     auto call = this->parent_->make_call();
-    if (this->color_mode_.has_value())
-      call.set_color_mode(this->color_mode_.value(x...));
-    if (this->state_.has_value())
-      call.set_state(this->state_.value(x...));
-    if (this->transition_length_.has_value())
-      call.set_transition_length(this->transition_length_.value(x...));
-    if (this->flash_length_.has_value())
-      call.set_flash_length(this->flash_length_.value(x...));
-    if (this->brightness_.has_value())
-      call.set_brightness(this->brightness_.value(x...));
-    if (this->color_brightness_.has_value())
-      call.set_color_brightness(this->color_brightness_.value(x...));
-    if (this->red_.has_value())
-      call.set_red(this->red_.value(x...));
-    if (this->green_.has_value())
-      call.set_green(this->green_.value(x...));
-    if (this->blue_.has_value())
-      call.set_blue(this->blue_.value(x...));
-    if (this->white_.has_value())
-      call.set_white(this->white_.value(x...));
-    if (this->color_temperature_.has_value())
-      call.set_color_temperature(this->color_temperature_.value(x...));
-    if (this->cold_white_.has_value())
-      call.set_cold_white(this->cold_white_.value(x...));
-    if (this->warm_white_.has_value())
-      call.set_warm_white(this->warm_white_.value(x...));
-    if (this->effect_.has_value())
-      call.set_effect(this->effect_.value(x...));
+    this->apply_(this->parent_, call, x...);
     call.perform();
   }
 
  protected:
   LightState *parent_;
+  ApplyFn apply_;
 };
 
-template<typename... Ts> class DimRelativeAction : public Action<Ts...> {
+template<bool HasTransitionLength, typename... Ts> class DimRelativeAction : public Action<Ts...> {
  public:
   explicit DimRelativeAction(LightState *parent) : parent_(parent) {}
 
   TEMPLATABLE_VALUE(float, relative_brightness)
-  TEMPLATABLE_VALUE(uint32_t, transition_length)
+
+  template<typename V> void set_transition_length(V value) requires(HasTransitionLength) {
+    this->transition_length_ = value;
+  }
 
   void play(const Ts &...x) override {
     auto call = this->parent_->make_call();
@@ -99,7 +81,9 @@ template<typename... Ts> class DimRelativeAction : public Action<Ts...> {
     call.set_state(new_brightness != 0.0f);
     call.set_brightness(new_brightness);
 
-    call.set_transition_length(this->transition_length_.optional_value(x...));
+    if constexpr (HasTransitionLength) {
+      call.set_transition_length(this->transition_length_.optional_value(x...));
+    }
     call.perform();
   }
 
@@ -115,6 +99,9 @@ template<typename... Ts> class DimRelativeAction : public Action<Ts...> {
   float min_brightness_{0.0};
   float max_brightness_{1.0};
   LimitMode limit_mode_{LimitMode::CLAMP};
+  struct NoTransition {};
+  [[no_unique_address]] std::conditional_t<HasTransitionLength, TemplatableFn<uint32_t, Ts...>, NoTransition>
+      transition_length_{};
 };
 
 template<typename... Ts> class LightIsOnCondition : public Condition<Ts...> {
diff --git a/esphome/components/light/automation.py b/esphome/components/light/automation.py
index 46d37239e5..cef774af38 100644
--- a/esphome/components/light/automation.py
+++ b/esphome/components/light/automation.py
@@ -37,6 +37,7 @@ from .types import (
     AddressableSet,
     ColorMode,
     DimRelativeAction,
+    LightCall,
     LightControlAction,
     LightIsOffCondition,
     LightIsOnCondition,
@@ -60,8 +61,10 @@ from .types import (
 )
 async def light_toggle_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if CONF_TRANSITION_LENGTH in config:
+    has_transition_length = CONF_TRANSITION_LENGTH in config
+    toggle_template_arg = cg.TemplateArguments(has_transition_length, *template_arg)
+    var = cg.new_Pvariable(action_id, toggle_template_arg, paren)
+    if has_transition_length:
         template_ = await cg.templatable(
             config[CONF_TRANSITION_LENGTH], args, cg.uint32
         )
@@ -178,9 +181,9 @@ def _resolve_effect_index(config: ConfigType) -> int:
 )
 async def light_control_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
 
-    # (config_key, setter_name, c++ type)
+    # All configured fields are folded into a single stateless lambda whose
+    # constants live in flash; the action stores only a function pointer.
     FIELDS = (
         (CONF_COLOR_MODE, "set_color_mode", ColorMode),
         (CONF_STATE, "set_state", cg.bool_),
@@ -196,38 +199,58 @@ async def light_control_to_code(config, action_id, template_arg, args):
         (CONF_COLD_WHITE, "set_cold_white", cg.float_),
         (CONF_WARM_WHITE, "set_warm_white", cg.float_),
     )
+
+    # Normalize trigger args to `const std::remove_cvref_t<T> &` so the
+    # apply lambda and any inner field lambdas (generated below via
+    # `process_lambda`) share one parameter spelling that's well-formed for
+    # any T (value, ref, or const-ref). Matches LightControlAction::ApplyFn.
+    normalized_args = [
+        (cg.RawExpression(f"const std::remove_cvref_t<{cg.safe_exp(t)}> &"), n)
+        for t, n in args
+    ]
+
+    fwd_args = ", ".join(name for _, name in args)
+    body_lines: list[str] = []
+
     for conf_key, setter, type_ in FIELDS:
-        if conf_key in config:
-            template_ = await cg.templatable(config[conf_key], args, type_)
-            cg.add(getattr(var, setter)(template_))
+        if conf_key not in config:
+            continue
+        value = config[conf_key]
+        if isinstance(value, Lambda):
+            inner = await cg.process_lambda(value, normalized_args, return_type=type_)
+            body_lines.append(f"call.{setter}(({inner})({fwd_args}));")
+        else:
+            body_lines.append(f"call.{setter}({cg.safe_exp(value)});")
 
     if CONF_EFFECT in config:
         if isinstance(config[CONF_EFFECT], Lambda):
-            # Lambda returns a string — wrap in a C++ lambda that resolves
-            # the effect name to its uint32_t index at runtime
             inner_lambda = await cg.process_lambda(
-                config[CONF_EFFECT], args, return_type=cg.std_string
+                config[CONF_EFFECT], normalized_args, return_type=cg.std_string
             )
-            fwd_args = ", ".join(n for _, n in args)
-            # capture="" is correct: paren is a global variable name
-            # string-interpolated into the body at codegen time, not a
-            # C++ runtime capture.
-            wrapper = LambdaExpression(
-                f"auto __effect_s = ({inner_lambda})({fwd_args});\n"
-                f"return {paren}->get_effect_index("
-                f"__effect_s.c_str(), __effect_s.size());",
-                args,
-                capture="",
-                return_type=cg.uint32,
+            body_lines.append(
+                f"{{ auto __effect_s = ({inner_lambda})({fwd_args});\n"
+                f"call.set_effect(parent->get_effect_index("
+                f"__effect_s.c_str(), __effect_s.size())); }}"
             )
-            cg.add(var.set_effect(wrapper))
         else:
-            # Static string — resolve effect name to index at codegen time
-            template_ = await cg.templatable(
-                _resolve_effect_index(config), args, cg.uint32
+            # Cast disambiguates between set_effect(uint32_t) and
+            # set_effect(optional<uint32_t>) when the literal is an int.
+            body_lines.append(
+                f"call.set_effect(static_cast<uint32_t>({_resolve_effect_index(config)}));"
             )
-            cg.add(var.set_effect(template_))
-    return var
+
+    apply_args = [
+        (LightState.operator("ptr"), "parent"),
+        (LightCall.operator("ref"), "call"),
+        *normalized_args,
+    ]
+    apply_lambda = LambdaExpression(
+        ["\n".join(body_lines)],
+        apply_args,
+        capture="",
+        return_type=cg.void,
+    )
+    return cg.new_Pvariable(action_id, template_arg, paren, apply_lambda)
 
 
 CONF_RELATIVE_BRIGHTNESS = "relative_brightness"
@@ -261,10 +284,12 @@ LIGHT_DIM_RELATIVE_ACTION_SCHEMA = cv.Schema(
 )
 async def light_dim_relative_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
+    has_transition_length = CONF_TRANSITION_LENGTH in config
+    dim_template_arg = cg.TemplateArguments(has_transition_length, *template_arg)
+    var = cg.new_Pvariable(action_id, dim_template_arg, paren)
     templ = await cg.templatable(config[CONF_RELATIVE_BRIGHTNESS], args, cg.float_)
     cg.add(var.set_relative_brightness(templ))
-    if CONF_TRANSITION_LENGTH in config:
+    if has_transition_length:
         templ = await cg.templatable(config[CONF_TRANSITION_LENGTH], args, cg.uint32)
         cg.add(var.set_transition_length(templ))
     if conf := config.get(CONF_BRIGHTNESS_LIMITS):
diff --git a/esphome/components/light/types.py b/esphome/components/light/types.py
index a586bcbd13..534dcd2194 100644
--- a/esphome/components/light/types.py
+++ b/esphome/components/light/types.py
@@ -13,6 +13,7 @@ Color = cg.esphome_ns.class_("Color")
 LightColorValues = light_ns.class_("LightColorValues")
 
 LightStateRTCState = light_ns.struct("LightStateRTCState")
+LightCall = light_ns.class_("LightCall")
 
 # Color modes
 ColorMode = light_ns.enum("ColorMode", is_class=True)
diff --git a/esphome/components/lvgl/binary_sensor/__init__.py b/esphome/components/lvgl/binary_sensor/__init__.py
index f9df7d23fa..aa68e76421 100644
--- a/esphome/components/lvgl/binary_sensor/__init__.py
+++ b/esphome/components/lvgl/binary_sensor/__init__.py
@@ -4,15 +4,25 @@ from esphome.components.binary_sensor import (
     new_binary_sensor,
 )
 import esphome.config_validation as cv
+from esphome.const import CONF_STATE
 
-from ..defines import CONF_WIDGET
-from ..lvcode import EVENT_ARG, LambdaContext, LvContext, lvgl_static
-from ..types import LV_EVENT, lv_pseudo_button_t
+from ..defines import CONF_WIDGET, LV_OBJ_FLAG, LvConstant
+from ..lvcode import EVENT_ARG, UPDATE_EVENT, LambdaContext, LvContext, lvgl_static
+from ..types import LV_EVENT, LV_STATE, lv_pseudo_button_t
 from ..widgets import Widget, get_widgets, wait_for_widgets
 
+STATE_PRESSED = "PRESSED"
+STATE_CHECKED = "CHECKED"
+
+BS_STATE = LvConstant(
+    "LV_STATE_",
+    STATE_PRESSED,
+    STATE_CHECKED,
+)
 CONFIG_SCHEMA = binary_sensor_schema(BinarySensor).extend(
     {
         cv.Required(CONF_WIDGET): cv.use_id(lv_pseudo_button_t),
+        cv.Optional(CONF_STATE, default=STATE_PRESSED): BS_STATE.one_of,
     }
 )
 
@@ -22,16 +32,23 @@ async def to_code(config):
     widget = await get_widgets(config, CONF_WIDGET)
     widget = widget[0]
     assert isinstance(widget, Widget)
+    state = await BS_STATE.process(config[CONF_STATE])
     await wait_for_widgets()
-    async with LambdaContext(EVENT_ARG) as pressed_ctx:
-        pressed_ctx.add(sensor.publish_state(widget.is_pressed()))
+    is_pressed = str(state) == str(LV_STATE.PRESSED)
+    test_expr = widget.is_pressed() if is_pressed else widget.is_checked()
+    async with LambdaContext(EVENT_ARG) as test_ctx:
+        test_ctx.add(sensor.publish_state(test_expr))
     async with LvContext() as ctx:
-        ctx.add(sensor.publish_initial_state(widget.is_pressed()))
+        ctx.add(sensor.publish_initial_state(test_expr))
+        if is_pressed:
+            events = [LV_EVENT.PRESSED, LV_EVENT.RELEASED]
+            widget.add_flag(LV_OBJ_FLAG.CLICKABLE)
+        else:
+            events = [LV_EVENT.VALUE_CHANGED, UPDATE_EVENT]
         ctx.add(
             lvgl_static.add_event_cb(
                 widget.obj,
-                await pressed_ctx.get_lambda(),
-                LV_EVENT.PRESSED,
-                LV_EVENT.RELEASED,
+                await test_ctx.get_lambda(),
+                *events,
             )
         )
diff --git a/esphome/components/lvgl/gradient.py b/esphome/components/lvgl/gradient.py
index c4a3c8f2cb..e075433d03 100644
--- a/esphome/components/lvgl/gradient.py
+++ b/esphome/components/lvgl/gradient.py
@@ -1,3 +1,5 @@
+from operator import itemgetter
+
 from esphome import config_validation as cv
 import esphome.codegen as cg
 from esphome.const import (
@@ -11,6 +13,7 @@ from esphome.core import ID
 from esphome.cpp_generator import MockObj
 
 from .defines import CONF_GRADIENTS, CONF_OPA, LV_DITHER, add_define, add_warning
+from .helpers import add_lv_use
 from .lv_validation import lv_color, lv_percentage, opacity
 from .lvcode import lv
 from .types import lv_color_t, lv_gradient_t, lv_opa_t
@@ -50,6 +53,7 @@ GRADIENT_SCHEMA = cv.ensure_list(
 
 
 async def gradients_to_code(config):
+    add_lv_use("gradient")
     max_stops = 2
     if any(CONF_DITHER in x for x in config.get(CONF_GRADIENTS, ())):
         add_warning(
@@ -58,7 +62,7 @@ async def gradients_to_code(config):
     for gradient in config.get(CONF_GRADIENTS, ()):
         var = MockObj(cg.new_Pvariable(gradient[CONF_ID]), "->")
         idbase = gradient[CONF_ID].id
-        stops = gradient[CONF_STOPS]
+        stops = sorted(gradient[CONF_STOPS], key=itemgetter(CONF_POSITION))
         max_stops = max(max_stops, len(stops))
         if gradient[CONF_DIRECTION].startswith("VER"):
             lv.grad_vertical_init(var)
diff --git a/esphome/components/lvgl/layout.py b/esphome/components/lvgl/layout.py
index 46026852af..32304276d3 100644
--- a/esphome/components/lvgl/layout.py
+++ b/esphome/components/lvgl/layout.py
@@ -1,3 +1,4 @@
+import math
 import re
 import textwrap
 
@@ -85,6 +86,22 @@ def grid_free_space(value):
 
 grid_spec = cv.Any(size, LvConstant("LV_GRID_", "CONTENT").one_of, grid_free_space)
 
+
+def grid_dimension(value):
+    """
+    Validator for a grid `rows` or `columns` value.
+    Accepts either a positive integer (interpreted as that many cells of equal
+    `LV_GRID_FR(1)` size) or a non-empty list of grid specs.
+    """
+    if isinstance(value, int):
+        value = cv.int_range(min=1)(value)
+        return ["LV_GRID_FR(1)"] * value
+    result = cv.Schema([grid_spec])(value)
+    if not result:
+        raise cv.Invalid("Grid dimension list must contain at least one entry")
+    return result
+
+
 GRID_CELL_SCHEMA = {
     cv.Optional(CONF_GRID_CELL_ROW_POS): cv.positive_int,
     cv.Optional(CONF_GRID_CELL_COLUMN_POS): cv.positive_int,
@@ -184,7 +201,16 @@ class DirectionalLayout(FlexLayout):
 
 
 class GridLayout(Layout):
-    _GRID_LAYOUT_REGEX = re.compile(r"^\s*(\d+)\s*x\s*(\d+)\s*$")
+    # Match shorthand grid layout strings: "NxM", "Nx" or "xM".
+    # At least one of the two numbers must be present; this is enforced after matching.
+    _GRID_LAYOUT_REGEX = re.compile(r"^\s*(\d+)?\s*x\s*(\d+)?\s*$")
+
+    @staticmethod
+    def _match_shorthand(layout):
+        match = GridLayout._GRID_LAYOUT_REGEX.match(layout)
+        if match is None or (match.group(1) is None and match.group(2) is None):
+            return None
+        return match
 
     def get_type(self):
         return TYPE_GRID
@@ -192,7 +218,7 @@ class GridLayout(Layout):
     def get_layout_schemas(self, config: dict) -> tuple:
         layout = config.get(CONF_LAYOUT)
         if isinstance(layout, str):
-            if GridLayout._GRID_LAYOUT_REGEX.match(layout):
+            if GridLayout._match_shorthand(layout):
                 return (
                     cv.string,
                     {
@@ -213,59 +239,107 @@ class GridLayout(Layout):
 
         if not isinstance(layout, dict) or layout.get(CONF_TYPE).lower() != TYPE_GRID:
             return None, {}
+        x_default = (
+            "center" if isinstance(layout.get(CONF_GRID_ROWS), int) else cv.UNDEFINED
+        )
+        y_default = (
+            "center" if isinstance(layout.get(CONF_GRID_COLUMNS), int) else cv.UNDEFINED
+        )
+        x_align = layout.get(CONF_GRID_CELL_X_ALIGN, x_default)
+        y_align = layout.get(CONF_GRID_CELL_Y_ALIGN, y_default)
         return (
             {
                 cv.Required(CONF_TYPE): cv.one_of(TYPE_GRID, lower=True),
-                cv.Required(CONF_GRID_ROWS): [grid_spec],
-                cv.Required(CONF_GRID_COLUMNS): [grid_spec],
+                cv.Optional(CONF_GRID_ROWS): grid_dimension,
+                cv.Optional(CONF_GRID_COLUMNS): grid_dimension,
                 cv.Optional(CONF_GRID_COLUMN_ALIGN): grid_alignments,
                 cv.Optional(CONF_GRID_ROW_ALIGN): grid_alignments,
                 cv.Optional(CONF_PAD_ROW): padding,
                 cv.Optional(CONF_PAD_COLUMN): padding,
                 cv.Optional(CONF_MULTIPLE_WIDGETS_PER_CELL, default=False): cv.boolean,
+                cv.Optional(CONF_GRID_CELL_X_ALIGN): grid_alignments,
+                cv.Optional(CONF_GRID_CELL_Y_ALIGN): grid_alignments,
             },
             {
                 cv.Optional(CONF_GRID_CELL_ROW_POS): cv.positive_int,
                 cv.Optional(CONF_GRID_CELL_COLUMN_POS): cv.positive_int,
                 cv.Optional(CONF_GRID_CELL_ROW_SPAN): cv.int_range(min=1),
                 cv.Optional(CONF_GRID_CELL_COLUMN_SPAN): cv.int_range(min=1),
-                cv.Optional(CONF_GRID_CELL_X_ALIGN): grid_alignments,
-                cv.Optional(CONF_GRID_CELL_Y_ALIGN): grid_alignments,
+                cv.Optional(CONF_GRID_CELL_X_ALIGN, default=x_align): grid_alignments,
+                cv.Optional(CONF_GRID_CELL_Y_ALIGN, default=y_align): grid_alignments,
             },
         )
 
     def validate(self, config: dict):
         """
         Validate the grid layout.
-        The `layout:` key may be a dictionary with `rows` and `columns` keys, or a string in the format "rows x columns".
+        The `layout:` key may be a dictionary with `rows` and/or `columns` keys, or a
+        shorthand string in the format "<rows>x<columns>", "<rows>x" or "x<columns>".
+        Either dimension may be omitted, in which case it will be calculated from the
+        other dimension and the number of configured widgets.
         Either all cells must have a row and column,
         or none, in which case the grid layout is auto-generated.
         :param config:
         :return: The config updated with auto-generated values
         """
         layout = config.get(CONF_LAYOUT)
+        widgets = config.get(CONF_WIDGETS, [])
+        num_widgets = len(widgets)
         if isinstance(layout, str):
-            # If the layout is a string, assume it is in the format "rows x columns", implying
-            # a grid layout with the specified number of rows and columns each with CONTENT sizing.
+            # Shorthand string: "<rows>x<columns>", "<rows>x" or "x<columns>".
+            # Each dimension defaults to LV_GRID_FR(1). A missing dimension is
+            # calculated from the other dimension and the number of widgets.
             layout = layout.strip()
-            match = GridLayout._GRID_LAYOUT_REGEX.match(layout)
-            if match:
-                rows = int(match.group(1))
-                cols = int(match.group(2))
-                layout = {
-                    CONF_TYPE: TYPE_GRID,
-                    CONF_GRID_ROWS: ["LV_GRID_FR(1)"] * rows,
-                    CONF_GRID_COLUMNS: ["LV_GRID_FR(1)"] * cols,
-                }
-                config[CONF_LAYOUT] = layout
-            else:
+            match = GridLayout._match_shorthand(layout)
+            if not match:
                 raise cv.Invalid(
-                    f"Invalid grid layout format: {config}, expected 'rows x columns'",
+                    f"Invalid grid layout format: {layout!r}, expected "
+                    "'<rows>x<columns>', '<rows>x' or 'x<columns>'",
                     [CONF_LAYOUT],
                 )
+            rows_int = int(match.group(1)) if match.group(1) is not None else None
+            cols_int = int(match.group(2)) if match.group(2) is not None else None
+            for label, val in (("row", rows_int), ("column", cols_int)):
+                if val is not None and val < 1:
+                    raise cv.Invalid(
+                        f"Invalid grid layout {layout!r}: {label} count must be "
+                        "at least 1",
+                        [CONF_LAYOUT],
+                    )
+            if rows_int is not None and cols_int is not None:
+                rows = rows_int
+                cols = cols_int
+            elif rows_int is not None:
+                rows = rows_int
+                cols = max(1, math.ceil(num_widgets / rows)) if num_widgets else 1
+            else:
+                cols = cols_int
+                rows = max(1, math.ceil(num_widgets / cols)) if num_widgets else 1
+            layout = {
+                CONF_TYPE: TYPE_GRID,
+                CONF_GRID_ROWS: ["LV_GRID_FR(1)"] * rows,
+                CONF_GRID_COLUMNS: ["LV_GRID_FR(1)"] * cols,
+            }
+            config[CONF_LAYOUT] = layout
         # should be guaranteed to be a dict at this point
         assert isinstance(layout, dict)
         assert layout.get(CONF_TYPE).lower() == TYPE_GRID
+        rows_list = layout.get(CONF_GRID_ROWS)
+        cols_list = layout.get(CONF_GRID_COLUMNS)
+        if rows_list is None and cols_list is None:
+            raise cv.Invalid(
+                "Grid layout requires at least one of 'rows' or 'columns' to be "
+                "specified",
+                [CONF_LAYOUT],
+            )
+        if rows_list is None:
+            cols = len(cols_list)
+            rows = max(1, math.ceil(num_widgets / cols)) if num_widgets else 1
+            layout[CONF_GRID_ROWS] = ["LV_GRID_FR(1)"] * rows
+        elif cols_list is None:
+            rows = len(rows_list)
+            cols = max(1, math.ceil(num_widgets / rows)) if num_widgets else 1
+            layout[CONF_GRID_COLUMNS] = ["LV_GRID_FR(1)"] * cols
         allow_multiple = layout.get(CONF_MULTIPLE_WIDGETS_PER_CELL, False)
         rows = len(layout[CONF_GRID_ROWS])
         columns = len(layout[CONF_GRID_COLUMNS])
@@ -379,7 +453,8 @@ def append_layout_schema(schema, config: dict):
         textwrap.dedent(
             """
                 Invalid 'layout' value
-                layout choices are 'horizontal', 'vertical', '<rows>x<cols>',
+                layout choices are 'horizontal', 'vertical',
+                '<rows>x<cols>', '<rows>x', 'x<cols>',
                 or a dictionary with a 'type' key
             """
         ),
diff --git a/esphome/components/lvgl/lvgl_esphome.cpp b/esphome/components/lvgl/lvgl_esphome.cpp
index d8248e4aa4..eb85faa16c 100644
--- a/esphome/components/lvgl/lvgl_esphome.cpp
+++ b/esphome/components/lvgl/lvgl_esphome.cpp
@@ -454,10 +454,12 @@ void LVTouchListener::update(const touchscreen::TouchPoints_t &tpoints) {
 
 #ifdef USE_LVGL_METER
 
-int16_t lv_get_needle_angle_for_value(lv_obj_t *obj, int value) {
+int16_t lv_get_needle_angle_for_value(lv_obj_t *obj, int32_t value) {
   auto *scale = lv_obj_get_parent(obj);
   auto min_value = lv_scale_get_range_min_value(scale);
-  return ((value - min_value) * lv_scale_get_angle_range(scale) / (lv_scale_get_range_max_value(scale) - min_value) +
+  auto max_value = lv_scale_get_range_max_value(scale);
+  value = clamp(value, min_value, max_value);
+  return ((value - min_value) * lv_scale_get_angle_range(scale) / (max_value - min_value) +
           lv_scale_get_rotation((scale))) %
          360;
 }
@@ -864,6 +866,32 @@ void lv_scale_draw_event_cb(lv_event_t *e, int16_t range_start, int16_t range_en
 }
 #endif  // USE_LVGL_SCALE
 
+#ifdef USE_LVGL_GRADIENT
+/**
+ *
+ * @param dsc The gradient descriptor containing the color stops
+ * @param pos The current position to calculate the color for
+ * @return The color for the given position
+ */
+
+lv_color_t lv_grad_calculate_color(const lv_grad_dsc_t *dsc, int32_t pos) {
+  if (dsc->stops_count == 0)
+    return lv_color_black();
+  if (dsc->stops_count == 1 || pos <= dsc->stops[0].frac)
+    return dsc->stops[0].color;
+  if (pos >= dsc->stops[dsc->stops_count - 1].frac)
+    return dsc->stops[dsc->stops_count - 1].color;
+  int i = 1;
+  while (i < dsc->stops_count && dsc->stops[i].frac < pos)
+    i++;
+  auto *stop1 = &dsc->stops[i - 1];
+  auto *stop2 = &dsc->stops[i];
+  int32_t range = stop2->frac - stop1->frac;
+  int32_t offset = pos - stop1->frac;
+  return lv_color_mix(stop2->color, stop1->color, range == 0 ? 0 : (offset * 255) / range);
+}
+#endif
+
 static void lv_container_constructor(const lv_obj_class_t *class_p, lv_obj_t *obj) {
   LV_TRACE_OBJ_CREATE("begin");
   LV_UNUSED(class_p);
diff --git a/esphome/components/lvgl/lvgl_esphome.h b/esphome/components/lvgl/lvgl_esphome.h
index 146866f5bd..be1f150aff 100644
--- a/esphome/components/lvgl/lvgl_esphome.h
+++ b/esphome/components/lvgl/lvgl_esphome.h
@@ -112,9 +112,19 @@ inline void lv_animimg_set_src(lv_obj_t *img, std::vector<image::Image *> images
 #endif  // USE_LVGL_ANIMIMG
 
 #ifdef USE_LVGL_METER
-int16_t lv_get_needle_angle_for_value(lv_obj_t *obj, int value);
+int16_t lv_get_needle_angle_for_value(lv_obj_t *obj, int32_t value);
 #endif
 
+#ifdef USE_LVGL_GRADIENT
+/**
+ *
+ * @param dsc The gradient descriptor containing the color stops
+ * @param pos The current position to calculate the color for
+ * @return The color for the given position
+ */
+
+lv_color_t lv_grad_calculate_color(const lv_grad_dsc_t *dsc, int32_t pos);
+#endif
 // Parent class for things that wrap an LVGL object
 class LvCompound {
  public:
diff --git a/esphome/components/mapping/__init__.py b/esphome/components/mapping/__init__.py
index a36b414fd5..3c7d78a27b 100644
--- a/esphome/components/mapping/__init__.py
+++ b/esphome/components/mapping/__init__.py
@@ -1,18 +1,27 @@
+from collections.abc import Callable
 import difflib
 
 import esphome.codegen as cg
+from esphome.components.const import KEY_METADATA
 import esphome.config_validation as cv
 from esphome.const import CONF_FROM, CONF_ID, CONF_TO
-from esphome.core import CORE
-from esphome.cpp_generator import MockObj, VariableDeclarationExpression, add_global
+from esphome.core import CORE, ID
+from esphome.cpp_generator import (
+    MockObj,
+    MockObjClass,
+    VariableDeclarationExpression,
+    add_global,
+)
 from esphome.loader import get_component
 
 CODEOWNERS = ["@clydebarrow"]
 MULTI_CONF = True
+DOMAIN = "mapping"
 
 mapping_ns = cg.esphome_ns.namespace("mapping")
 mapping_class = mapping_ns.class_("Mapping")
 
+CONF_DEFAULT_VALUE = "default_value"
 CONF_ENTRIES = "entries"
 CONF_CLASS = "class"
 
@@ -22,11 +31,18 @@ class IndexType:
     Represents a type of index in a map.
     """
 
-    def __init__(self, validator, data_type, conversion):
+    def __init__(
+        self, validator: Callable, data_type: MockObj, conversion: Callable = None
+    ) -> None:
         self.validator = validator
         self.data_type = data_type
         self.conversion = conversion
 
+    async def convert_value(self, value):
+        if self.conversion:
+            return self.conversion(value)
+        return await cg.get_variable(value)
+
 
 INDEX_TYPES = {
     "int": IndexType(cv.int_, cg.int_, int),
@@ -38,6 +54,12 @@ INDEX_TYPES = {
 }
 
 
+class MappingMetaData:
+    def __init__(self, from_: IndexType, to_: IndexType) -> None:
+        self.from_ = from_
+        self.to_ = to_
+
+
 def to_schema(value):
     """
     Generate a schema for the 'to' field of a map. This can be either one of the index types or a class name.
@@ -60,7 +82,7 @@ BASE_SCHEMA = cv.Schema(
 )
 
 
-def get_object_type(to_):
+def get_object_type(to_) -> MockObjClass | None:
     """
     Get the object type from a string. Possible formats:
        xxx The name of a component which defines INSTANCE_TYPE
@@ -81,25 +103,60 @@ def get_object_type(to_):
     return None
 
 
+def get_all_mapping_metadata() -> dict[str, MappingMetaData]:
+    """Get all mapping metadata."""
+    return CORE.data.setdefault(DOMAIN, {}).setdefault(KEY_METADATA, {})
+
+
+def get_mapping_metadata(mapping_id: str) -> MappingMetaData:
+    """Get mapping metadata by ID for use by other components."""
+    return get_all_mapping_metadata()[mapping_id]
+
+
+def add_metadata(
+    mapping_id: ID,
+    from_: IndexType,
+    to_: IndexType,
+) -> None:
+    get_all_mapping_metadata()[mapping_id.id] = MappingMetaData(from_, to_)
+
+
 def map_schema(config):
     config = BASE_SCHEMA(config)
     if CONF_ENTRIES not in config or not isinstance(config[CONF_ENTRIES], dict):
-        raise cv.Invalid("an entries list is required for a map")
+        raise cv.Invalid("an entries dictionary is required for a mapping")
     entries = config[CONF_ENTRIES]
     if len(entries) == 0:
-        raise cv.Invalid("Map must have at least one entry")
+        raise cv.Invalid("A mapping must have at least one entry")
     to_ = config[CONF_TO]
     if to_ in INDEX_TYPES:
-        value_type = INDEX_TYPES[to_].validator
+        value_type = INDEX_TYPES[to_]
     else:
-        value_type = get_object_type(to_)
-        if value_type is None:
+        object_type = get_object_type(to_)
+        if object_type is None:
             matches = difflib.get_close_matches(to_, CORE.id_classes)
             raise cv.Invalid(
                 f"No known mappable class name matches '{to_}'; did you mean one of {', '.join(matches)}?"
             )
-        value_type = cv.use_id(value_type)
-    config[CONF_ENTRIES] = {k: value_type(v) for k, v in entries.items()}
+        validator = cv.use_id(object_type)
+        value_type = IndexType(validator, object_type)
+    config[CONF_ENTRIES] = {k: value_type.validator(v) for k, v in entries.items()}
+    if (default_value := config.get(CONF_DEFAULT_VALUE)) is not None:
+        config[CONF_DEFAULT_VALUE] = value_type.validator(default_value)
+    unexpected_keys = config.keys() - {
+        CONF_ENTRIES,
+        CONF_TO,
+        CONF_FROM,
+        CONF_ID,
+        CONF_DEFAULT_VALUE,
+    }
+    if unexpected_keys:
+        errors = [
+            cv.Invalid(f"Unexpected key '{k}'", path=[k]) for k in unexpected_keys
+        ]
+        raise cv.MultipleInvalid(errors)
+
+    add_metadata(config[CONF_ID], INDEX_TYPES[config[CONF_FROM]], value_type)
     return config
 
 
@@ -107,29 +164,19 @@ CONFIG_SCHEMA = map_schema
 
 
 async def to_code(config):
-    entries = config[CONF_ENTRIES]
-    from_ = config[CONF_FROM]
-    to_ = config[CONF_TO]
-    index_conversion = INDEX_TYPES[from_].conversion
-    index_type = INDEX_TYPES[from_].data_type
-    if to_ in INDEX_TYPES:
-        value_conversion = INDEX_TYPES[to_].conversion
-        value_type = INDEX_TYPES[to_].data_type
-        entries = {
-            index_conversion(key): value_conversion(value)
-            for key, value in entries.items()
-        }
-    else:
-        entries = {
-            index_conversion(key): await cg.get_variable(value)
-            for key, value in entries.items()
-        }
-        value_type = get_object_type(to_)
-        if list(entries.values())[0].op != ".":
-            value_type = value_type.operator("ptr")
     varid = config[CONF_ID]
+    metadata = get_mapping_metadata(varid.id)
+    entries = {
+        metadata.from_.conversion(key): await metadata.to_.convert_value(value)
+        for key, value in config[CONF_ENTRIES].items()
+    }
+    value_type = metadata.to_.data_type
+    # entries guaranteed to be non-empty here.
+    value_0 = list(entries.values())[0]
+    if isinstance(value_0, MockObj) and value_0.op != ".":
+        value_type = value_type.operator("ptr")
     varid.type = mapping_class.template(
-        index_type,
+        metadata.from_.data_type,
         value_type,
     )
     var = MockObj(varid, ".")
@@ -139,4 +186,6 @@ async def to_code(config):
 
     for key, value in entries.items():
         cg.add(var.set(key, value))
+    if (default_value := config.get(CONF_DEFAULT_VALUE)) is not None:
+        cg.add(var.set_default_value(await metadata.to_.convert_value(default_value)))
     return var
diff --git a/esphome/components/mapping/mapping.h b/esphome/components/mapping/mapping.h
index 2b8f0d39b2..d6790caa35 100644
--- a/esphome/components/mapping/mapping.h
+++ b/esphome/components/mapping/mapping.h
@@ -40,6 +40,9 @@ template<typename K, typename V> class Mapping {
     if (it != this->map_.end()) {
       return V{it->second};
     }
+    if (this->default_value_.has_value()) {
+      return this->default_value_.value();
+    }
     if constexpr (std::is_pointer_v<K>) {
       esph_log_e(TAG, "Key '%p' not found in mapping", key);
     } else if constexpr (std::is_same_v<K, std::string>) {
@@ -69,11 +72,17 @@ template<typename K, typename V> class Mapping {
     if (it != this->map_.end()) {
       return it->second.c_str();  // safe since value remains in map
     }
+    if (this->default_value_.has_value()) {
+      return this->default_value_.value();
+    }
     return "";
   }
 
+  void set_default_value(const V &default_value) { this->default_value_ = default_value; }
+
  protected:
   std::map<key_t, value_t, std::less<key_t>, RAMAllocator<std::pair<key_t, value_t>>> map_;
+  std::optional<V> default_value_{};
 };
 
 }  // namespace esphome::mapping
diff --git a/esphome/components/mcp23xxx_base/__init__.py b/esphome/components/mcp23xxx_base/__init__.py
index cd952099c0..76a3aabe3f 100644
--- a/esphome/components/mcp23xxx_base/__init__.py
+++ b/esphome/components/mcp23xxx_base/__init__.py
@@ -2,6 +2,7 @@ from esphome import pins
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.const import (
+    CONF_ALLOW_OTHER_USES,
     CONF_ID,
     CONF_INPUT,
     CONF_INTERRUPT,
@@ -30,10 +31,29 @@ MCP23XXX_INTERRUPT_MODES = {
     "FALLING": MCP23XXXInterruptMode.MCP23XXX_FALLING,
 }
 
+
+def _validate_interrupt_pin(value):
+    # The MCP component owns INT polarity (active-low, hardcoded falling-edge ISR)
+    # and installs a single ISR per GPIO, so neither inversion nor sharing is supported.
+    value = pins.internal_gpio_input_pin_schema(value)
+    if value.get(CONF_INVERTED):
+        raise cv.Invalid(
+            f"'{CONF_INVERTED}: true' is not supported on '{CONF_INTERRUPT_PIN}'; "
+            "the MCP23xxx INT line is fixed active-low"
+        )
+    if value.get(CONF_ALLOW_OTHER_USES):
+        raise cv.Invalid(
+            f"'{CONF_ALLOW_OTHER_USES}: true' is not supported on '{CONF_INTERRUPT_PIN}'; "
+            "sharing the interrupt pin between multiple MCP23xxx (or other components) "
+            "is not implemented. Remove the interrupt_pin to fall back to polling."
+        )
+    return value
+
+
 MCP23XXX_CONFIG_SCHEMA = cv.Schema(
     {
         cv.Optional(CONF_OPEN_DRAIN_INTERRUPT, default=False): cv.boolean,
-        cv.Optional(CONF_INTERRUPT_PIN): pins.internal_gpio_input_pin_schema,
+        cv.Optional(CONF_INTERRUPT_PIN): _validate_interrupt_pin,
     }
 ).extend(cv.COMPONENT_SCHEMA)
 
diff --git a/esphome/components/mdns/__init__.py b/esphome/components/mdns/__init__.py
index 7c36295e8d..2b25cf243d 100644
--- a/esphome/components/mdns/__init__.py
+++ b/esphome/components/mdns/__init__.py
@@ -14,6 +14,7 @@ from esphome.const import (
 from esphome.core import CORE, Lambda, coroutine_with_priority
 from esphome.coroutine import CoroPriority
 from esphome.cpp_generator import LambdaExpression
+import esphome.final_validate as fv
 from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core"]
@@ -61,6 +62,28 @@ def _consume_mdns_sockets(config: ConfigType) -> ConfigType:
     return config
 
 
+def _require_network_interface(config: ConfigType) -> ConfigType:
+    """Require a network interface for mDNS on Arduino/LEAmDNS platforms.
+
+    On ESP8266 and RP2040 the C++ implementation needs at least one IP state
+    listener (WiFi on ESP8266; WiFi or Ethernet on RP2040) to arm its polling
+    window. Reject at config time rather than silently producing a component
+    that never initializes.
+    """
+    if config.get(CONF_DISABLED) or not (CORE.is_esp8266 or CORE.is_rp2040):
+        return config
+    full_config = fv.full_config.get()
+    has_wifi = "wifi" in full_config
+    has_ethernet = CORE.is_rp2040 and "ethernet" in full_config
+    if not (has_wifi or has_ethernet):
+        options = "'wifi'" if CORE.is_esp8266 else "'wifi' or 'ethernet'"
+        raise cv.Invalid(
+            "mdns on this platform requires a network interface — "
+            f"add a {options} component to your configuration."
+        )
+    return config
+
+
 CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
@@ -74,6 +97,9 @@ CONFIG_SCHEMA = cv.All(
 )
 
 
+FINAL_VALIDATE_SCHEMA = _require_network_interface
+
+
 def mdns_txt_record(key: str, value: str) -> cg.RawExpression:
     """Create a mDNS TXT record.
 
@@ -169,6 +195,19 @@ async def to_code(config):
         elif CORE.is_rp2040:
             cg.add_library("LEAmDNS", None)
 
+        # Subscribe to the network IP state listener(s) so MDNS.update() is only
+        # scheduled during the probe+announce phase. Same on_ip_state() override
+        # serves both WiFi and Ethernet (signatures match).
+        if CORE.is_esp8266 or CORE.is_rp2040:
+            if "wifi" in CORE.config:
+                from esphome.components import wifi
+
+                wifi.request_wifi_ip_state_listener()
+            if CORE.is_rp2040 and "ethernet" in CORE.config:
+                from esphome.components import ethernet
+
+                ethernet.request_ethernet_ip_state_listener()
+
     if CORE.is_esp32:
         add_idf_component(name="espressif/mdns", ref="1.11.0")
 
diff --git a/esphome/components/mdns/mdns_component.cpp b/esphome/components/mdns/mdns_component.cpp
index e05373ac5d..9bf27e71e4 100644
--- a/esphome/components/mdns/mdns_component.cpp
+++ b/esphome/components/mdns/mdns_component.cpp
@@ -39,7 +39,39 @@ MDNS_STATIC_CONST_CHAR(SERVICE_TCP, "_tcp");
 // Wrap build-time defines into flash storage
 MDNS_STATIC_CONST_CHAR(VALUE_VERSION, ESPHOME_VERSION);
 
-void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services, char *mac_address_buf) {
+void MDNSComponent::setup_buffers_and_register_(PlatformRegisterFn platform_register) {
+#ifdef USE_MDNS_STORE_SERVICES
+  auto &services = this->services_;
+#else
+  StaticVector<MDNSService, MDNS_SERVICE_COUNT> services_storage;
+  auto &services = services_storage;
+#endif
+
+#ifdef USE_API
+#ifdef USE_MDNS_STORE_SERVICES
+  get_mac_address_into_buffer(this->mac_address_);
+  char *mac_ptr = this->mac_address_;
+  format_hex_to(this->config_hash_str_, App.get_config_hash());
+  char *cfg_ptr = this->config_hash_str_;
+#else
+  char mac_address[MAC_ADDRESS_BUFFER_SIZE];
+  char config_hash_str[CONFIG_HASH_STR_SIZE];
+  get_mac_address_into_buffer(mac_address);
+  format_hex_to(config_hash_str, App.get_config_hash());
+  char *mac_ptr = mac_address;
+  char *cfg_ptr = config_hash_str;
+#endif
+#else
+  char *mac_ptr = nullptr;
+  char *cfg_ptr = nullptr;
+#endif
+
+  this->compile_records_(services, mac_ptr, cfg_ptr);
+  platform_register(this, services);
+}
+
+void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services, char *mac_address_buf,
+                                     char *config_hash_buf) {
   // IMPORTANT: The #ifdef blocks below must match COMPONENTS_WITH_MDNS_SERVICES
   // in mdns/__init__.py. If you add a new service here, update both locations.
 
@@ -47,6 +79,7 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
   MDNS_STATIC_CONST_CHAR(SERVICE_ESPHOMELIB, "_esphomelib");
   MDNS_STATIC_CONST_CHAR(TXT_FRIENDLY_NAME, "friendly_name");
   MDNS_STATIC_CONST_CHAR(TXT_VERSION, "version");
+  MDNS_STATIC_CONST_CHAR(TXT_CONFIG_HASH, "config_hash");
   MDNS_STATIC_CONST_CHAR(TXT_MAC, "mac");
   MDNS_STATIC_CONST_CHAR(TXT_PLATFORM, "platform");
   MDNS_STATIC_CONST_CHAR(TXT_BOARD, "board");
@@ -63,7 +96,7 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
     bool friendly_name_empty = friendly_name.empty();
 
     // Calculate exact capacity for txt_records
-    size_t txt_count = 3;  // version, mac, board (always present)
+    size_t txt_count = 4;  // version, config_hash, mac, board (always present)
     if (!friendly_name_empty) {
       txt_count++;  // friendly_name
     }
@@ -91,6 +124,9 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
     }
     txt_records.push_back({MDNS_STR(TXT_VERSION), MDNS_STR(VALUE_VERSION)});
 
+    // Config hash: passed from caller (either member buffer or stack buffer depending on USE_MDNS_STORE_SERVICES)
+    txt_records.push_back({MDNS_STR(TXT_CONFIG_HASH), MDNS_STR(config_hash_buf)});
+
     // MAC address: passed from caller (either member buffer or stack buffer depending on USE_MDNS_STORE_SERVICES)
     txt_records.push_back({MDNS_STR(TXT_MAC), MDNS_STR(mac_address_buf)});
 
diff --git a/esphome/components/mdns/mdns_component.h b/esphome/components/mdns/mdns_component.h
index adf88a9cf1..e981a65941 100644
--- a/esphome/components/mdns/mdns_component.h
+++ b/esphome/components/mdns/mdns_component.h
@@ -5,6 +5,22 @@
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
+// On ESP8266 and RP2040 the scheduler-backed MDNS.update() polling window is armed by
+// IP state listener events on whichever network interface is configured.
+#if (defined(USE_ESP8266) || defined(USE_RP2040)) && \
+    ((defined(USE_WIFI) && defined(USE_WIFI_IP_STATE_LISTENERS)) || \
+     (defined(USE_ETHERNET) && defined(USE_ETHERNET_IP_STATE_LISTENERS)))
+#include "esphome/components/network/ip_address.h"
+#define USE_MDNS_EVENT_DRIVEN_POLLING
+#if defined(USE_WIFI) && defined(USE_WIFI_IP_STATE_LISTENERS)
+#include "esphome/components/wifi/wifi_component.h"
+#define USE_MDNS_WIFI_LISTENER
+#endif
+#if defined(USE_ETHERNET) && defined(USE_ETHERNET_IP_STATE_LISTENERS)
+#include "esphome/components/ethernet/ethernet_component.h"
+#define USE_MDNS_ETHERNET_LISTENER
+#endif
+#endif
 
 namespace esphome::mdns {
 
@@ -40,33 +56,43 @@ struct MDNSService {
   FixedVector<MDNSTXTRecord> txt_records;
 };
 
-class MDNSComponent final : public Component {
+class MDNSComponent final : public Component
+#ifdef USE_MDNS_WIFI_LISTENER
+    ,
+                            public wifi::WiFiIPStateListener
+#endif
+#ifdef USE_MDNS_ETHERNET_LISTENER
+    ,
+                            public ethernet::EthernetIPStateListener
+#endif
+{
  public:
   void setup() override;
   void dump_config() override;
 
-  // Polling interval for MDNS.update() on platforms that require it (ESP8266, RP2040).
-  //
-  // On these platforms, MDNS.update() calls _process(true) which only manages timer-driven
-  // state machines (probe/announce timeouts and service query cache TTLs). Incoming mDNS
-  // packets are handled independently via the lwIP onRx UDP callback and are NOT affected
-  // by how often update() is called.
-  //
-  // The shortest internal timer is the 250ms probe interval (RFC 6762 Section 8.1).
-  // Announcement intervals are 1000ms and cache TTL checks are on the order of seconds
-  // to minutes. A 50ms polling interval provides sufficient resolution for all timers
-  // while completely removing mDNS from the per-iteration loop list.
-  //
-  // In steady state (after the ~8 second boot probe/announce phase completes), update()
-  // checks timers that are set to never expire, making every call pure overhead.
-  //
-  // Tasmota uses a 50ms main loop cycle with mDNS working correctly, confirming this
-  // interval is safe in production.
-  //
-  // By using set_interval() instead of overriding loop(), the component is excluded from
-  // the main loop list via has_overridden_loop(), eliminating all per-iteration overhead
-  // including virtual dispatch.
+  /// Size of buffer required for config hash hex string (8 hex chars + null terminator)
+  static constexpr size_t CONFIG_HASH_STR_SIZE = format_hex_size(sizeof(uint32_t));
+
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+  // LEAmDNS has meaningful work only during the probe+announce phase (3×250ms probes +
+  // 8×1000ms announces, ~9s). Afterwards every internal timer is resetToNeverExpires()
+  // and update() becomes pure overhead. We arm a bounded polling window from IP state
+  // listener events so update() runs only during that phase.
   static constexpr uint32_t MDNS_UPDATE_INTERVAL_MS = 50;
+  // Must exceed LEAmDNS's longest restart-to-announce-complete path:
+  //   MDNS_PROBE_DELAY (250ms) × MDNS_PROBE_COUNT (3) = 750ms probing
+  // + MDNS_ANNOUNCE_DELAY (1000ms) × MDNS_ANNOUNCE_COUNT (8) = 8000ms announcing
+  // + rand() % MDNS_PROBE_DELAY jitter on first probe (0–250ms)
+  // + debounced schedule_function() hop when statusChangeCB fires on ESP8266
+  // ≈ 9s nominal. 15s gives ~6s margin to absorb main-loop blocking (long
+  // component setup, WiFi scan, flash writes) that could stretch the deadlines
+  // between our polls. If LEAmDNS ever extends its phase (upstream library
+  // update) this constant needs to grow. Constants defined in LEAmDNS_Priv.h
+  // (ESP8266 core 3.1.2 / arduino-pico 5.5.1).
+  static constexpr uint32_t MDNS_POLL_WINDOW_MS = 15000;
+  static constexpr uint32_t MDNS_POLL_ID = 0;
+  static constexpr uint32_t MDNS_POLL_STOP_ID = 1;
+#endif
   float get_setup_priority() const override { return setup_priority::AFTER_CONNECTION; }
 
 #ifdef USE_MDNS_EXTRA_SERVICES
@@ -87,34 +113,21 @@ class MDNSComponent final : public Component {
   }
 #endif
 
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+  void on_ip_state(const network::IPAddresses &ips, const network::IPAddress &dns1,
+                   const network::IPAddress &dns2) override;
+#endif
+
  protected:
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+  /// Arm a fresh MDNS_POLL_WINDOW_MS polling window. Idempotent — re-arming replaces
+  /// the previous window via the scheduler's atomic cancel-and-add on matching IDs.
+  void start_polling_window_();
+#endif
   /// Helper to set up services and MAC buffers, then call platform-specific registration
   using PlatformRegisterFn = void (*)(MDNSComponent *, StaticVector<MDNSService, MDNS_SERVICE_COUNT> &);
 
-  void setup_buffers_and_register_(PlatformRegisterFn platform_register) {
-#ifdef USE_MDNS_STORE_SERVICES
-    auto &services = this->services_;
-#else
-    StaticVector<MDNSService, MDNS_SERVICE_COUNT> services_storage;
-    auto &services = services_storage;
-#endif
-
-#ifdef USE_API
-#ifdef USE_MDNS_STORE_SERVICES
-    get_mac_address_into_buffer(this->mac_address_);
-    char *mac_ptr = this->mac_address_;
-#else
-    char mac_address[MAC_ADDRESS_BUFFER_SIZE];
-    get_mac_address_into_buffer(mac_address);
-    char *mac_ptr = mac_address;
-#endif
-#else
-    char *mac_ptr = nullptr;
-#endif
-
-    this->compile_records_(services, mac_ptr);
-    platform_register(this, services);
-  }
+  void setup_buffers_and_register_(PlatformRegisterFn platform_register);
 
 #ifdef USE_MDNS_DYNAMIC_TXT
   /// Storage for runtime-generated TXT values from user lambdas
@@ -126,15 +139,18 @@ class MDNSComponent final : public Component {
 #if defined(USE_API) && defined(USE_MDNS_STORE_SERVICES)
   /// Fixed buffer for MAC address (only needed when services are stored)
   char mac_address_[MAC_ADDRESS_BUFFER_SIZE];
+  /// Fixed buffer for config hash hex string (only needed when services are stored)
+  char config_hash_str_[CONFIG_HASH_STR_SIZE];
 #endif
 #ifdef USE_MDNS_STORE_SERVICES
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services_{};
 #endif
-#ifdef USE_RP2040
-  bool was_connected_{false};
+#if defined(USE_RP2040) && defined(USE_MDNS_EVENT_DRIVEN_POLLING)
+  // RP2040 defers MDNS.begin() until the first IP-up event; this tracks that.
   bool initialized_{false};
 #endif
-  void compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services, char *mac_address_buf);
+  void compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services, char *mac_address_buf,
+                        char *config_hash_buf);
 };
 
 }  // namespace esphome::mdns
diff --git a/esphome/components/mdns/mdns_esp8266.cpp b/esphome/components/mdns/mdns_esp8266.cpp
index 70c614f8d3..f6d5786675 100644
--- a/esphome/components/mdns/mdns_esp8266.cpp
+++ b/esphome/components/mdns/mdns_esp8266.cpp
@@ -8,6 +8,8 @@
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
+// wifi_component.h is pulled in transitively by mdns_component.h when
+// USE_MDNS_WIFI_LISTENER is defined.
 
 namespace esphome::mdns {
 
@@ -36,15 +38,36 @@ static void register_esp8266(MDNSComponent *, StaticVector<MDNSService, MDNS_SER
   }
 }
 
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+void MDNSComponent::start_polling_window_() {
+  // uint32_t-ID set_interval/set_timeout already does atomic cancel-and-add.
+  this->set_interval(MDNS_POLL_ID, MDNS_UPDATE_INTERVAL_MS, []() { MDNS.update(); });
+  this->set_timeout(MDNS_POLL_STOP_ID, MDNS_POLL_WINDOW_MS, [this]() { this->cancel_interval(MDNS_POLL_ID); });
+}
+#endif
+
 void MDNSComponent::setup() {
   this->setup_buffers_and_register_(register_esp8266);
-  // Schedule MDNS.update() via set_interval() instead of overriding loop().
-  // This removes the component from the per-iteration loop list entirely,
-  // eliminating virtual dispatch overhead on every main loop cycle.
-  // See MDNS_UPDATE_INTERVAL_MS comment in mdns_component.h for safety analysis.
-  this->set_interval(MDNS_UPDATE_INTERVAL_MS, []() { MDNS.update(); });
+#ifdef USE_MDNS_WIFI_LISTENER
+  // LEAmDNS's own LwipIntf::statusChangeCB drives _restart() on netif changes; we just
+  // arm the window around the initial probe/announce and each reconnect. Unconditional
+  // here is safe: setup_priority::AFTER_CONNECTION guarantees the network is up.
+  wifi::global_wifi_component->add_ip_state_listener(this);
+  this->start_polling_window_();
+#endif
 }
 
+#ifdef USE_MDNS_WIFI_LISTENER
+void MDNSComponent::on_ip_state(const network::IPAddresses &ips, const network::IPAddress &,
+                                const network::IPAddress &) {
+  // IP listener only fires on acquisition (not loss), so any notification is a fresh
+  // IP worth re-arming for. start_polling_window_() is idempotent.
+  if (ips[0].is_set()) {
+    this->start_polling_window_();
+  }
+}
+#endif
+
 void MDNSComponent::on_shutdown() {
   MDNS.close();
   delay(10);
diff --git a/esphome/components/mdns/mdns_host.cpp b/esphome/components/mdns/mdns_host.cpp
index 4d902319b8..1e66a10df0 100644
--- a/esphome/components/mdns/mdns_host.cpp
+++ b/esphome/components/mdns/mdns_host.cpp
@@ -3,6 +3,8 @@
 
 #include "esphome/components/network/ip_address.h"
 #include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
@@ -13,10 +15,13 @@ void MDNSComponent::setup() {
 #ifdef USE_API
   get_mac_address_into_buffer(this->mac_address_);
   char *mac_ptr = this->mac_address_;
+  format_hex_to(this->config_hash_str_, App.get_config_hash());
+  char *cfg_ptr = this->config_hash_str_;
 #else
   char *mac_ptr = nullptr;
+  char *cfg_ptr = nullptr;
 #endif
-  this->compile_records_(this->services_, mac_ptr);
+  this->compile_records_(this->services_, mac_ptr, cfg_ptr);
 #endif
   // Host platform doesn't have actual mDNS implementation
 }
diff --git a/esphome/components/mdns/mdns_rp2040.cpp b/esphome/components/mdns/mdns_rp2040.cpp
index 64b603030c..f5848893a3 100644
--- a/esphome/components/mdns/mdns_rp2040.cpp
+++ b/esphome/components/mdns/mdns_rp2040.cpp
@@ -6,9 +6,10 @@
 #include "esphome/core/application.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
+// wifi_component.h / ethernet_component.h are pulled in transitively by
+// mdns_component.h when their respective listener defines are active.
 
 // Arduino-Pico's PolledTimeout.h (pulled in by ESP8266mDNS.h) redefines IRAM_ATTR to empty.
-// Save and restore our definition around the include to avoid a redefinition warning.
 #pragma push_macro("IRAM_ATTR")
 #undef IRAM_ATTR
 #include <ESP8266mDNS.h>
@@ -20,10 +21,7 @@ static void register_rp2040(MDNSComponent *, StaticVector<MDNSService, MDNS_SERV
   MDNS.begin(App.get_name().c_str());
 
   for (const auto &service : services) {
-    // Strip the leading underscore from the proto and service_type. While it is
-    // part of the wire protocol to have an underscore, and for example ESP-IDF
-    // expects the underscore to be there, the ESP8266 implementation always adds
-    // the underscore itself.
+    // ESP8266mDNS always adds the leading underscore itself, so strip it here.
     auto *proto = MDNS_STR_ARG(service.proto);
     while (*proto == '_') {
       proto++;
@@ -40,34 +38,58 @@ static void register_rp2040(MDNSComponent *, StaticVector<MDNSService, MDNS_SERV
   }
 }
 
-void MDNSComponent::setup() {
-  // RP2040's LEAmDNS library registers a LwipIntf::stateUpCB() callback to restart
-  // mDNS when the network interface reconnects. However, stateUpCB() is stubbed out
-  // in arduino-pico's LwipIntfCB.cpp because the original ESP8266 implementation used
-  // schedule_function() which doesn't exist in arduino-pico, and the callback can't
-  // safely run directly since netif status callbacks fire from IRQ context
-  // (PICO_CYW43_ARCH_THREADSAFE_BACKGROUND) while _restart() allocates UDP sockets.
-  //
-  // Workaround: defer MDNS.begin() and service registration until the network is
-  // connected (has an IP), then call notifyAPChange() on subsequent reconnects to
-  // restart mDNS probing and announcing — all from main loop context so it's
-  // thread-safe.
-  this->set_interval(MDNS_UPDATE_INTERVAL_MS, [this]() {
-    bool connected = network::is_connected();
-    if (connected && !this->was_connected_) {
-      if (!this->initialized_) {
-        this->setup_buffers_and_register_(register_rp2040);
-        this->initialized_ = true;
-      } else {
-        MDNS.notifyAPChange();
-      }
-    }
-    this->was_connected_ = connected;
-    if (this->initialized_) {
-      MDNS.update();
-    }
-  });
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+void MDNSComponent::start_polling_window_() {
+  // uint32_t-ID set_interval/set_timeout already does atomic cancel-and-add.
+  this->set_interval(MDNS_POLL_ID, MDNS_UPDATE_INTERVAL_MS, []() { MDNS.update(); });
+  this->set_timeout(MDNS_POLL_STOP_ID, MDNS_POLL_WINDOW_MS, [this]() { this->cancel_interval(MDNS_POLL_ID); });
 }
+#endif
+
+void MDNSComponent::setup() {
+  // arduino-pico stubs out LwipIntf::stateUpCB (the netif status callback LEAmDNS uses
+  // on ESP8266 for auto-restart), so we must drive begin()/notifyAPChange() from our
+  // own IP state listener. Both WiFi and Ethernet have the same listener signature —
+  // one on_ip_state() override serves both.
+#ifdef USE_MDNS_WIFI_LISTENER
+  wifi::global_wifi_component->add_ip_state_listener(this);
+  // AFTER_CONNECTION priority means the network may already be up; the listener only
+  // fires on subsequent changes, so seed the current state.
+  {
+    const auto ips = wifi::global_wifi_component->wifi_sta_ip_addresses();
+    if (ips[0].is_set()) {
+      this->on_ip_state(ips, wifi::global_wifi_component->get_dns_address(0),
+                        wifi::global_wifi_component->get_dns_address(1));
+    }
+  }
+#endif
+#ifdef USE_MDNS_ETHERNET_LISTENER
+  ethernet::global_eth_component->add_ip_state_listener(this);
+  if (ethernet::global_eth_component->is_connected()) {
+    const auto ips = ethernet::global_eth_component->get_ip_addresses();
+    if (ips[0].is_set()) {
+      this->on_ip_state(ips, network::IPAddress{}, network::IPAddress{});
+    }
+  }
+#endif
+}
+
+#ifdef USE_MDNS_EVENT_DRIVEN_POLLING
+void MDNSComponent::on_ip_state(const network::IPAddresses &ips, const network::IPAddress &,
+                                const network::IPAddress &) {
+  // Listener only fires on IP acquisition (not loss); every event is a fresh IP.
+  if (!ips[0].is_set()) {
+    return;
+  }
+  if (!this->initialized_) {
+    this->setup_buffers_and_register_(register_rp2040);
+    this->initialized_ = true;
+  } else {
+    MDNS.notifyAPChange();
+  }
+  this->start_polling_window_();
+}
+#endif
 
 void MDNSComponent::on_shutdown() {
   MDNS.close();
diff --git a/esphome/components/mixer/speaker/mixer_speaker.cpp b/esphome/components/mixer/speaker/mixer_speaker.cpp
index 741239a2dd..0d16bce330 100644
--- a/esphome/components/mixer/speaker/mixer_speaker.cpp
+++ b/esphome/components/mixer/speaker/mixer_speaker.cpp
@@ -588,6 +588,7 @@ void MixerSpeaker::mix_audio_samples(const int16_t *primary_buffer, audio::Audio
   }
 }
 
+// NOLINTBEGIN(bugprone-unchecked-optional-access) -- audio_stream_info_ always set before this task is created
 void MixerSpeaker::audio_mixer_task(void *params) {
   MixerSpeaker *this_mixer = static_cast<MixerSpeaker *>(params);
 
@@ -764,6 +765,7 @@ void MixerSpeaker::audio_mixer_task(void *params) {
 
   vTaskSuspend(nullptr);  // Suspend this task indefinitely until the loop method deletes it
 }
+// NOLINTEND(bugprone-unchecked-optional-access)
 
 }  // namespace esphome::mixer_speaker
 
diff --git a/esphome/components/modbus_controller/__init__.py b/esphome/components/modbus_controller/__init__.py
index 2af58a96be..67e5757397 100644
--- a/esphome/components/modbus_controller/__init__.py
+++ b/esphome/components/modbus_controller/__init__.py
@@ -3,11 +3,8 @@ import binascii
 from esphome import automation
 import esphome.codegen as cg
 from esphome.components import modbus
-from esphome.components.const import CONF_ENABLED
 from esphome.components.modbus.helpers import (
-    CPP_TYPE_REGISTER_MAP,
     MODBUS_REGISTER_TYPE,
-    SENSOR_VALUE_TYPE,
     TYPE_REGISTER_MAP,
     ModbusRegisterType,
 )
@@ -29,11 +26,10 @@ from .const import (
     CONF_ON_OFFLINE,
     CONF_ON_ONLINE,
     CONF_REGISTER_COUNT,
-    CONF_REGISTER_LAST_ADDRESS,
     CONF_REGISTER_TYPE,
-    CONF_REGISTER_VALUE,
     CONF_RESPONSE_SIZE,
     CONF_SERVER_COURTESY_RESPONSE,
+    CONF_SERVER_REGISTERS,
     CONF_SKIP_UPDATES,
     CONF_VALUE_TYPE,
 )
@@ -42,9 +38,6 @@ CODEOWNERS = ["@martgras"]
 
 AUTO_LOAD = ["modbus"]
 
-CONF_READ_LAMBDA = "read_lambda"
-CONF_WRITE_LAMBDA = "write_lambda"
-CONF_SERVER_REGISTERS = "server_registers"
 MULTI_CONF = True
 
 modbus_controller_ns = cg.esphome_ns.namespace("modbus_controller")
@@ -53,30 +46,9 @@ ModbusController = modbus_controller_ns.class_(
 )
 
 SensorItem = modbus_controller_ns.struct("SensorItem")
-ServerCourtesyResponse = modbus_controller_ns.struct("ServerCourtesyResponse")
-ServerRegister = modbus_controller_ns.struct("ServerRegister")
 
 _LOGGER = logging.getLogger(__name__)
 
-SERVER_COURTESY_RESPONSE_SCHEMA = cv.Schema(
-    {
-        cv.Optional(CONF_ENABLED, default=False): cv.boolean,
-        cv.Optional(CONF_REGISTER_LAST_ADDRESS, default=0xFFFF): cv.hex_uint16_t,
-        cv.Optional(CONF_REGISTER_VALUE, default=0): cv.hex_uint16_t,
-    }
-)
-
-ModbusServerRegisterSchema = cv.Schema(
-    {
-        cv.GenerateID(): cv.declare_id(ServerRegister),
-        cv.Required(CONF_ADDRESS): cv.positive_int,
-        cv.Optional(CONF_VALUE_TYPE, default="U_WORD"): cv.enum(SENSOR_VALUE_TYPE),
-        cv.Required(CONF_READ_LAMBDA): cv.returning_lambda,
-        cv.Optional(CONF_WRITE_LAMBDA): cv.returning_lambda,
-    }
-)
-
-
 CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
@@ -85,12 +57,16 @@ CONFIG_SCHEMA = cv.All(
             cv.Optional(
                 CONF_COMMAND_THROTTLE, default="0ms"
             ): cv.positive_time_period_milliseconds,
-            cv.Optional(CONF_SERVER_COURTESY_RESPONSE): SERVER_COURTESY_RESPONSE_SCHEMA,
+            cv.Optional(CONF_SERVER_COURTESY_RESPONSE): cv.invalid(
+                "This option has been removed. Use modbus_server component instead: https://esphome.io/components/modbus_server/"
+            ),
             cv.Optional(CONF_MAX_CMD_RETRIES, default=4): cv.positive_int,
             cv.Optional(CONF_OFFLINE_SKIP_UPDATES, default=0): cv.positive_int,
             cv.Optional(
                 CONF_SERVER_REGISTERS,
-            ): cv.ensure_list(ModbusServerRegisterSchema),
+            ): cv.invalid(
+                "This option has been removed. Use modbus_server component instead: https://esphome.io/components/modbus_server/"
+            ),
             cv.Optional(CONF_ON_COMMAND_SENT): automation.validate_automation({}),
             cv.Optional(CONF_ON_ONLINE): automation.validate_automation({}),
             cv.Optional(CONF_ON_OFFLINE): automation.validate_automation({}),
@@ -142,11 +118,9 @@ def validate_modbus_register(config):
 
 
 def _final_validate(config):
-    if CONF_SERVER_COURTESY_RESPONSE in config or CONF_SERVER_REGISTERS in config:
-        return modbus.final_validate_modbus_device("modbus_controller", role="server")(
-            config
-        )
-    return config
+    return modbus.final_validate_modbus_device("modbus_controller", role="client")(
+        config
+    )
 
 
 FINAL_VALIDATE_SCHEMA = _final_validate
@@ -228,53 +202,8 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     cg.add(var.set_allow_duplicate_commands(config[CONF_ALLOW_DUPLICATE_COMMANDS]))
     cg.add(var.set_command_throttle(config[CONF_COMMAND_THROTTLE]))
-    if server_courtesy_response := config.get(CONF_SERVER_COURTESY_RESPONSE):
-        cg.add(
-            var.set_server_courtesy_response(
-                cg.StructInitializer(
-                    ServerCourtesyResponse,
-                    ("enabled", server_courtesy_response[CONF_ENABLED]),
-                    (
-                        "register_last_address",
-                        server_courtesy_response[CONF_REGISTER_LAST_ADDRESS],
-                    ),
-                    ("register_value", server_courtesy_response[CONF_REGISTER_VALUE]),
-                )
-            )
-        )
     cg.add(var.set_max_cmd_retries(config[CONF_MAX_CMD_RETRIES]))
     cg.add(var.set_offline_skip_updates(config[CONF_OFFLINE_SKIP_UPDATES]))
-    if CONF_SERVER_REGISTERS in config:
-        for server_register in config[CONF_SERVER_REGISTERS]:
-            server_register_var = cg.new_Pvariable(
-                server_register[CONF_ID],
-                server_register[CONF_ADDRESS],
-                server_register[CONF_VALUE_TYPE],
-                TYPE_REGISTER_MAP[server_register[CONF_VALUE_TYPE]],
-            )
-            cpp_type = CPP_TYPE_REGISTER_MAP[server_register[CONF_VALUE_TYPE]]
-            cg.add(
-                server_register_var.set_read_lambda(
-                    cg.TemplateArguments(cpp_type),
-                    await cg.process_lambda(
-                        server_register[CONF_READ_LAMBDA],
-                        [(cg.uint16, "address")],
-                        return_type=cpp_type,
-                    ),
-                )
-            )
-            if CONF_WRITE_LAMBDA in server_register:
-                cg.add(
-                    server_register_var.set_write_lambda(
-                        cg.TemplateArguments(cpp_type),
-                        await cg.process_lambda(
-                            server_register[CONF_WRITE_LAMBDA],
-                            parameters=[(cg.uint16, "address"), (cpp_type, "x")],
-                            return_type=cg.bool_,
-                        ),
-                    )
-                )
-            cg.add(var.add_server_register(server_register_var))
     await register_modbus_device(var, config)
     await automation.build_callback_automations(var, config, _CALLBACK_AUTOMATIONS)
 
diff --git a/esphome/components/modbus_controller/const.py b/esphome/components/modbus_controller/const.py
index c689d84576..0149a3cc49 100644
--- a/esphome/components/modbus_controller/const.py
+++ b/esphome/components/modbus_controller/const.py
@@ -18,6 +18,7 @@ CONF_REGISTER_TYPE = "register_type"
 CONF_REGISTER_VALUE = "register_value"
 CONF_RESPONSE_SIZE = "response_size"
 CONF_SERVER_COURTESY_RESPONSE = "server_courtesy_response"
+CONF_SERVER_REGISTERS = "server_registers"
 CONF_SKIP_UPDATES = "skip_updates"
 CONF_USE_WRITE_MULTIPLE = "use_write_multiple"
 CONF_VALUE_TYPE = "value_type"
diff --git a/esphome/components/modbus_controller/modbus_controller.cpp b/esphome/components/modbus_controller/modbus_controller.cpp
index 5c3b39c954..dabed7136b 100644
--- a/esphome/components/modbus_controller/modbus_controller.cpp
+++ b/esphome/components/modbus_controller/modbus_controller.cpp
@@ -112,167 +112,6 @@ void ModbusController::on_modbus_error(uint8_t function_code, uint8_t exception_
   }
 }
 
-void ModbusController::on_modbus_read_registers(uint8_t function_code, uint16_t start_address,
-                                                uint16_t number_of_registers) {
-  ESP_LOGD(TAG,
-           "Received read holding/input registers for device 0x%X. FC: 0x%X. Start address: 0x%X. Number of registers: "
-           "0x%X.",
-           this->address_, function_code, start_address, number_of_registers);
-
-  if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_READ) {
-    ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
-    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
-    return;
-  }
-
-  std::vector<uint16_t> sixteen_bit_response;
-  for (uint16_t current_address = start_address; current_address < start_address + number_of_registers;) {
-    bool found = false;
-    for (auto *server_register : this->server_registers_) {
-      if (server_register->address == current_address) {
-        if (!server_register->read_lambda) {
-          break;
-        }
-        int64_t value = server_register->read_lambda();
-        ESP_LOGD(TAG, "Matched register. Address: 0x%02X. Value type: %zu. Register count: %u. Value: %s.",
-                 server_register->address, static_cast<size_t>(server_register->value_type),
-                 server_register->register_count, server_register->format_value(value).c_str());
-
-        std::vector<uint16_t> payload;
-        payload.reserve(server_register->register_count * 2);
-        modbus::helpers::number_to_payload(payload, value, server_register->value_type);
-        sixteen_bit_response.insert(sixteen_bit_response.end(), payload.cbegin(), payload.cend());
-        current_address += server_register->register_count;
-        found = true;
-        break;
-      }
-    }
-
-    if (!found) {
-      if (this->server_courtesy_response_.enabled &&
-          (current_address <= this->server_courtesy_response_.register_last_address)) {
-        ESP_LOGD(TAG,
-                 "Could not match any register to address 0x%02X, but default allowed. "
-                 "Returning default value: %d.",
-                 current_address, this->server_courtesy_response_.register_value);
-        sixteen_bit_response.push_back(this->server_courtesy_response_.register_value);
-        current_address += 1;  // Just increment by 1, as the default response is a single register
-      } else {
-        ESP_LOGW(TAG,
-                 "Could not match any register to address 0x%02X and default not allowed. Sending exception response.",
-                 current_address);
-        this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
-        return;
-      }
-    }
-  }
-
-  std::vector<uint8_t> response;
-  for (auto v : sixteen_bit_response) {
-    auto decoded_value = decode_value(v);
-    response.push_back(decoded_value[0]);
-    response.push_back(decoded_value[1]);
-  }
-
-  this->send(function_code, start_address, number_of_registers, response.size(), response.data());
-}
-
-void ModbusController::on_modbus_write_registers(uint8_t function_code, const std::vector<uint8_t> &data) {
-  uint16_t number_of_registers;
-  uint16_t payload_offset;
-
-  if (function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
-    if (data.size() < 5) {
-      ESP_LOGW(TAG, "Write multiple registers data too short (%zu bytes)", data.size());
-      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
-      return;
-    }
-    number_of_registers = uint16_t(data[3]) | (uint16_t(data[2]) << 8);
-    if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_WRITE) {
-      ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
-      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
-      return;
-    }
-    uint16_t payload_size = data[4];
-    if (payload_size != number_of_registers * 2) {
-      ESP_LOGW(TAG, "Payload size of %d bytes is not 2 times the number of registers (%d). Sending exception response.",
-               payload_size, number_of_registers);
-      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
-      return;
-    }
-    if (data.size() < 5 + payload_size) {
-      ESP_LOGW(TAG, "Write multiple registers payload truncated (%zu bytes, expected %u)", data.size(),
-               5 + payload_size);
-      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
-      return;
-    }
-    payload_offset = 5;
-  } else if (function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER) {
-    if (data.size() < 4) {
-      ESP_LOGW(TAG, "Write single register data too short (%zu bytes)", data.size());
-      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
-      return;
-    }
-    number_of_registers = 1;
-    payload_offset = 2;
-  } else {
-    ESP_LOGW(TAG, "Invalid function code 0x%X. Sending exception response.", function_code);
-    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
-    return;
-  }
-
-  uint16_t start_address = uint16_t(data[1]) | (uint16_t(data[0]) << 8);
-  ESP_LOGD(TAG,
-           "Received write holding registers for device 0x%X. FC: 0x%X. Start address: 0x%X. Number of registers: "
-           "0x%X.",
-           this->address_, function_code, start_address, number_of_registers);
-
-  auto for_each_register = [this, start_address, number_of_registers, payload_offset](
-                               const std::function<bool(ServerRegister *, uint16_t offset)> &callback) -> bool {
-    uint16_t offset = payload_offset;
-    for (uint16_t current_address = start_address; current_address < start_address + number_of_registers;) {
-      bool ok = false;
-      for (auto *server_register : this->server_registers_) {
-        if (server_register->address == current_address) {
-          ok = callback(server_register, offset);
-          current_address += server_register->register_count;
-          offset += server_register->register_count * sizeof(uint16_t);
-          break;
-        }
-      }
-
-      if (!ok) {
-        return false;
-      }
-    }
-    return true;
-  };
-
-  // check all registers are writable before writing to any of them:
-  if (!for_each_register([](ServerRegister *server_register, uint16_t offset) -> bool {
-        return server_register->write_lambda != nullptr;
-      })) {
-    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
-    return;
-  }
-
-  // Actually write to the registers:
-  if (!for_each_register([&data](ServerRegister *server_register, uint16_t offset) {
-        int64_t number = modbus::helpers::payload_to_number(data, server_register->value_type, offset, 0xFFFFFFFF);
-        return server_register->write_lambda(number);
-      })) {
-    this->send_error(function_code, ModbusExceptionCode::SERVICE_DEVICE_FAILURE);
-    return;
-  }
-
-  std::vector<uint8_t> response;
-  response.reserve(6);
-  response.push_back(this->address_);
-  response.push_back(function_code);
-  response.insert(response.end(), data.begin(), data.begin() + 4);
-  this->send_raw(response);
-}
-
 SensorSet ModbusController::find_sensors_(ModbusRegisterType register_type, uint16_t start_address) const {
   auto reg_it = std::find_if(
       std::begin(this->register_ranges_), std::end(this->register_ranges_),
@@ -472,14 +311,8 @@ void ModbusController::dump_config() {
                 "ModbusController:\n"
                 "  Address: 0x%02X\n"
                 "  Max Command Retries: %d\n"
-                "  Offline Skip Updates: %d\n"
-                "  Server Courtesy Response:\n"
-                "    Enabled: %s\n"
-                "    Register Last Address: 0x%02X\n"
-                "    Register Value: %d",
-                this->address_, this->max_cmd_retries_, this->offline_skip_updates_,
-                this->server_courtesy_response_.enabled ? "true" : "false",
-                this->server_courtesy_response_.register_last_address, this->server_courtesy_response_.register_value);
+                "  Offline Skip Updates: %d\n",
+                this->address_, this->max_cmd_retries_, this->offline_skip_updates_);
 
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
   ESP_LOGCONFIG(TAG, "sensormap");
@@ -493,11 +326,6 @@ void ModbusController::dump_config() {
     ESP_LOGCONFIG(TAG, "  Range type=%u start=0x%X count=%d skip_updates=%d", static_cast<uint8_t>(it.register_type),
                   it.start_address, it.register_count, it.skip_updates);
   }
-  ESP_LOGCONFIG(TAG, "server registers");
-  for (auto &r : this->server_registers_) {
-    ESP_LOGCONFIG(TAG, "  Address=0x%02X value_type=%u register_count=%u", r->address,
-                  static_cast<uint8_t>(r->value_type), r->register_count);
-  }
 #endif
 }
 
diff --git a/esphome/components/modbus_controller/modbus_controller.h b/esphome/components/modbus_controller/modbus_controller.h
index 6c6c748b73..40139f055b 100644
--- a/esphome/components/modbus_controller/modbus_controller.h
+++ b/esphome/components/modbus_controller/modbus_controller.h
@@ -120,82 +120,6 @@ class SensorItem {
   bool force_new_range{false};
 };
 
-struct ServerCourtesyResponse {
-  bool enabled{false};
-  uint16_t register_last_address{0xFFFF};
-  uint16_t register_value{0};
-};
-
-class ServerRegister {
-  using ReadLambda = std::function<int64_t()>;
-  using WriteLambda = std::function<bool(int64_t value)>;
-
- public:
-  ServerRegister(uint16_t address, SensorValueType value_type, uint8_t register_count) {
-    this->address = address;
-    this->value_type = value_type;
-    this->register_count = register_count;
-  }
-
-  template<typename T> void set_read_lambda(const std::function<T(uint16_t address)> &&user_read_lambda) {
-    this->read_lambda = [this, user_read_lambda]() -> int64_t {
-      T user_value = user_read_lambda(this->address);
-      if constexpr (std::is_same_v<T, float>) {
-        return bit_cast<uint32_t>(user_value);
-      } else {
-        return static_cast<int64_t>(user_value);
-      }
-    };
-  }
-
-  template<typename T>
-  void set_write_lambda(const std::function<bool(uint16_t address, const T v)> &&user_write_lambda) {
-    this->write_lambda = [this, user_write_lambda](int64_t number) {
-      if constexpr (std::is_same_v<T, float>) {
-        float float_value = bit_cast<float>(static_cast<uint32_t>(number));
-        return user_write_lambda(this->address, float_value);
-      }
-      return user_write_lambda(this->address, static_cast<T>(number));
-    };
-  }
-
-  // Formats a raw value into a string representation based on the value type for debugging
-  std::string format_value(int64_t value) const {
-    // max 44: float with %.1f can be up to 42 chars (3.4e38 → 39 integer digits + sign + decimal + 1 digit)
-    // plus null terminator = 43, rounded to 44 for 4-byte alignment
-    char buf[44];
-    switch (this->value_type) {
-      case SensorValueType::U_WORD:
-      case SensorValueType::U_DWORD:
-      case SensorValueType::U_DWORD_R:
-      case SensorValueType::U_QWORD:
-      case SensorValueType::U_QWORD_R:
-        buf_append_printf(buf, sizeof(buf), 0, "%" PRIu64, static_cast<uint64_t>(value));
-        return buf;
-      case SensorValueType::S_WORD:
-      case SensorValueType::S_DWORD:
-      case SensorValueType::S_DWORD_R:
-      case SensorValueType::S_QWORD:
-      case SensorValueType::S_QWORD_R:
-        buf_append_printf(buf, sizeof(buf), 0, "%" PRId64, value);
-        return buf;
-      case SensorValueType::FP32_R:
-      case SensorValueType::FP32:
-        buf_append_printf(buf, sizeof(buf), 0, "%.1f", bit_cast<float>(static_cast<uint32_t>(value)));
-        return buf;
-      default:
-        buf_append_printf(buf, sizeof(buf), 0, "%" PRId64, value);
-        return buf;
-    }
-  }
-
-  uint16_t address{0};
-  SensorValueType value_type{SensorValueType::RAW};
-  uint8_t register_count{0};
-  ReadLambda read_lambda;
-  WriteLambda write_lambda;
-};
-
 // ModbusController::create_register_ranges_ tries to optimize register range
 // for this the sensors must be ordered by register_type, start_address and bitmask
 class SensorItemsComparator {
@@ -367,16 +291,10 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   void queue_command(const ModbusCommandItem &command);
   /// Registers a sensor with the controller. Called by esphomes code generator
   void add_sensor_item(SensorItem *item) { sensorset_.insert(item); }
-  /// Registers a server register with the controller. Called by esphomes code generator
-  void add_server_register(ServerRegister *server_register) { server_registers_.push_back(server_register); }
   /// called when a modbus response was parsed without errors
   void on_modbus_data(const std::vector<uint8_t> &data) override;
   /// called when a modbus error response was received
   void on_modbus_error(uint8_t function_code, uint8_t exception_code) override;
-  /// called when a modbus request (function code 0x03 or 0x04) was parsed without errors
-  void on_modbus_read_registers(uint8_t function_code, uint16_t start_address, uint16_t number_of_registers) final;
-  /// called when a modbus request (function code 0x06 or 0x10) was parsed without errors
-  void on_modbus_write_registers(uint8_t function_code, const std::vector<uint8_t> &data) final;
   /// default delegate called by process_modbus_data when a response has retrieved from the incoming queue
   void on_register_data(ModbusRegisterType register_type, uint16_t start_address, const std::vector<uint8_t> &data);
   /// default delegate called by process_modbus_data when a response for a write response has retrieved from the
@@ -413,12 +331,6 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   void set_max_cmd_retries(uint8_t max_cmd_retries) { this->max_cmd_retries_ = max_cmd_retries; }
   /// get how many times a command will be (re)sent if no response is received
   uint8_t get_max_cmd_retries() { return this->max_cmd_retries_; }
-  /// Called by esphome generated code to set the server courtesy response object
-  void set_server_courtesy_response(const ServerCourtesyResponse &server_courtesy_response) {
-    this->server_courtesy_response_ = server_courtesy_response;
-  }
-  /// Get the server courtesy response object
-  ServerCourtesyResponse get_server_courtesy_response() const { return this->server_courtesy_response_; }
 
  protected:
   /// parse sensormap_ and create range of sequential addresses
@@ -435,8 +347,6 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   void dump_sensors_();
   /// Collection of all sensors for this component
   SensorSet sensorset_;
-  /// Collection of all server registers for this component
-  std::vector<ServerRegister *> server_registers_{};
   /// Continuous range of modbus registers
   std::vector<RegisterRange> register_ranges_{};
   /// Hold the pending requests to be sent
@@ -461,9 +371,6 @@ class ModbusController : public PollingComponent, public modbus::ModbusDevice {
   CallbackManager<void(int, int)> online_callback_{};
   /// Server offline callback
   CallbackManager<void(int, int)> offline_callback_{};
-  /// Server courtesy response
-  ServerCourtesyResponse server_courtesy_response_{
-      .enabled = false, .register_last_address = 0xFFFF, .register_value = 0};
 };
 
 /** Convert vector<uint8_t> response payload to float.
diff --git a/esphome/components/modbus_server/__init__.py b/esphome/components/modbus_server/__init__.py
new file mode 100644
index 0000000000..5182bc05d1
--- /dev/null
+++ b/esphome/components/modbus_server/__init__.py
@@ -0,0 +1,124 @@
+import esphome.codegen as cg
+from esphome.components import modbus
+from esphome.components.const import CONF_ENABLED
+from esphome.components.modbus.helpers import (
+    CPP_TYPE_REGISTER_MAP,
+    SENSOR_VALUE_TYPE,
+    TYPE_REGISTER_MAP,
+)
+import esphome.config_validation as cv
+from esphome.const import CONF_ADDRESS, CONF_ID
+
+from .const import (
+    CONF_COURTESY_RESPONSE,
+    CONF_READ_LAMBDA,
+    CONF_REGISTER_LAST_ADDRESS,
+    CONF_REGISTER_VALUE,
+    CONF_REGISTERS,
+    CONF_VALUE_TYPE,
+    CONF_WRITE_LAMBDA,
+)
+
+CODEOWNERS = ["@exciton"]
+
+AUTO_LOAD = ["modbus"]
+
+MULTI_CONF = True
+
+modbus_server_ns = cg.esphome_ns.namespace("modbus_server")
+ModbusServer = modbus_server_ns.class_(
+    "ModbusServer", cg.Component, modbus.ModbusDevice
+)
+
+ServerCourtesyResponse = modbus_server_ns.struct("ServerCourtesyResponse")
+ServerRegister = modbus_server_ns.struct("ServerRegister")
+
+SERVER_COURTESY_RESPONSE_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_ENABLED, default=False): cv.boolean,
+        cv.Optional(CONF_REGISTER_LAST_ADDRESS, default=0xFFFF): cv.hex_uint16_t,
+        cv.Optional(CONF_REGISTER_VALUE, default=0): cv.hex_uint16_t,
+    }
+)
+
+ModbusServerRegisterSchema = cv.Schema(
+    {
+        cv.GenerateID(): cv.declare_id(ServerRegister),
+        cv.Required(CONF_ADDRESS): cv.positive_int,
+        cv.Optional(CONF_VALUE_TYPE, default="U_WORD"): cv.enum(SENSOR_VALUE_TYPE),
+        cv.Required(CONF_READ_LAMBDA): cv.returning_lambda,
+        cv.Optional(CONF_WRITE_LAMBDA): cv.returning_lambda,
+    }
+)
+
+
+CONFIG_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(ModbusServer),
+            cv.Optional(CONF_COURTESY_RESPONSE): SERVER_COURTESY_RESPONSE_SCHEMA,
+            cv.Optional(
+                CONF_REGISTERS,
+            ): cv.ensure_list(ModbusServerRegisterSchema),
+        }
+    ).extend(modbus.modbus_device_schema(0x01)),
+)
+
+
+def _final_validate(config):
+    return modbus.final_validate_modbus_device("modbus_server", role="server")(config)
+
+
+FINAL_VALIDATE_SCHEMA = _final_validate
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    if server_courtesy_response := config.get(CONF_COURTESY_RESPONSE):
+        cg.add(
+            var.set_server_courtesy_response(
+                cg.StructInitializer(
+                    ServerCourtesyResponse,
+                    ("enabled", server_courtesy_response[CONF_ENABLED]),
+                    (
+                        "register_last_address",
+                        server_courtesy_response[CONF_REGISTER_LAST_ADDRESS],
+                    ),
+                    ("register_value", server_courtesy_response[CONF_REGISTER_VALUE]),
+                )
+            )
+        )
+    if CONF_REGISTERS in config:
+        for server_register in config[CONF_REGISTERS]:
+            server_register_var = cg.new_Pvariable(
+                server_register[CONF_ID],
+                server_register[CONF_ADDRESS],
+                server_register[CONF_VALUE_TYPE],
+                TYPE_REGISTER_MAP[server_register[CONF_VALUE_TYPE]],
+            )
+            cpp_type = CPP_TYPE_REGISTER_MAP[server_register[CONF_VALUE_TYPE]]
+            cg.add(
+                server_register_var.set_read_lambda(
+                    cg.TemplateArguments(cpp_type),
+                    await cg.process_lambda(
+                        server_register[CONF_READ_LAMBDA],
+                        [(cg.uint16, "address")],
+                        return_type=cpp_type,
+                    ),
+                )
+            )
+            if CONF_WRITE_LAMBDA in server_register:
+                cg.add(
+                    server_register_var.set_write_lambda(
+                        cg.TemplateArguments(cpp_type),
+                        await cg.process_lambda(
+                            server_register[CONF_WRITE_LAMBDA],
+                            parameters=[(cg.uint16, "address"), (cpp_type, "x")],
+                            return_type=cg.bool_,
+                        ),
+                    )
+                )
+            cg.add(var.add_server_register(server_register_var))
+    cg.add(var.set_address(config[CONF_ADDRESS]))
+    await cg.register_component(var, config)
+    return await modbus.register_modbus_device(var, config)
diff --git a/esphome/components/modbus_server/const.py b/esphome/components/modbus_server/const.py
new file mode 100644
index 0000000000..f83211c207
--- /dev/null
+++ b/esphome/components/modbus_server/const.py
@@ -0,0 +1,7 @@
+CONF_REGISTER_LAST_ADDRESS = "register_last_address"
+CONF_REGISTER_VALUE = "register_value"
+CONF_VALUE_TYPE = "value_type"
+CONF_COURTESY_RESPONSE = "courtesy_response"
+CONF_READ_LAMBDA = "read_lambda"
+CONF_WRITE_LAMBDA = "write_lambda"
+CONF_REGISTERS = "registers"
diff --git a/esphome/components/modbus_server/modbus_server.cpp b/esphome/components/modbus_server/modbus_server.cpp
new file mode 100644
index 0000000000..0063da3a1d
--- /dev/null
+++ b/esphome/components/modbus_server/modbus_server.cpp
@@ -0,0 +1,192 @@
+#include "modbus_server.h"
+#include "esphome/core/application.h"
+#include "esphome/core/log.h"
+
+namespace esphome::modbus_server {
+using modbus::ModbusFunctionCode;
+using modbus::ModbusExceptionCode;
+
+static const char *const TAG = "modbus_server";
+
+void ModbusServer::on_modbus_read_registers(uint8_t function_code, uint16_t start_address,
+                                            uint16_t number_of_registers) {
+  ESP_LOGD(TAG,
+           "Received read holding/input registers for device 0x%X. FC: 0x%X. Start address: 0x%X. Number of registers: "
+           "0x%X.",
+           this->address_, function_code, start_address, number_of_registers);
+
+  if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_READ) {
+    ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
+    return;
+  }
+
+  std::vector<uint16_t> sixteen_bit_response;
+  for (uint16_t current_address = start_address; current_address < start_address + number_of_registers;) {
+    bool found = false;
+    for (auto *server_register : this->server_registers_) {
+      if (server_register->address == current_address) {
+        if (!server_register->read_lambda) {
+          break;
+        }
+        int64_t value = server_register->read_lambda();
+        ESP_LOGD(TAG, "Matched register. Address: 0x%02X. Value type: %zu. Register count: %u. Value: %s.",
+                 server_register->address, static_cast<size_t>(server_register->value_type),
+                 server_register->register_count, server_register->format_value(value).c_str());
+
+        std::vector<uint16_t> payload;
+        payload.reserve(server_register->register_count * 2);
+        modbus::helpers::number_to_payload(payload, value, server_register->value_type);
+        sixteen_bit_response.insert(sixteen_bit_response.end(), payload.cbegin(), payload.cend());
+        current_address += server_register->register_count;
+        found = true;
+        break;
+      }
+    }
+
+    if (!found) {
+      if (this->server_courtesy_response_.enabled &&
+          (current_address <= this->server_courtesy_response_.register_last_address)) {
+        ESP_LOGD(TAG,
+                 "Could not match any register to address 0x%02X, but default allowed. "
+                 "Returning default value: %d.",
+                 current_address, this->server_courtesy_response_.register_value);
+        sixteen_bit_response.push_back(this->server_courtesy_response_.register_value);
+        current_address += 1;  // Just increment by 1, as the default response is a single register
+      } else {
+        ESP_LOGW(TAG,
+                 "Could not match any register to address 0x%02X and default not allowed. Sending exception response.",
+                 current_address);
+        this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_ADDRESS);
+        return;
+      }
+    }
+  }
+
+  std::vector<uint8_t> response;
+  for (auto v : sixteen_bit_response) {
+    auto decoded_value = decode_value(v);
+    response.push_back(decoded_value[0]);
+    response.push_back(decoded_value[1]);
+  }
+
+  this->send(function_code, start_address, number_of_registers, response.size(), response.data());
+}
+
+void ModbusServer::on_modbus_write_registers(uint8_t function_code, const std::vector<uint8_t> &data) {
+  uint16_t number_of_registers;
+  uint16_t payload_offset;
+
+  if (function_code == ModbusFunctionCode::WRITE_MULTIPLE_REGISTERS) {
+    if (data.size() < 5) {
+      ESP_LOGW(TAG, "Write multiple registers data too short (%zu bytes)", data.size());
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
+      return;
+    }
+    number_of_registers = uint16_t(data[3]) | (uint16_t(data[2]) << 8);
+    if (number_of_registers == 0 || number_of_registers > modbus::MAX_NUM_OF_REGISTERS_TO_WRITE) {
+      ESP_LOGW(TAG, "Invalid number of registers %d. Sending exception response.", number_of_registers);
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
+      return;
+    }
+    uint16_t payload_size = data[4];
+    if (payload_size != number_of_registers * 2) {
+      ESP_LOGW(TAG, "Payload size of %d bytes is not 2 times the number of registers (%d). Sending exception response.",
+               payload_size, number_of_registers);
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
+      return;
+    }
+    if (data.size() < 5 + payload_size) {
+      ESP_LOGW(TAG, "Write multiple registers payload truncated (%zu bytes, expected %u)", data.size(),
+               5 + payload_size);
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
+      return;
+    }
+    payload_offset = 5;
+  } else if (function_code == ModbusFunctionCode::WRITE_SINGLE_REGISTER) {
+    if (data.size() < 4) {
+      ESP_LOGW(TAG, "Write single register data too short (%zu bytes)", data.size());
+      this->send_error(function_code, ModbusExceptionCode::ILLEGAL_DATA_VALUE);
+      return;
+    }
+    number_of_registers = 1;
+    payload_offset = 2;
+  } else {
+    ESP_LOGW(TAG, "Invalid function code 0x%X. Sending exception response.", function_code);
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
+    return;
+  }
+
+  uint16_t start_address = uint16_t(data[1]) | (uint16_t(data[0]) << 8);
+  ESP_LOGD(TAG,
+           "Received write holding registers for device 0x%X. FC: 0x%X. Start address: 0x%X. Number of registers: "
+           "0x%X.",
+           this->address_, function_code, start_address, number_of_registers);
+
+  auto for_each_register = [this, start_address, number_of_registers, payload_offset](
+                               const std::function<bool(ServerRegister *, uint16_t offset)> &callback) -> bool {
+    uint16_t offset = payload_offset;
+    for (uint16_t current_address = start_address; current_address < start_address + number_of_registers;) {
+      bool ok = false;
+      for (auto *server_register : this->server_registers_) {
+        if (server_register->address == current_address) {
+          ok = callback(server_register, offset);
+          current_address += server_register->register_count;
+          offset += server_register->register_count * sizeof(uint16_t);
+          break;
+        }
+      }
+
+      if (!ok) {
+        return false;
+      }
+    }
+    return true;
+  };
+
+  // check all registers are writable before writing to any of them:
+  if (!for_each_register([](ServerRegister *server_register, uint16_t offset) -> bool {
+        return server_register->write_lambda != nullptr;
+      })) {
+    this->send_error(function_code, ModbusExceptionCode::ILLEGAL_FUNCTION);
+    return;
+  }
+
+  // Actually write to the registers:
+  if (!for_each_register([&data](ServerRegister *server_register, uint16_t offset) {
+        int64_t number = modbus::helpers::payload_to_number(data, server_register->value_type, offset, 0xFFFFFFFF);
+        return server_register->write_lambda(number);
+      })) {
+    this->send_error(function_code, ModbusExceptionCode::SERVICE_DEVICE_FAILURE);
+    return;
+  }
+
+  std::vector<uint8_t> response;
+  response.reserve(6);
+  response.push_back(this->address_);
+  response.push_back(function_code);
+  response.insert(response.end(), data.begin(), data.begin() + 4);
+  this->send_raw(response);
+}
+
+void ModbusServer::dump_config() {
+  ESP_LOGCONFIG(TAG,
+                "ModbusServer:\n"
+                "  Address: 0x%02X\n"
+                "  Server Courtesy Response:\n"
+                "    Enabled: %s\n"
+                "    Register Last Address: 0x%02X\n"
+                "    Register Value: %" PRIu16,
+                this->address_, this->server_courtesy_response_.enabled ? "true" : "false",
+                this->server_courtesy_response_.register_last_address, this->server_courtesy_response_.register_value);
+
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  ESP_LOGCONFIG(TAG, "server registers");
+  for (auto &r : this->server_registers_) {
+    ESP_LOGCONFIG(TAG, "  Address=0x%02X value_type=%u register_count=%u", r->address,
+                  static_cast<uint8_t>(r->value_type), r->register_count);
+  }
+#endif
+}
+
+}  // namespace esphome::modbus_server
diff --git a/esphome/components/modbus_server/modbus_server.h b/esphome/components/modbus_server/modbus_server.h
new file mode 100644
index 0000000000..0fc2e0bef5
--- /dev/null
+++ b/esphome/components/modbus_server/modbus_server.h
@@ -0,0 +1,119 @@
+#pragma once
+
+#include "esphome/core/component.h"
+
+#include "esphome/components/modbus/modbus.h"
+#include "esphome/components/modbus/modbus_helpers.h"
+#include "esphome/core/automation.h"
+
+#include <utility>
+#include <vector>
+
+namespace esphome::modbus_server {
+
+using modbus::helpers::SensorValueType;
+
+struct ServerCourtesyResponse {
+  bool enabled{false};
+  uint16_t register_last_address{0xFFFF};
+  uint16_t register_value{0};
+};
+
+class ServerRegister {
+  using ReadLambda = std::function<int64_t()>;
+  using WriteLambda = std::function<bool(int64_t value)>;
+
+ public:
+  ServerRegister(uint16_t address, SensorValueType value_type, uint8_t register_count) {
+    this->address = address;
+    this->value_type = value_type;
+    this->register_count = register_count;
+  }
+
+  template<typename T> void set_read_lambda(const std::function<T(uint16_t address)> &&user_read_lambda) {
+    this->read_lambda = [this, user_read_lambda]() -> int64_t {
+      T user_value = user_read_lambda(this->address);
+      if constexpr (std::is_same_v<T, float>) {
+        return bit_cast<uint32_t>(user_value);
+      } else {
+        return static_cast<int64_t>(user_value);
+      }
+    };
+  }
+
+  template<typename T>
+  void set_write_lambda(const std::function<bool(uint16_t address, const T v)> &&user_write_lambda) {
+    this->write_lambda = [this, user_write_lambda](int64_t number) {
+      if constexpr (std::is_same_v<T, float>) {
+        float float_value = bit_cast<float>(static_cast<uint32_t>(number));
+        return user_write_lambda(this->address, float_value);
+      }
+      return user_write_lambda(this->address, static_cast<T>(number));
+    };
+  }
+
+  // Formats a raw value into a string representation based on the value type for debugging
+  std::string format_value(int64_t value) const {
+    // max 44: float with %.1f can be up to 42 chars (3.4e38 → 39 integer digits + sign + decimal + 1 digit)
+    // plus null terminator = 43, rounded to 44 for 4-byte alignment
+    char buf[44];
+    switch (this->value_type) {
+      case SensorValueType::U_WORD:
+      case SensorValueType::U_DWORD:
+      case SensorValueType::U_DWORD_R:
+      case SensorValueType::U_QWORD:
+      case SensorValueType::U_QWORD_R:
+        buf_append_printf(buf, sizeof(buf), 0, "%" PRIu64, static_cast<uint64_t>(value));
+        return buf;
+      case SensorValueType::S_WORD:
+      case SensorValueType::S_DWORD:
+      case SensorValueType::S_DWORD_R:
+      case SensorValueType::S_QWORD:
+      case SensorValueType::S_QWORD_R:
+        buf_append_printf(buf, sizeof(buf), 0, "%" PRId64, value);
+        return buf;
+      case SensorValueType::FP32_R:
+      case SensorValueType::FP32:
+        buf_append_printf(buf, sizeof(buf), 0, "%.1f", bit_cast<float>(static_cast<uint32_t>(value)));
+        return buf;
+      default:
+        buf_append_printf(buf, sizeof(buf), 0, "%" PRId64, value);
+        return buf;
+    }
+  }
+
+  uint16_t address{0};
+  SensorValueType value_type{SensorValueType::RAW};
+  uint8_t register_count{0};
+  ReadLambda read_lambda;
+  WriteLambda write_lambda;
+};
+
+class ModbusServer : public Component, public modbus::ModbusDevice {
+ public:
+  void dump_config() override;
+
+  /// Not used for ModbusServer.
+  void on_modbus_data(const std::vector<uint8_t> &data) override{};
+  /// Registers a server register with the controller. Called by esphomes code generator
+  void add_server_register(ServerRegister *server_register) { server_registers_.push_back(server_register); }
+  /// called when a modbus request (function code 0x03 or 0x04) was parsed without errors
+  void on_modbus_read_registers(uint8_t function_code, uint16_t start_address, uint16_t number_of_registers) final;
+  /// called when a modbus request (function code 0x06 or 0x10) was parsed without errors
+  void on_modbus_write_registers(uint8_t function_code, const std::vector<uint8_t> &data) final;
+  /// Called by esphome generated code to set the server courtesy response object
+  void set_server_courtesy_response(const ServerCourtesyResponse &server_courtesy_response) {
+    this->server_courtesy_response_ = server_courtesy_response;
+  }
+  /// Get the server courtesy response object
+  ServerCourtesyResponse get_server_courtesy_response() const { return this->server_courtesy_response_; }
+
+ protected:
+  /// Collection of all server registers for this component
+  std::vector<ServerRegister *> server_registers_{};
+  /// Server courtesy response
+  ServerCourtesyResponse server_courtesy_response_{
+      .enabled = false, .register_last_address = 0xFFFF, .register_value = 0};
+};
+
+}  // namespace esphome::modbus_server
diff --git a/esphome/components/nextion/nextion_upload_arduino.cpp b/esphome/components/nextion/nextion_upload_arduino.cpp
index c79c68552e..41379c2345 100644
--- a/esphome/components/nextion/nextion_upload_arduino.cpp
+++ b/esphome/components/nextion/nextion_upload_arduino.cpp
@@ -16,6 +16,13 @@ namespace esphome::nextion {
 static const char *const TAG = "nextion.upload.arduino";
 static constexpr size_t NEXTION_MAX_RESPONSE_LOG_BYTES = 16;
 
+// Timeout for display acknowledgment during TFT upload (ms).
+// A single value is used for all chunks; the happy path returns as soon as
+// 0x05/0x08 arrives, so this only bounds failed-detection latency. Field
+// reports showed the previous 500ms steady-state value was too tight for
+// some firmware variants.
+static constexpr uint32_t NEXTION_UPLOAD_ACK_TIMEOUT_MS = 5000;
+
 // Followed guide
 // https://unofficialnextion.com/t/nextion-upload-protocol-v1-2-the-fast-one/1044/2
 
@@ -80,14 +87,41 @@ int Nextion::upload_by_chunks_(HTTPClient &http_client, uint32_t &range_start) {
       recv_string.clear();
       this->write_array(buffer, buffer_size);
       App.feed_wdt();
-      this->recv_ret_string_(recv_string, this->upload_first_chunk_sent_ ? 500 : 5000, true);
+      this->recv_ret_string_(recv_string, NEXTION_UPLOAD_ACK_TIMEOUT_MS, true);
+
+      // Some Nextion firmware variants (notably bootloader/recovery mode on panels
+      // with no installed TFT) emit the 5-byte 0x08+position fast-mode ack with a
+      // multi-second gap between the leading 0x08 byte and the 4 trailing position
+      // bytes. recv_ret_string_ returns after the first byte; manually drain the
+      // trailing bytes from the UART before continuing.
+      if (!recv_string.empty() && recv_string[0] == 0x08 && recv_string.size() < 5) {
+        const uint32_t deadline = millis() + NEXTION_UPLOAD_ACK_TIMEOUT_MS;
+        while (recv_string.size() < 5 && millis() < deadline) {
+          if (this->available()) {
+            uint8_t b = 0;
+            if (this->read_byte(&b)) {
+              recv_string.push_back(static_cast<char>(b));
+            }
+          } else {
+            delay(5);  // NOLINT
+            App.feed_wdt();
+          }
+        }
+        if (recv_string.size() < 5) {
+          ESP_LOGE(TAG, "Truncated 0x08 response: got %zu bytes within %" PRIu32 "ms", recv_string.size(),
+                   NEXTION_UPLOAD_ACK_TIMEOUT_MS);
+          allocator.deallocate(buffer, 4096);
+          buffer = nullptr;
+          return -1;
+        }
+      }
       this->content_length_ -= read_len;
       const float upload_percentage = 100.0f * (this->tft_size_ - this->content_length_) / this->tft_size_;
       ESP_LOGD(TAG, "Upload: %0.2f%% (%" PRIu32 " left, heap: %" PRIu32 ")", upload_percentage, this->content_length_,
                EspClass::getFreeHeap());
       this->upload_first_chunk_sent_ = true;
       if (recv_string.empty()) {
-        ESP_LOGW(TAG, "No response from display during upload");
+        ESP_LOGW(TAG, "No response from display after %" PRIu32 "ms", NEXTION_UPLOAD_ACK_TIMEOUT_MS);
         allocator.deallocate(buffer, 4096);
         buffer = nullptr;
         return -1;
@@ -324,7 +358,7 @@ bool Nextion::upload_tft(uint32_t baud_rate, bool exit_reparse) {
 
 #ifdef USE_ESP8266
 WiFiClient *Nextion::get_wifi_client_() {
-  if (this->tft_url_.compare(0, 6, "https:") == 0) {
+  if (this->tft_url_.starts_with("https:")) {
     if (this->wifi_client_secure_ == nullptr) {
       // NOLINTNEXTLINE(cppcoreguidelines-owning-memory)
       this->wifi_client_secure_ = new BearSSL::WiFiClientSecure();
diff --git a/esphome/components/nextion/nextion_upload_esp32.cpp b/esphome/components/nextion/nextion_upload_esp32.cpp
index 40a284dc46..cd8feab84f 100644
--- a/esphome/components/nextion/nextion_upload_esp32.cpp
+++ b/esphome/components/nextion/nextion_upload_esp32.cpp
@@ -19,6 +19,13 @@ namespace esphome::nextion {
 static const char *const TAG = "nextion.upload.esp32";
 static constexpr size_t NEXTION_MAX_RESPONSE_LOG_BYTES = 16;
 
+// Timeout for display acknowledgment during TFT upload (ms).
+// A single value is used for all chunks; the happy path returns as soon as
+// 0x05/0x08 arrives, so this only bounds failed-detection latency. Field
+// reports showed the previous 500ms steady-state value was too tight for
+// some firmware variants.
+static constexpr uint32_t NEXTION_UPLOAD_ACK_TIMEOUT_MS = 5000;
+
 // Followed guide
 // https://unofficialnextion.com/t/nextion-upload-protocol-v1-2-the-fast-one/1044/2
 
@@ -96,7 +103,34 @@ int Nextion::upload_by_chunks_(esp_http_client_handle_t http_client, uint32_t &r
       recv_string.clear();
       this->write_array(buffer, buffer_size);
       App.feed_wdt();
-      this->recv_ret_string_(recv_string, upload_first_chunk_sent_ ? 500 : 5000, true);
+      this->recv_ret_string_(recv_string, NEXTION_UPLOAD_ACK_TIMEOUT_MS, true);
+
+      // Some Nextion firmware variants (notably bootloader/recovery mode on panels
+      // with no installed TFT) emit the 5-byte 0x08+position fast-mode ack with a
+      // multi-second gap between the leading 0x08 byte and the 4 trailing position
+      // bytes. recv_ret_string_ returns after the first byte; manually drain the
+      // trailing bytes from the UART before continuing.
+      if (!recv_string.empty() && recv_string[0] == 0x08 && recv_string.size() < 5) {
+        const uint32_t deadline = millis() + NEXTION_UPLOAD_ACK_TIMEOUT_MS;
+        while (recv_string.size() < 5 && millis() < deadline) {
+          if (this->available()) {
+            uint8_t b = 0;
+            if (this->read_byte(&b)) {
+              recv_string.push_back(static_cast<char>(b));
+            }
+          } else {
+            vTaskDelay(pdMS_TO_TICKS(5));  // NOLINT
+            App.feed_wdt();
+          }
+        }
+        if (recv_string.size() < 5) {
+          ESP_LOGE(TAG, "Truncated 0x08 response: got %zu bytes within %" PRIu32 "ms", recv_string.size(),
+                   NEXTION_UPLOAD_ACK_TIMEOUT_MS);
+          allocator.deallocate(buffer, 4096);
+          buffer = nullptr;
+          return -1;
+        }
+      }
       this->content_length_ -= read_len;
       const float upload_percentage = 100.0f * (this->tft_size_ - this->content_length_) / this->tft_size_;
 #ifdef USE_PSRAM
@@ -109,7 +143,7 @@ int Nextion::upload_by_chunks_(esp_http_client_handle_t http_client, uint32_t &r
 #endif
       upload_first_chunk_sent_ = true;
       if (recv_string.empty()) {
-        ESP_LOGW(TAG, "No response from display during upload");
+        ESP_LOGW(TAG, "No response from display after %" PRIu32 "ms", NEXTION_UPLOAD_ACK_TIMEOUT_MS);
         allocator.deallocate(buffer, 4096);
         buffer = nullptr;
         return -1;
diff --git a/esphome/components/nrf52/__init__.py b/esphome/components/nrf52/__init__.py
index 5d92a4fa80..d2ed3b15e9 100644
--- a/esphome/components/nrf52/__init__.py
+++ b/esphome/components/nrf52/__init__.py
@@ -141,6 +141,22 @@ CONF_UICR_ERASE = "uicr_erase"
 VOLTAGE_LEVELS = [1.8, 2.1, 2.4, 2.7, 3.0, 3.3]
 
 
+_DFU_SCHEMA = cv.Schema(
+    {
+        cv.GenerateID(): cv.declare_id(DeviceFirmwareUpdate),
+        cv.Optional(CONF_RESET_PIN): pins.gpio_output_pin_schema,
+    }
+)
+
+
+def _dfu_schema(value: bool | ConfigType) -> ConfigType:
+    if isinstance(value, bool):
+        if not value:
+            raise cv.Invalid("Use 'dfu: true' or specify a configuration dict")
+        return _DFU_SCHEMA({})
+    return _DFU_SCHEMA(value)
+
+
 CONFIG_SCHEMA = cv.All(
     _detect_bootloader,
     set_core_data,
@@ -150,12 +166,7 @@ CONFIG_SCHEMA = cv.All(
                 cv.string_strict, cv.ByteLength(max=BOARD_MAX_LENGTH)
             ),
             cv.Optional(KEY_BOOTLOADER): cv.one_of(*BOOTLOADERS, lower=True),
-            cv.Optional(CONF_DFU): cv.Schema(
-                {
-                    cv.GenerateID(): cv.declare_id(DeviceFirmwareUpdate),
-                    cv.Required(CONF_RESET_PIN): pins.gpio_output_pin_schema,
-                }
-            ),
+            cv.Optional(CONF_DFU): _dfu_schema,
             cv.Optional(CONF_DCDC, default=True): cv.boolean,
             cv.Optional(CONF_REG0): cv.Schema(
                 {
@@ -321,8 +332,9 @@ async def to_code(config: ConfigType) -> None:
 async def _dfu_to_code(dfu_config):
     cg.add_define("USE_NRF52_DFU")
     var = cg.new_Pvariable(dfu_config[CONF_ID])
-    pin = await cg.gpio_pin_expression(dfu_config[CONF_RESET_PIN])
-    cg.add(var.set_reset_pin(pin))
+    if CONF_RESET_PIN in dfu_config:
+        pin = await cg.gpio_pin_expression(dfu_config[CONF_RESET_PIN])
+        cg.add(var.set_reset_pin(pin))
     zephyr_add_prj_conf("CDC_ACM_DTE_RATE_CALLBACK_SUPPORT", True)
     await cg.register_component(var, dfu_config)
 
diff --git a/esphome/components/nrf52/dfu.cpp b/esphome/components/nrf52/dfu.cpp
index c2017248d2..24dee99726 100644
--- a/esphome/components/nrf52/dfu.cpp
+++ b/esphome/components/nrf52/dfu.cpp
@@ -2,24 +2,34 @@
 
 #ifdef USE_NRF52_DFU
 
+#include "esphome/core/application.h"
 #include "esphome/core/log.h"
 #include "esphome/components/zephyr/cdc_acm.h"
 
-namespace esphome {
-namespace nrf52 {
+#include <hal/nrf_power.h>
+
+namespace esphome::nrf52 {
 
 static const char *const TAG = "dfu";
 
 static const uint32_t DFU_DBL_RESET_MAGIC = 0x5A1AD5;  // SALADS
+static const uint8_t DFU_MAGIC_UF2_RESET = 0x57;       // Adafruit nRF52 bootloader UF2 magic
 
 void DeviceFirmwareUpdate::setup() {
-  this->reset_pin_->setup();
+  if (this->reset_pin_ != nullptr) {
+    this->reset_pin_->setup();
+  }
 #if defined(CONFIG_CDC_ACM_DTE_RATE_CALLBACK_SUPPORT)
   zephyr::global_cdc_acm->add_on_rate_callback([this](const device *, uint32_t rate) {
     if (rate == 1200) {
       volatile uint32_t *dbl_reset_mem = (volatile uint32_t *) 0x20007F7C;
       (*dbl_reset_mem) = DFU_DBL_RESET_MAGIC;
-      this->reset_pin_->digital_write(true);
+      if (this->reset_pin_ != nullptr) {
+        this->reset_pin_->digital_write(true);
+      } else {
+        NRF_POWER->GPREGRET = DFU_MAGIC_UF2_RESET;
+        App.reboot();
+      }
     }
   });
 #endif
@@ -27,10 +37,13 @@ void DeviceFirmwareUpdate::setup() {
 
 void DeviceFirmwareUpdate::dump_config() {
   ESP_LOGCONFIG(TAG, "DFU:");
-  LOG_PIN("  RESET Pin: ", this->reset_pin_);
+  if (this->reset_pin_ != nullptr) {
+    LOG_PIN("  RESET Pin: ", this->reset_pin_);
+  } else {
+    ESP_LOGCONFIG(TAG, "  Method: GPREGRET");
+  }
 }
 
-}  // namespace nrf52
-}  // namespace esphome
+}  // namespace esphome::nrf52
 
 #endif
diff --git a/esphome/components/nrf52/dfu.h b/esphome/components/nrf52/dfu.h
index 71060e43c1..82c7d9f54e 100644
--- a/esphome/components/nrf52/dfu.h
+++ b/esphome/components/nrf52/dfu.h
@@ -5,8 +5,7 @@
 #include "esphome/core/component.h"
 #include "esphome/core/gpio.h"
 
-namespace esphome {
-namespace nrf52 {
+namespace esphome::nrf52 {
 class DeviceFirmwareUpdate : public Component {
  public:
   void setup() override;
@@ -14,10 +13,9 @@ class DeviceFirmwareUpdate : public Component {
   void dump_config() override;
 
  protected:
-  GPIOPin *reset_pin_;
+  GPIOPin *reset_pin_{nullptr};
 };
 
-}  // namespace nrf52
-}  // namespace esphome
+}  // namespace esphome::nrf52
 
 #endif
diff --git a/esphome/components/nrf52/uicr.cpp b/esphome/components/nrf52/uicr.cpp
index 4c0beeb503..03b07f8fe3 100644
--- a/esphome/components/nrf52/uicr.cpp
+++ b/esphome/components/nrf52/uicr.cpp
@@ -11,6 +11,7 @@ void nvmc_wait();
 nrfx_err_t nrfx_nvmc_uicr_erase();
 }
 
+// NOLINTBEGIN(clang-analyzer-core.FixedAddressDereference) -- NRF_UICR / NRF_TIMER2 are MMIO at fixed addresses
 namespace esphome::nrf52 {
 
 enum class StatusFlags : uint8_t {
@@ -113,6 +114,7 @@ static int board_esphome_init() {
   return 0;
 }
 }  // namespace esphome::nrf52
+// NOLINTEND(clang-analyzer-core.FixedAddressDereference)
 
 static int board_esphome_init() { return esphome::nrf52::board_esphome_init(); }
 
diff --git a/esphome/components/online_image/online_image.cpp b/esphome/components/online_image/online_image.cpp
index 24926aa4dc..a5a3ea5104 100644
--- a/esphome/components/online_image/online_image.cpp
+++ b/esphome/components/online_image/online_image.cpp
@@ -28,7 +28,7 @@ bool OnlineImage::validate_url_(const std::string &url) {
     ESP_LOGE(TAG, "URL is too long");
     return false;
   }
-  if (url.compare(0, 7, "http://") != 0 && url.compare(0, 8, "https://") != 0) {
+  if (!url.starts_with("http://") && !url.starts_with("https://")) {
     ESP_LOGE(TAG, "URL must start with http:// or https://");
     return false;
   }
diff --git a/esphome/components/ota/__init__.py b/esphome/components/ota/__init__.py
index 8f31eb5cdd..579491fe1a 100644
--- a/esphome/components/ota/__init__.py
+++ b/esphome/components/ota/__init__.py
@@ -24,6 +24,8 @@ def AUTO_LOAD() -> list[str]:
     components = ["safe_mode"]
     if not CORE.using_zephyr:
         components.extend(["md5"])
+    if CORE.is_esp32:
+        components.extend(["watchdog"])
     return components
 
 
diff --git a/esphome/components/ota/ota_backend.h b/esphome/components/ota/ota_backend.h
index bd9c481901..5888a8e12d 100644
--- a/esphome/components/ota/ota_backend.h
+++ b/esphome/components/ota/ota_backend.h
@@ -4,6 +4,8 @@
 #include "esphome/core/defines.h"
 #include "esphome/core/helpers.h"
 
+#include <cstdint>
+
 #ifdef USE_OTA_STATE_LISTENER
 #include <vector>
 #endif
@@ -23,6 +25,7 @@ enum OTAResponseTypes {
   OTA_RESPONSE_UPDATE_END_OK = 0x45,
   OTA_RESPONSE_SUPPORTS_COMPRESSION = 0x46,
   OTA_RESPONSE_CHUNK_OK = 0x47,
+  OTA_RESPONSE_FEATURE_FLAGS = 0x48,
 
   OTA_RESPONSE_ERROR_MAGIC = 0x80,
   OTA_RESPONSE_ERROR_UPDATE_PREPARE = 0x81,
@@ -38,6 +41,9 @@ enum OTAResponseTypes {
   OTA_RESPONSE_ERROR_MD5_MISMATCH = 0x8B,
   OTA_RESPONSE_ERROR_RP2040_NOT_ENOUGH_SPACE = 0x8C,
   OTA_RESPONSE_ERROR_SIGNATURE_INVALID = 0x8D,
+  OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE = 0x8E,
+  OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY = 0x8F,
+  OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE = 0x90,
   OTA_RESPONSE_ERROR_UNKNOWN = 0xFF,
 };
 
@@ -49,6 +55,11 @@ enum OTAState {
   OTA_ERROR,
 };
 
+enum OTAType : uint8_t {
+  OTA_TYPE_UPDATE_APP = 0x00,
+  OTA_TYPE_UPDATE_PARTITION_TABLE = 0x01,
+};
+
 /** Listener interface for OTA state changes.
  *
  * Components can implement this interface to receive OTA state updates
diff --git a/esphome/components/ota/ota_backend_arduino_libretiny.cpp b/esphome/components/ota/ota_backend_arduino_libretiny.cpp
index dcd71e92dd..4cc99202a7 100644
--- a/esphome/components/ota/ota_backend_arduino_libretiny.cpp
+++ b/esphome/components/ota/ota_backend_arduino_libretiny.cpp
@@ -13,7 +13,10 @@ static const char *const TAG = "ota.arduino_libretiny";
 
 std::unique_ptr<ArduinoLibreTinyOTABackend> make_ota_backend() { return make_unique<ArduinoLibreTinyOTABackend>(); }
 
-OTAResponseTypes ArduinoLibreTinyOTABackend::begin(size_t image_size) {
+OTAResponseTypes ArduinoLibreTinyOTABackend::begin(size_t image_size, OTAType ota_type) {
+  if (ota_type != OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
   // Handle UPDATE_SIZE_UNKNOWN (0) which is used by web server OTA
   // where the exact firmware size is unknown due to multipart encoding
   if (image_size == 0) {
diff --git a/esphome/components/ota/ota_backend_arduino_libretiny.h b/esphome/components/ota/ota_backend_arduino_libretiny.h
index 3d426e6759..c2716a44d1 100644
--- a/esphome/components/ota/ota_backend_arduino_libretiny.h
+++ b/esphome/components/ota/ota_backend_arduino_libretiny.h
@@ -8,7 +8,7 @@ namespace esphome::ota {
 
 class ArduinoLibreTinyOTABackend final {
  public:
-  OTAResponseTypes begin(size_t image_size);
+  OTAResponseTypes begin(size_t image_size, OTAType ota_type = OTA_TYPE_UPDATE_APP);
   void set_update_md5(const char *md5);
   OTAResponseTypes write(uint8_t *data, size_t len);
   OTAResponseTypes end();
diff --git a/esphome/components/ota/ota_backend_arduino_rp2040.cpp b/esphome/components/ota/ota_backend_arduino_rp2040.cpp
index bc8ef812e6..0ca0602519 100644
--- a/esphome/components/ota/ota_backend_arduino_rp2040.cpp
+++ b/esphome/components/ota/ota_backend_arduino_rp2040.cpp
@@ -15,7 +15,10 @@ static const char *const TAG = "ota.arduino_rp2040";
 
 std::unique_ptr<ArduinoRP2040OTABackend> make_ota_backend() { return make_unique<ArduinoRP2040OTABackend>(); }
 
-OTAResponseTypes ArduinoRP2040OTABackend::begin(size_t image_size) {
+OTAResponseTypes ArduinoRP2040OTABackend::begin(size_t image_size, OTAType ota_type) {
+  if (ota_type != OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
   // OTA size of 0 is not currently handled, but
   // web_server is not supported for RP2040, so this is not an issue.
   bool ret = Update.begin(image_size, U_FLASH);
diff --git a/esphome/components/ota/ota_backend_arduino_rp2040.h b/esphome/components/ota/ota_backend_arduino_rp2040.h
index 05bd2f5cc4..d04d5c1a84 100644
--- a/esphome/components/ota/ota_backend_arduino_rp2040.h
+++ b/esphome/components/ota/ota_backend_arduino_rp2040.h
@@ -10,7 +10,7 @@ namespace esphome::ota {
 
 class ArduinoRP2040OTABackend final {
  public:
-  OTAResponseTypes begin(size_t image_size);
+  OTAResponseTypes begin(size_t image_size, OTAType ota_type = OTA_TYPE_UPDATE_APP);
   void set_update_md5(const char *md5);
   OTAResponseTypes write(uint8_t *data, size_t len);
   OTAResponseTypes end();
diff --git a/esphome/components/ota/ota_backend_esp8266.cpp b/esphome/components/ota/ota_backend_esp8266.cpp
index 93e6249fb3..6a678fb419 100644
--- a/esphome/components/ota/ota_backend_esp8266.cpp
+++ b/esphome/components/ota/ota_backend_esp8266.cpp
@@ -50,7 +50,10 @@ static const char *const TAG = "ota.esp8266";
 
 std::unique_ptr<ESP8266OTABackend> make_ota_backend() { return make_unique<ESP8266OTABackend>(); }
 
-OTAResponseTypes ESP8266OTABackend::begin(size_t image_size) {
+OTAResponseTypes ESP8266OTABackend::begin(size_t image_size, OTAType ota_type) {
+  if (ota_type != OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
   // Handle UPDATE_SIZE_UNKNOWN (0) by calculating available space
   if (image_size == 0) {
     // Round down to sector boundary: subtract one sector, then mask to sector alignment
@@ -60,6 +63,7 @@ OTAResponseTypes ESP8266OTABackend::begin(size_t image_size) {
 
   // Check boot mode - if boot mode is UART download mode,
   // we will not be able to reset into normal mode once update is done
+  // NOLINTNEXTLINE(clang-analyzer-core.FixedAddressDereference) -- GPI is MMIO at a fixed address
   int boot_mode = (GPI >> BOOT_MODE_SHIFT) & BOOT_MODE_MASK;
   if (boot_mode == BOOT_MODE_UART_DOWNLOAD) {
     return OTA_RESPONSE_ERROR_INVALID_BOOTSTRAPPING;
diff --git a/esphome/components/ota/ota_backend_esp8266.h b/esphome/components/ota/ota_backend_esp8266.h
index b364e216a3..21b5c12c2d 100644
--- a/esphome/components/ota/ota_backend_esp8266.h
+++ b/esphome/components/ota/ota_backend_esp8266.h
@@ -14,7 +14,7 @@ namespace esphome::ota {
 /// by not having a global Update object in .bss.
 class ESP8266OTABackend final {
  public:
-  OTAResponseTypes begin(size_t image_size);
+  OTAResponseTypes begin(size_t image_size, OTAType ota_type = OTA_TYPE_UPDATE_APP);
   void set_update_md5(const char *md5);
   OTAResponseTypes write(uint8_t *data, size_t len);
   OTAResponseTypes end();
diff --git a/esphome/components/ota/ota_backend_esp_idf.cpp b/esphome/components/ota/ota_backend_esp_idf.cpp
index 598fce1562..42d106bf1f 100644
--- a/esphome/components/ota/ota_backend_esp_idf.cpp
+++ b/esphome/components/ota/ota_backend_esp_idf.cpp
@@ -2,6 +2,7 @@
 #include "ota_backend_esp_idf.h"
 
 #include "esphome/components/md5/md5.h"
+#include "esphome/components/watchdog/watchdog.h"
 #include "esphome/core/defines.h"
 #include "esphome/core/log.h"
 
@@ -15,7 +16,30 @@ static const char *const TAG = "ota.idf";
 
 std::unique_ptr<IDFOTABackend> make_ota_backend() { return make_unique<IDFOTABackend>(); }
 
-OTAResponseTypes IDFOTABackend::begin(size_t image_size) {
+OTAResponseTypes IDFOTABackend::begin(size_t image_size, ota::OTAType ota_type) {
+#ifdef USE_OTA_PARTITIONS
+  this->ota_type_ = ota_type;
+  if (this->ota_type_ == ota::OTA_TYPE_UPDATE_PARTITION_TABLE) {
+    // Reject any size other than ESP_PARTITION_TABLE_MAX_LEN: under- leaves stale bytes from the
+    // previous table; over- can't fit the reserved region.
+    if (image_size != ESP_PARTITION_TABLE_MAX_LEN) {
+      ESP_LOGE(TAG, "Wrong partition table size: expected %u bytes, got %zu", ESP_PARTITION_TABLE_MAX_LEN, image_size);
+      return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+    }
+    memset(this->buf_, 0xFF, sizeof this->buf_);
+    this->buf_written_ = 0;
+    this->image_size_ = image_size;
+    this->md5_.init();
+    return OTA_RESPONSE_OK;
+  }
+  if (this->ota_type_ != ota::OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
+#else
+  if (ota_type != ota::OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
+#endif
 #ifdef USE_OTA_ROLLBACK
   // If we're starting an OTA, the current boot is good enough - mark it valid
   // to prevent rollback and allow the OTA to proceed even if the safe mode
@@ -28,29 +52,9 @@ OTAResponseTypes IDFOTABackend::begin(size_t image_size) {
     return OTA_RESPONSE_ERROR_NO_UPDATE_PARTITION;
   }
 
-#if CONFIG_ESP_TASK_WDT_TIMEOUT_S < 15
-  // The following function takes longer than the 5 seconds timeout of WDT
-  esp_task_wdt_config_t wdtc;
-  wdtc.idle_core_mask = 0;
-#if CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0
-  wdtc.idle_core_mask |= (1 << 0);
-#endif
-#if CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1
-  wdtc.idle_core_mask |= (1 << 1);
-#endif
-  wdtc.timeout_ms = 15000;
-  wdtc.trigger_panic = false;
-  esp_task_wdt_reconfigure(&wdtc);
-#endif
-
+  watchdog::WatchdogManager watchdog(15000);
   esp_err_t err = esp_ota_begin(this->partition_, image_size, &this->update_handle_);
 
-#if CONFIG_ESP_TASK_WDT_TIMEOUT_S < 15
-  // Set the WDT back to the configured timeout
-  wdtc.timeout_ms = CONFIG_ESP_TASK_WDT_TIMEOUT_S * 1000;
-  esp_task_wdt_reconfigure(&wdtc);
-#endif
-
   if (err != ESP_OK) {
     esp_ota_abort(this->update_handle_);
     this->update_handle_ = 0;
@@ -71,6 +75,21 @@ void IDFOTABackend::set_update_md5(const char *expected_md5) {
 }
 
 OTAResponseTypes IDFOTABackend::write(uint8_t *data, size_t len) {
+#ifdef USE_OTA_PARTITIONS
+  if (this->ota_type_ == ota::OTA_TYPE_UPDATE_PARTITION_TABLE) {
+    if (len > PARTITION_TABLE_BUFFER_SIZE - this->buf_written_) {
+      ESP_LOGE(TAG, "Wrong partition table size");
+      return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+    }
+    memcpy(this->buf_ + this->buf_written_, data, len);
+    this->buf_written_ += len;
+    this->md5_.add(data, len);
+    return OTA_RESPONSE_OK;
+  }
+  if (this->ota_type_ != ota::OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
+#endif
   esp_err_t err = esp_ota_write(this->update_handle_, data, len);
   this->md5_.add(data, len);
   if (err != ESP_OK) {
@@ -92,6 +111,14 @@ OTAResponseTypes IDFOTABackend::end() {
       return OTA_RESPONSE_ERROR_MD5_MISMATCH;
     }
   }
+#ifdef USE_OTA_PARTITIONS
+  if (this->ota_type_ == ota::OTA_TYPE_UPDATE_PARTITION_TABLE) {
+    return this->update_partition_table();
+  }
+  if (this->ota_type_ != ota::OTA_TYPE_UPDATE_APP) {
+    return OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+  }
+#endif
   esp_err_t err = esp_ota_end(this->update_handle_);
   this->update_handle_ = 0;
   if (err == ESP_OK) {
@@ -115,6 +142,14 @@ OTAResponseTypes IDFOTABackend::end() {
 }
 
 void IDFOTABackend::abort() {
+#ifdef USE_OTA_PARTITIONS
+  if (this->partition_table_part_ != nullptr) {
+    esp_partition_deregister_external(this->partition_table_part_);
+    this->partition_table_part_ = nullptr;
+  }
+#endif
+  // esp_ota_abort with handle 0 returns ESP_ERR_INVALID_ARG harmlessly, so this is safe whether
+  // or not an update is in flight.
   esp_ota_abort(this->update_handle_);
   this->update_handle_ = 0;
 }
diff --git a/esphome/components/ota/ota_backend_esp_idf.h b/esphome/components/ota/ota_backend_esp_idf.h
index d007bcd128..54fdd24f93 100644
--- a/esphome/components/ota/ota_backend_esp_idf.h
+++ b/esphome/components/ota/ota_backend_esp_idf.h
@@ -9,21 +9,54 @@
 
 namespace esphome::ota {
 
+#ifdef USE_OTA_PARTITIONS
+// Staging buffer holds the entire partition table for verification before any flash op.
+static constexpr size_t PARTITION_TABLE_BUFFER_SIZE = ESP_PARTITION_TABLE_MAX_LEN;  // 0xC00
+
+void get_running_app_position(uint32_t &offset, size_t &size);
+#endif
+
 class IDFOTABackend final {
  public:
-  OTAResponseTypes begin(size_t image_size);
+  OTAResponseTypes begin(size_t image_size, ota::OTAType ota_type = ota::OTA_TYPE_UPDATE_APP);
   void set_update_md5(const char *md5);
   OTAResponseTypes write(uint8_t *data, size_t len);
   OTAResponseTypes end();
   void abort();
   bool supports_compression() { return false; }
 
+ protected:
+#ifdef USE_OTA_PARTITIONS
+  // copy_dest_part non-null means the running app must be copied INTO this slot of the current
+  // table before the new partition table is committed. The destination is in the current table
+  // because that's where esp_partition_copy can write; once the new table replaces it, the same
+  // flash region becomes target_app_index in the new table.
+  struct PartitionTablePlan {
+    int target_app_index{-1};
+    const esp_partition_t *copy_dest_part{nullptr};
+  };
+
+  OTAResponseTypes validate_new_partition_table_(uint32_t running_app_offset, size_t running_app_size,
+                                                 PartitionTablePlan &plan);
+  OTAResponseTypes update_partition_table();
+#endif
+
  private:
   esp_ota_handle_t update_handle_{0};
   const esp_partition_t *partition_;
   md5::MD5Digest md5_{};
   char expected_bin_md5_[32];
   bool md5_set_{false};
+#ifdef USE_OTA_PARTITIONS
+  // Buffer first so it packs tightly after the preceding `bool md5_set_` with no alignment
+  // padding. Only resident during an active OTA: the backend is constructed per connection and
+  // destroyed on cleanup_connection_().
+  uint8_t buf_[PARTITION_TABLE_BUFFER_SIZE];
+  size_t buf_written_{0};
+  size_t image_size_{0};
+  const esp_partition_t *partition_table_part_{nullptr};
+  ota::OTAType ota_type_{ota::OTA_TYPE_UPDATE_APP};
+#endif
 };
 
 std::unique_ptr<IDFOTABackend> make_ota_backend();
diff --git a/esphome/components/ota/ota_backend_host.cpp b/esphome/components/ota/ota_backend_host.cpp
index 2e2132418d..a2c9f2cc33 100644
--- a/esphome/components/ota/ota_backend_host.cpp
+++ b/esphome/components/ota/ota_backend_host.cpp
@@ -10,7 +10,9 @@ namespace esphome::ota {
 
 std::unique_ptr<HostOTABackend> make_ota_backend() { return make_unique<HostOTABackend>(); }
 
-OTAResponseTypes HostOTABackend::begin(size_t image_size) { return OTA_RESPONSE_ERROR_UPDATE_PREPARE; }
+OTAResponseTypes HostOTABackend::begin(size_t image_size, OTAType ota_type) {
+  return OTA_RESPONSE_ERROR_UPDATE_PREPARE;
+}
 
 void HostOTABackend::set_update_md5(const char *expected_md5) {}
 
diff --git a/esphome/components/ota/ota_backend_host.h b/esphome/components/ota/ota_backend_host.h
index 300facf72f..4451fdfe18 100644
--- a/esphome/components/ota/ota_backend_host.h
+++ b/esphome/components/ota/ota_backend_host.h
@@ -9,7 +9,7 @@ namespace esphome::ota {
 /// OTA triggers to compile for host platform during development.
 class HostOTABackend final {
  public:
-  OTAResponseTypes begin(size_t image_size);
+  OTAResponseTypes begin(size_t image_size, OTAType ota_type = OTA_TYPE_UPDATE_APP);
   void set_update_md5(const char *md5);
   OTAResponseTypes write(uint8_t *data, size_t len);
   OTAResponseTypes end();
diff --git a/esphome/components/ota/ota_partitions_esp_idf.cpp b/esphome/components/ota/ota_partitions_esp_idf.cpp
new file mode 100644
index 0000000000..2a2ed577f1
--- /dev/null
+++ b/esphome/components/ota/ota_partitions_esp_idf.cpp
@@ -0,0 +1,327 @@
+#ifdef USE_ESP32
+#include "ota_backend_esp_idf.h"
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_OTA_PARTITIONS
+#include "esphome/components/watchdog/watchdog.h"
+#include "esphome/core/log.h"
+
+#include <esp_image_format.h>
+#include <esp_ota_ops.h>
+#include <nvs_flash.h>
+
+#include <cstring>
+
+namespace esphome::ota {
+
+static const char *const TAG = "ota.idf";
+
+static inline bool check_overlap(uint32_t a_offset, size_t a_size, uint32_t b_offset, size_t b_size) {
+  return (a_offset + a_size > b_offset && b_offset + b_size > a_offset);
+}
+
+// Wraps esp_partition_find/_get/_next/_release. Returns nullptr if no APP partition at `address`
+// is at least `min_size` bytes.
+static const esp_partition_t *find_app_partition_at(uint32_t address, size_t min_size) {
+  const esp_partition_t *found = nullptr;
+  esp_partition_iterator_t it = esp_partition_find(ESP_PARTITION_TYPE_APP, ESP_PARTITION_SUBTYPE_ANY, nullptr);
+  while (it != nullptr) {
+    const esp_partition_t *p = esp_partition_get(it);
+    if (p->address == address && p->size >= min_size) {
+      found = p;
+      break;
+    }
+    it = esp_partition_next(it);
+  }
+  esp_partition_iterator_release(it);
+  return found;
+}
+
+// Validates the staged partition table and picks the post-update boot slot. All non-destructive
+// checks live here; the destructive write is in update_partition_table().
+// Side effect: registers the live partition-table region as partition_table_part_ so the caller
+// can write to it; abort() releases it on error.
+OTAResponseTypes IDFOTABackend::validate_new_partition_table_(uint32_t running_app_offset, size_t running_app_size,
+                                                              PartitionTablePlan &plan) {
+  esp_err_t err = esp_partition_register_external(
+      nullptr, ESP_PRIMARY_PARTITION_TABLE_OFFSET, ESP_PARTITION_TABLE_SIZE, "PrimaryPrtTable",
+      ESP_PARTITION_TYPE_PARTITION_TABLE, ESP_PARTITION_SUBTYPE_PARTITION_TABLE_PRIMARY, &this->partition_table_part_);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_partition_register_external failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  int num_partitions = 0;
+  const esp_partition_info_t *existing_partition_table = nullptr;
+  esp_partition_mmap_handle_t partition_table_map;
+  err = esp_partition_mmap(this->partition_table_part_, 0, ESP_PARTITION_TABLE_MAX_LEN, ESP_PARTITION_MMAP_DATA,
+                           reinterpret_cast<const void **>(&existing_partition_table), &partition_table_map);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_partition_mmap failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+  err = esp_partition_table_verify(existing_partition_table, true, &num_partitions);
+  esp_partition_munmap(partition_table_map);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_partition_table_verify failed (existing partition table) (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  const esp_partition_info_t *new_partition_table = reinterpret_cast<const esp_partition_info_t *>(this->buf_);
+  err = esp_partition_table_verify(new_partition_table, true, &num_partitions);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_partition_table_verify failed (new partition table) (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  // esp_partition_table_verify does not catch a missing MD5 entry, but the bootloader refuses
+  // to boot from a table without one.
+  bool checksum_found = false;
+  for (size_t i = 0; i < ESP_PARTITION_TABLE_MAX_ENTRIES; i++) {
+    if (new_partition_table[i].magic == ESP_PARTITION_MAGIC_MD5) {
+      checksum_found = true;
+      break;
+    }
+  }
+  if (!checksum_found) {
+    ESP_LOGE(TAG, "New partition table has no checksum");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  // Slot-selection policy when multiple slots can host the running app: pick the FIRST eligible
+  // slot in table order, preferring the no-copy path (matching offset) over the copy path.
+  // Deterministic and table-ordering-stable.
+  int app_partitions_found = 0;
+  int new_app_part_index = -1;
+  int new_app_part_index_with_copy = -1;
+  const esp_partition_t *app_copy_dest_part = nullptr;
+  bool otadata_partition_found = false;
+  bool otadata_overlap = false;
+  bool nvs_partition_found = false;
+  for (int i = 0; i < num_partitions; i++) {
+    const esp_partition_info_t *new_part = &new_partition_table[i];
+    if (new_part->type == ESP_PARTITION_TYPE_APP) {
+      app_partitions_found++;
+      if (new_part->pos.size >= running_app_size) {
+        if (new_part->pos.offset == running_app_offset) {
+          if (new_app_part_index == -1) {
+            new_app_part_index = i;
+          }
+        } else if (new_app_part_index_with_copy == -1 &&
+                   !check_overlap(running_app_offset, running_app_size, new_part->pos.offset, running_app_size)) {
+          // esp_partition_copy writes into a registered partition; need one at this offset in the
+          // current table.
+          const esp_partition_t *p = find_app_partition_at(new_part->pos.offset, running_app_size);
+          if (p != nullptr) {
+            new_app_part_index_with_copy = i;
+            app_copy_dest_part = p;
+          }
+        }
+      }
+    } else if (new_part->type == ESP_PARTITION_TYPE_DATA) {
+      if (new_part->subtype == ESP_PARTITION_SUBTYPE_DATA_OTA) {
+        otadata_partition_found = true;
+        otadata_overlap = check_overlap(running_app_offset, running_app_size, new_part->pos.offset, new_part->pos.size);
+      } else if (new_part->subtype == ESP_PARTITION_SUBTYPE_DATA_NVS &&
+                 strncmp(reinterpret_cast<const char *>(new_part->label), "nvs", sizeof(new_part->label)) == 0) {
+        nvs_partition_found = true;
+      }
+    }
+  }
+
+  if (new_app_part_index == -1 && new_app_part_index_with_copy == -1) {
+    // Most likely cause: the user picked the wrong migration .bin for their running app's size.
+    // Rejecting here is non-destructive (no flash op has run yet); the user can safely retry with
+    // a different .bin. Log enough info that they can pick the right method without guessing.
+    ESP_LOGE(TAG,
+             "Running app at 0x%X (%u bytes used) does not fit any compatible slot in the new "
+             "partition table. Pick a migration method whose size limit is at least %u bytes and "
+             "retry; no flash content was modified.",
+             running_app_offset, running_app_size, running_app_size);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+  if (app_partitions_found < 2) {
+    ESP_LOGE(TAG, "New partition table needs at least 2 app partitions, found %d", app_partitions_found);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+  if (!otadata_partition_found) {
+    ESP_LOGE(TAG, "New partition table is missing the required otadata partition");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+  if (!nvs_partition_found) {
+    ESP_LOGE(TAG, "New partition table is missing the required nvs partition");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+  if (otadata_overlap) {
+    ESP_LOGE(TAG,
+             "New otadata partition overlaps with the running app at 0x%X (size %u). The chosen "
+             "partition table is not compatible with this device's current flash layout; pick a "
+             "different migration method.",
+             running_app_offset, running_app_size);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  if (new_app_part_index != -1) {
+    plan.target_app_index = new_app_part_index;
+    plan.copy_dest_part = nullptr;
+  } else {
+    plan.target_app_index = new_app_part_index_with_copy;
+    plan.copy_dest_part = app_copy_dest_part;
+  }
+  return OTA_RESPONSE_OK;
+}
+
+OTAResponseTypes IDFOTABackend::update_partition_table() {
+  if (this->buf_written_ == 0 || this->image_size_ != this->buf_written_) {
+    ESP_LOGE(TAG, "Not enough data received");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  // Without a valid running-app size we cannot compute overlap or copy bounds. zero indicates
+  // esp_ota_get_running_partition() failed (e.g. cache unloaded by a previous aborted OTA).
+  uint32_t running_app_offset;
+  size_t running_app_size;
+  get_running_app_position(running_app_offset, running_app_size);
+  if (running_app_size == 0) {
+    ESP_LOGE(TAG, "Failed to determine running app position");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_VERIFY;
+  }
+
+  PartitionTablePlan plan;
+  OTAResponseTypes validate_result = this->validate_new_partition_table_(running_app_offset, running_app_size, plan);
+  if (validate_result != OTA_RESPONSE_OK) {
+    return validate_result;
+  }
+
+  // ERROR severity so the warning shows up in default log filters; any failure past this point
+  // can leave the device unbootable until it is recovered with a serial flash.
+  ESP_LOGE(TAG, "Starting partition table update.\n"
+                "  DO NOT REMOVE POWER until the device reboots successfully.\n"
+                "  Loss of power during this operation may render the device unable to boot until\n"
+                "  it is recovered via a serial flash.");
+
+  // One guard over the whole critical section in case an IDF call takes longer than expected on
+  // some chip variant.
+  watchdog::WatchdogManager watchdog(15000);
+
+  esp_err_t err;
+  const esp_partition_info_t *new_partition_table = reinterpret_cast<const esp_partition_info_t *>(this->buf_);
+
+  if (plan.copy_dest_part != nullptr) {
+    // Resolve the source via running_app_offset rather than esp_ota_get_running_partition() in
+    // case a prior aborted partition-table OTA called esp_partition_unload_all() in this boot,
+    // which leaves esp_ota_get_running_partition() returning nullptr.
+    const esp_partition_t *running_app_part = find_app_partition_at(running_app_offset, running_app_size);
+    if (running_app_part == nullptr) {
+      ESP_LOGE(TAG, "Cannot resolve running app partition at offset 0x%X", running_app_offset);
+      return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+    }
+    ESP_LOGD(TAG, "Copying running app from 0x%X to 0x%X (size: 0x%X)", running_app_part->address,
+             plan.copy_dest_part->address, running_app_size);
+    err = esp_partition_copy(plan.copy_dest_part, 0, running_app_part, 0, running_app_size);
+    if (err != ESP_OK) {
+      ESP_LOGE(TAG, "esp_partition_copy failed (err=0x%X)", err);
+      return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+    }
+  }
+
+  // Deinit NVS only just before the first destructive write so verify/copy failure paths return
+  // with NVS still functional. From this point on, components that hold open NVS handles
+  // (e.g. preferences) will fail with ESP_ERR_NVS_INVALID_HANDLE on success or failure;
+  // nvs_flash_init() can re-init the subsystem but cannot revive existing handles. On the
+  // success path the device reboots immediately afterwards so this doesn't matter; on the
+  // failure path the user must reboot the device before retrying.
+  nvs_flash_deinit();
+
+  // Update the partition table
+  err = esp_ota_begin(this->partition_table_part_, ESP_PARTITION_TABLE_MAX_LEN, &this->update_handle_);
+  if (err != ESP_OK) {
+    esp_ota_abort(this->update_handle_);
+    this->update_handle_ = 0;
+    ESP_LOGE(TAG, "esp_ota_begin failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+  }
+  err = esp_ota_write(this->update_handle_, this->buf_, ESP_PARTITION_TABLE_MAX_LEN);
+  if (err != ESP_OK) {
+    esp_ota_abort(this->update_handle_);
+    this->update_handle_ = 0;
+    ESP_LOGE(TAG, "esp_ota_write failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+  }
+  err = esp_ota_end(this->update_handle_);
+  this->update_handle_ = 0;  // esp_ota_end releases the handle internally
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_ota_end failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+  }
+  // unload first, then null the member pointer; if abort() ran between the two steps it would
+  // see a freed pointer. esp_partition_unload_all() invalidates partition_table_part_ too, so
+  // an explicit deregister would be redundant.
+  esp_partition_unload_all();
+  this->partition_table_part_ = nullptr;
+
+  // Write otadata to set the new boot partition
+  const esp_partition_info_t *new_part = &new_partition_table[plan.target_app_index];
+  const esp_partition_t *new_boot_partition = find_app_partition_at(new_part->pos.offset, 0);
+  if (new_boot_partition == nullptr) {
+    ESP_LOGE(TAG, "Selected app partition not found after partition table update");
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+  }
+  ESP_LOGD(TAG, "Setting next boot partition to 0x%X", new_boot_partition->address);
+  err = esp_ota_set_boot_partition(new_boot_partition);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "esp_ota_set_boot_partition failed (err=0x%X)", err);
+    return OTA_RESPONSE_ERROR_PARTITION_TABLE_UPDATE;
+  }
+  return OTA_RESPONSE_OK;
+}
+
+// Process-scoped cache. Cannot be a backend member: backends are per-connection but the cache
+// must outlive a connection that called esp_partition_unload_all(), after which
+// esp_ota_get_running_partition() no longer returns valid data.
+static bool s_running_app_initialized = false;
+static uint32_t s_running_app_cached_offset = 0;
+static size_t s_running_app_cached_size = 0;
+
+// Flag-gated rather than size==0 so a failed first call doesn't poison the cache.
+void get_running_app_position(uint32_t &offset, size_t &size) {
+  if (!s_running_app_initialized) {
+    const esp_partition_t *running_app_part = esp_ota_get_running_partition();
+    if (running_app_part == nullptr || running_app_part->erase_size == 0) {
+      // Surface zeros without committing to the cache so a later call has a chance to succeed.
+      offset = 0;
+      size = 0;
+      return;
+    }
+
+    uint32_t pending_offset = running_app_part->address;
+    size_t pending_size = running_app_part->size;
+
+    const esp_partition_pos_t running_app_pos = {
+        .offset = running_app_part->address,
+        .size = running_app_part->size,
+    };
+    esp_image_metadata_t image_metadata = {};
+    image_metadata.start_addr = running_app_part->address;
+    if (esp_image_verify(ESP_IMAGE_VERIFY_SILENT, &running_app_pos, &image_metadata) == ESP_OK &&
+        image_metadata.image_len < running_app_part->size) {
+      pending_size = image_metadata.image_len;
+    }
+    // Round up to a full flash sector so the copy spans complete erase blocks.
+    pending_size = ((pending_size + running_app_part->erase_size - 1) / running_app_part->erase_size) *
+                   running_app_part->erase_size;
+
+    s_running_app_cached_offset = pending_offset;
+    s_running_app_cached_size = pending_size;
+    s_running_app_initialized = true;
+  }
+
+  offset = s_running_app_cached_offset;
+  size = s_running_app_cached_size;
+}
+
+}  // namespace esphome::ota
+
+#endif  // USE_OTA_PARTITIONS
+#endif  // USE_ESP32
diff --git a/esphome/components/output/__init__.py b/esphome/components/output/__init__.py
index 36798f2d7f..4f6c8943f5 100644
--- a/esphome/components/output/__init__.py
+++ b/esphome/components/output/__init__.py
@@ -54,10 +54,16 @@ async def setup_output_platform_(obj, config):
         power_supply_ = await cg.get_variable(config[CONF_POWER_SUPPLY])
         cg.add(obj.set_power_supply(power_supply_))
     if CONF_MAX_POWER in config:
+        cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
         cg.add(obj.set_max_power(config[CONF_MAX_POWER]))
     if CONF_MIN_POWER in config:
+        cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
         cg.add(obj.set_min_power(config[CONF_MIN_POWER]))
-    if CONF_ZERO_MEANS_ZERO in config:
+    # Only emit when zero_means_zero is actually enabled. The schema defaults to False
+    # so this key is always present; emitting unconditionally would force
+    # USE_OUTPUT_FLOAT_POWER_SCALING on for every output, defeating the gate.
+    if config.get(CONF_ZERO_MEANS_ZERO):
+        cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
         cg.add(obj.set_zero_means_zero(config[CONF_ZERO_MEANS_ZERO]))
 
 
@@ -121,6 +127,7 @@ async def output_set_level_to_code(config, action_id, template_arg, args):
     synchronous=True,
 )
 async def output_set_min_power_to_code(config, action_id, template_arg, args):
+    cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
     paren = await cg.get_variable(config[CONF_ID])
     var = cg.new_Pvariable(action_id, template_arg, paren)
     template_ = await cg.templatable(config[CONF_MIN_POWER], args, cg.float_)
@@ -140,6 +147,7 @@ async def output_set_min_power_to_code(config, action_id, template_arg, args):
     synchronous=True,
 )
 async def output_set_max_power_to_code(config, action_id, template_arg, args):
+    cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
     paren = await cg.get_variable(config[CONF_ID])
     var = cg.new_Pvariable(action_id, template_arg, paren)
     template_ = await cg.templatable(config[CONF_MAX_POWER], args, cg.float_)
diff --git a/esphome/components/output/automation.h b/esphome/components/output/automation.h
index 3279378129..537226a143 100644
--- a/esphome/components/output/automation.h
+++ b/esphome/components/output/automation.h
@@ -2,6 +2,7 @@
 
 #include "esphome/core/component.h"
 #include "esphome/core/automation.h"
+#include "esphome/core/defines.h"
 #include "esphome/components/output/binary_output.h"
 #include "esphome/components/output/float_output.h"
 
@@ -40,6 +41,7 @@ template<typename... Ts> class SetLevelAction : public Action<Ts...> {
   FloatOutput *output_;
 };
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
 template<typename... Ts> class SetMinPowerAction : public Action<Ts...> {
  public:
   SetMinPowerAction(FloatOutput *output) : output_(output) {}
@@ -63,6 +65,7 @@ template<typename... Ts> class SetMaxPowerAction : public Action<Ts...> {
  protected:
   FloatOutput *output_;
 };
+#endif  // USE_OUTPUT_FLOAT_POWER_SCALING
 
 }  // namespace output
 }  // namespace esphome
diff --git a/esphome/components/output/float_output.cpp b/esphome/components/output/float_output.cpp
index 46014e0903..35629c828a 100644
--- a/esphome/components/output/float_output.cpp
+++ b/esphome/components/output/float_output.cpp
@@ -7,13 +7,15 @@ namespace output {
 
 static const char *const TAG = "output.float";
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
 void FloatOutput::set_max_power(float max_power) {
-  this->max_power_ = clamp(max_power, this->min_power_, 1.0f);  // Clamp to MIN>=MAX>=1.0
+  this->max_power_ = clamp(max_power, this->min_power_, 1.0f);  // Clamp to min_power <= max <= 1.0
 }
 
 void FloatOutput::set_min_power(float min_power) {
-  this->min_power_ = clamp(min_power, 0.0f, this->max_power_);  // Clamp to 0.0>=MIN>=MAX
+  this->min_power_ = clamp(min_power, 0.0f, this->max_power_);  // Clamp to 0.0 <= min <= max_power
 }
+#endif
 
 void FloatOutput::set_level(float state) {
   state = clamp(state, 0.0f, 1.0f);
@@ -26,8 +28,10 @@ void FloatOutput::set_level(float state) {
   }
 #endif
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
   if (state != 0.0f || !this->zero_means_zero_)  // regardless of min_power_, 0.0 means off
     state = (state * (this->max_power_ - this->min_power_)) + this->min_power_;
+#endif
 
   if (this->is_inverted())
     state = 1.0f - state;
diff --git a/esphome/components/output/float_output.h b/esphome/components/output/float_output.h
index 5225f88c66..3e1bd83968 100644
--- a/esphome/components/output/float_output.h
+++ b/esphome/components/output/float_output.h
@@ -1,11 +1,13 @@
 #pragma once
 
 #include "esphome/core/component.h"
+#include "esphome/core/defines.h"
 #include "binary_output.h"
 
 namespace esphome {
 namespace output {
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
 #define LOG_FLOAT_OUTPUT(this) \
   LOG_BINARY_OUTPUT(this) \
   if (this->max_power_ != 1.0f) { \
@@ -14,6 +16,9 @@ namespace output {
   if (this->min_power_ != 0.0f) { \
     ESP_LOGCONFIG(TAG, "  Min Power: %.1f%%", this->min_power_ * 100.0f); \
   }
+#else
+#define LOG_FLOAT_OUTPUT(this) LOG_BINARY_OUTPUT(this)
+#endif
 
 /** Base class for all output components that can output a variable level, like PWM.
  *
@@ -22,14 +27,18 @@ namespace output {
  * makes using maths much easier and (in theory) supports all possible bit depths.
  *
  * If you want to create a FloatOutput yourself, you essentially just have to override write_state(float).
- * That method will be called for you with inversion and max-min power and offset to min power already applied.
+ * That method will be called for you with inversion already applied. When USE_OUTPUT_FLOAT_POWER_SCALING is
+ * enabled (set automatically by Python codegen if any output uses min_power/max_power/zero_means_zero or the
+ * matching runtime actions), the value will additionally have max-min power scaling and offset to min_power
+ * applied; otherwise only inversion is applied.
  *
  * This interface is compatible with BinaryOutput (and will automatically convert the binary states to floating
  * point states for you). Additionally, this class provides a way for users to set a minimum and/or maximum power
- * output
+ * output (gated on USE_OUTPUT_FLOAT_POWER_SCALING).
  */
 class FloatOutput : public BinaryOutput {
  public:
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
   /** Set the maximum power output of this component.
    *
    * All values are multiplied by max_power - min_power and offset to min_power to get the adjusted value.
@@ -51,6 +60,32 @@ class FloatOutput : public BinaryOutput {
    * @param zero_means_zero True if a 0 state should mean 0 and not min_power.
    */
   void set_zero_means_zero(bool zero_means_zero) { this->zero_means_zero_ = zero_means_zero; }
+#else
+  // Compile-time guards for users calling these methods from lambdas (documented usage at
+  // https://esphome.io/components/output/#output-set_min_power_action). When power scaling
+  // is compiled out, these template stubs fail to compile with an actionable error pointing
+  // at the user's lambda. Templating on a default-false bool means static_assert only fires
+  // on instantiation (i.e. when the user actually calls the method), not on every parse.
+  template<bool _use_output_float_power_scaling = false> void set_max_power(float max_power) {
+    static_assert(_use_output_float_power_scaling,
+                  "set_max_power() requires USE_OUTPUT_FLOAT_POWER_SCALING. "
+                  "To enable it, add 'max_power: 100%' (or any value) to one output entry in your YAML — "
+                  "the codegen will then keep the scaling fields. "
+                  "See https://esphome.io/components/output/ for details.");
+  }
+  template<bool _use_output_float_power_scaling = false> void set_min_power(float min_power) {
+    static_assert(_use_output_float_power_scaling,
+                  "set_min_power() requires USE_OUTPUT_FLOAT_POWER_SCALING. "
+                  "To enable it, add 'min_power: 0%' (or any value) to one output entry in your YAML — "
+                  "the codegen will then keep the scaling fields. "
+                  "See https://esphome.io/components/output/ for details.");
+  }
+  template<bool _use_output_float_power_scaling = false> void set_zero_means_zero(bool zero_means_zero) {
+    static_assert(_use_output_float_power_scaling,
+                  "set_zero_means_zero() requires USE_OUTPUT_FLOAT_POWER_SCALING. "
+                  "To enable it, add 'zero_means_zero: true' to one output entry in your YAML.");
+  }
+#endif
 
   /** Set the level of this float output, this is called from the front-end.
    *
@@ -69,20 +104,30 @@ class FloatOutput : public BinaryOutput {
   // ========== INTERNAL METHODS ==========
   // (In most use cases you won't need these)
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
   /// Get the maximum power output.
   float get_max_power() const { return this->max_power_; }
 
   /// Get the minimum power output.
   float get_min_power() const { return this->min_power_; }
+#else
+  /// Get the maximum power output.
+  float get_max_power() const { return 1.0f; }
+
+  /// Get the minimum power output.
+  float get_min_power() const { return 0.0f; }
+#endif
 
  protected:
   /// Implement BinarySensor's write_enabled; this should never be called.
   void write_state(bool state) override;
   virtual void write_state(float state) = 0;
 
+#ifdef USE_OUTPUT_FLOAT_POWER_SCALING
   float max_power_{1.0f};
   float min_power_{0.0f};
-  bool zero_means_zero_;
+  bool zero_means_zero_{false};
+#endif
 };
 
 }  // namespace output
diff --git a/esphome/components/pipsolar/pipsolar.cpp b/esphome/components/pipsolar/pipsolar.cpp
index c304d206c0..5123d8d9d3 100644
--- a/esphome/components/pipsolar/pipsolar.cpp
+++ b/esphome/components/pipsolar/pipsolar.cpp
@@ -433,13 +433,17 @@ void Pipsolar::handle_qpigs_(const char *message) {
 }
 
 void Pipsolar::handle_qmod_(const char *message) {
-  std::string mode;
-  char device_mode = char(message[1]);
   if (this->last_qmod_) {
     this->last_qmod_->publish_state(message);
   }
+  // QMOD response is "(M" where M is the device-mode character. Bail out if the
+  // message is shorter than 2 chars (e.g. empty error response from
+  // handle_poll_error_) — reading message[1] would otherwise be out of bounds.
+  if (message[0] == '\0' || message[1] == '\0')
+    return;
   if (this->device_mode_) {
-    mode = device_mode;
+    std::string mode;
+    mode = char(message[1]);
     this->device_mode_->publish_state(mode);
   }
 }
diff --git a/esphome/components/pn532/pn532.cpp b/esphome/components/pn532/pn532.cpp
index 199a44dacc..3017b78414 100644
--- a/esphome/components/pn532/pn532.cpp
+++ b/esphome/components/pn532/pn532.cpp
@@ -317,6 +317,7 @@ enum PN532ReadReady PN532::read_ready_(bool block) {
   if (!this->rd_start_time_.has_value()) {
     this->rd_start_time_ = millis();
   }
+  const uint32_t rd_start_time = *this->rd_start_time_;
 
   while (true) {
     if (this->is_read_ready()) {
@@ -324,7 +325,7 @@ enum PN532ReadReady PN532::read_ready_(bool block) {
       break;
     }
 
-    if (millis() - *this->rd_start_time_ > 100) {
+    if (millis() - rd_start_time > 100) {
       ESP_LOGV(TAG, "Timed out waiting for readiness from PN532!");
       this->rd_ready_ = TIMEOUT;
       break;
diff --git a/esphome/components/remote_base/remote_base.h b/esphome/components/remote_base/remote_base.h
index d73fff2b0a..e5e923d780 100644
--- a/esphome/components/remote_base/remote_base.h
+++ b/esphome/components/remote_base/remote_base.h
@@ -164,7 +164,7 @@ class RemoteTransmitterBase : public RemoteComponentBase {
     return TransmitCall(this);
   }
   template<typename Protocol>
-  void transmit(const typename Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
+  void transmit(const Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
     auto call = this->transmit();
     Protocol().encode(call.get_data(), data);
     call.set_send_times(send_times);
@@ -250,10 +250,10 @@ template<typename T> class RemoteReceiverBinarySensor : public RemoteReceiverBin
   }
 
  public:
-  void set_data(typename T::ProtocolData data) { data_ = data; }
+  void set_data(T::ProtocolData data) { data_ = data; }
 
  protected:
-  typename T::ProtocolData data_;
+  T::ProtocolData data_;
 };
 
 template<typename T>
@@ -278,7 +278,7 @@ class RemoteTransmittable {
 
  protected:
   template<typename Protocol>
-  void transmit_(const typename Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
+  void transmit_(const Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
     this->transmitter_->transmit<Protocol>(data, send_times, send_wait);
   }
   RemoteTransmitterBase *transmitter_;
diff --git a/esphome/components/rp2040/__init__.py b/esphome/components/rp2040/__init__.py
index ed246416c9..79ed00cb41 100644
--- a/esphome/components/rp2040/__init__.py
+++ b/esphome/components/rp2040/__init__.py
@@ -69,6 +69,18 @@ def set_core_data(config):
 
 
 def get_download_types(storage_json):
+    """Binary-download entries for a built RP2040 firmware.
+
+    Used by:
+    - esphome.dashboard (legacy "Download .bin" button)
+    - device-builder (esphome/device-builder) — same dispatch via
+      ``importlib.import_module(f"esphome.components.{platform}")``
+      then ``module.get_download_types(storage)``. The contract is
+      "returns ``list[dict]`` with at least ``title`` /
+      ``description`` / ``file`` / ``download`` keys"; please keep
+      the shape stable so the new dashboard's download panel
+      doesn't have to special-case per-platform schemas.
+    """
     return [
         {
             "title": "UF2 factory format",
diff --git a/esphome/components/rp2040/core.cpp b/esphome/components/rp2040/core.cpp
index b7a9000612..11f23ccfef 100644
--- a/esphome/components/rp2040/core.cpp
+++ b/esphome/components/rp2040/core.cpp
@@ -1,45 +1,6 @@
 #ifdef USE_RP2040
 
-#include "core.h"
-#include "esphome/core/defines.h"
-#ifdef USE_RP2040_CRASH_HANDLER
-#include "crash_handler.h"
-#endif
-#include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
-
-#include "hardware/timer.h"
-#include "hardware/watchdog.h"
-
-namespace esphome {
-
-void HOT yield() { ::yield(); }
-uint64_t millis_64() { return micros_to_millis<uint64_t>(time_us_64()); }
-uint32_t HOT millis() { return micros_to_millis(time_us_64()); }
-void HOT delay(uint32_t ms) { ::delay(ms); }
-uint32_t HOT micros() { return ::micros(); }
-void HOT delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
-void arch_restart() {
-  watchdog_reboot(0, 0, 10);
-  while (1) {
-    continue;
-  }
-}
-
-void arch_init() {
-#ifdef USE_RP2040_CRASH_HANDLER
-  rp2040::crash_handler_read_and_clear();
-#endif
-#if USE_RP2040_WATCHDOG_TIMEOUT > 0
-  watchdog_enable(USE_RP2040_WATCHDOG_TIMEOUT, false);
-#endif
-}
-
-void HOT arch_feed_wdt() { watchdog_update(); }
-
-uint32_t HOT arch_get_cpu_cycle_count() { return ulMainGetRunTimeCounterValue(); }
-uint32_t arch_get_cpu_freq_hz() { return RP2040::f_cpu(); }
-
-}  // namespace esphome
+// HAL functions live in hal.cpp. core.cpp is intentionally empty for
+// rp2040 — there is no extra component bootstrap to keep here.
 
 #endif  // USE_RP2040
diff --git a/esphome/components/rp2040/hal.cpp b/esphome/components/rp2040/hal.cpp
new file mode 100644
index 0000000000..e71d3fd54d
--- /dev/null
+++ b/esphome/components/rp2040/hal.cpp
@@ -0,0 +1,41 @@
+#ifdef USE_RP2040
+
+#include "core.h"
+#include "esphome/core/defines.h"
+#include "esphome/core/hal.h"
+#ifdef USE_RP2040_CRASH_HANDLER
+#include "crash_handler.h"
+#endif
+
+#include "hardware/watchdog.h"
+
+// Empty rp2040 namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// rp2040 component's API.
+namespace esphome::rp2040 {}  // namespace esphome::rp2040
+
+namespace esphome {
+
+// yield(), delay(), micros(), millis(), millis_64(), delayMicroseconds(),
+// arch_feed_wdt(), arch_get_cpu_cycle_count() inlined in components/rp2040/hal.h.
+void arch_restart() {
+  watchdog_reboot(0, 0, 10);
+  while (1) {
+    continue;
+  }
+}
+
+void arch_init() {
+#ifdef USE_RP2040_CRASH_HANDLER
+  rp2040::crash_handler_read_and_clear();
+#endif
+#if USE_RP2040_WATCHDOG_TIMEOUT > 0
+  watchdog_enable(USE_RP2040_WATCHDOG_TIMEOUT, false);
+#endif
+}
+
+uint32_t arch_get_cpu_freq_hz() { return RP2040::f_cpu(); }
+
+}  // namespace esphome
+
+#endif  // USE_RP2040
diff --git a/esphome/components/rp2040/hal.h b/esphome/components/rp2040/hal.h
new file mode 100644
index 0000000000..c9c61c921d
--- /dev/null
+++ b/esphome/components/rp2040/hal.h
@@ -0,0 +1,61 @@
+#pragma once
+
+#ifdef USE_RP2040
+
+#include <cstdint>
+
+#include "esphome/core/time_conversion.h"
+
+#define IRAM_ATTR __attribute__((noinline, long_call, section(".time_critical")))
+#define PROGMEM
+
+// Forward decls from Arduino's <Arduino.h> for the inline wrappers below.
+// NOLINTBEGIN(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+extern "C" void yield(void);
+extern "C" void delay(unsigned long ms);
+extern "C" unsigned long micros(void);
+extern "C" unsigned long millis(void);
+// NOLINTEND(google-runtime-int,readability-identifier-naming,readability-redundant-declaration)
+
+// Forward decl from <pico/time.h>.
+extern "C" uint64_t time_us_64(void);
+
+// Forward decls from pico-sdk / FreeRTOS port for the inline arch_*
+// wrappers below.
+extern "C" void watchdog_update(void);
+extern "C" unsigned long ulMainGetRunTimeCounterValue(void);
+
+namespace esphome::rp2040 {}
+
+namespace esphome {
+
+// Forward decl from helpers.h.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+void delay_microseconds_safe(uint32_t us);
+
+/// Returns true when executing inside an interrupt handler.
+__attribute__((always_inline)) inline bool in_isr_context() {
+  uint32_t ipsr;
+  __asm__ volatile("mrs %0, ipsr" : "=r"(ipsr));
+  return ipsr != 0;
+}
+
+__attribute__((always_inline)) inline void yield() { ::yield(); }
+__attribute__((always_inline)) inline void delay(uint32_t ms) { ::delay(ms); }
+__attribute__((always_inline)) inline uint32_t micros() { return static_cast<uint32_t>(::micros()); }
+__attribute__((always_inline)) inline uint32_t millis() { return micros_to_millis(::time_us_64()); }
+__attribute__((always_inline)) inline uint64_t millis_64() { return micros_to_millis<uint64_t>(::time_us_64()); }
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
+__attribute__((always_inline)) inline void arch_feed_wdt() { watchdog_update(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() {
+  return static_cast<uint32_t>(ulMainGetRunTimeCounterValue());
+}
+
+void arch_init();
+uint32_t arch_get_cpu_freq_hz();
+
+}  // namespace esphome
+
+#endif  // USE_RP2040
diff --git a/esphome/components/sendspin/__init__.py b/esphome/components/sendspin/__init__.py
index b8933908a1..bdef3de93e 100644
--- a/esphome/components/sendspin/__init__.py
+++ b/esphome/components/sendspin/__init__.py
@@ -29,6 +29,7 @@ CONF_SLOT = "slot"
 
 CONF_INITIAL_STATIC_DELAY = "initial_static_delay"
 CONF_FIXED_DELAY = "fixed_delay"
+CONF_DECODE_MEMORY = "decode_memory"
 
 # sendspin-cpp library lives in the global `sendspin` namespace.
 sendspin_library_ns = cg.global_ns.namespace("sendspin")
@@ -56,6 +57,18 @@ PlayerRoleConfig = sendspin_library_ns.struct("PlayerRoleConfig")
 ArtworkRoleConfig = sendspin_library_ns.struct("ArtworkRoleConfig")
 ImageSlotPreference = sendspin_library_ns.struct("ImageSlotPreference")
 
+# MemoryLocation enum (from sendspin/types.h) controls SPIRAM-vs-internal-RAM placement
+# preference for the player role's transfer buffers.
+SendspinMemoryLocation = sendspin_library_ns.enum("MemoryLocation", is_class=True)
+
+MEMORY_PSRAM = "psram"
+MEMORY_INTERNAL = "internal"
+MEMORY_LOCATIONS = [MEMORY_PSRAM, MEMORY_INTERNAL]
+MEMORY_LOCATION_ENUM = {
+    MEMORY_PSRAM: SendspinMemoryLocation.PREFER_EXTERNAL,
+    MEMORY_INTERNAL: SendspinMemoryLocation.PREFER_INTERNAL,
+}
+
 # Trailing underscore avoids clashing with sendspin-cpp's global `sendspin` namespace.
 # Analysis tools strip the trailing underscore (same pattern as `template_`).
 sendspin_ns = cg.esphome_ns.namespace("sendspin_")
@@ -217,7 +230,7 @@ async def to_code(config: ConfigType) -> None:
         )
 
     # sendspin-cpp library
-    esp32.add_idf_component(name="sendspin/sendspin-cpp", ref="0.3.1")
+    esp32.add_idf_component(name="sendspin/sendspin-cpp", ref="0.4.0")
 
     cg.add_define("USE_SENDSPIN", True)  # for MDNS
 
@@ -294,14 +307,23 @@ async def to_code(config: ConfigType) -> None:
                 "CONFIG_SPIRAM_ALLOW_STACK_EXTERNAL_MEMORY", True
             )
 
-        player_config_struct = cg.StructInitializer(
-            PlayerRoleConfig,
+        # Library defaults: priority 18 (one above httpd_priority 17 so the decoder is not
+        # starved by the HTTP server during the initial encoded-audio burst at stream start),
+        # interpolation/decode buffer locations PREFER_EXTERNAL.
+        player_struct_fields = [
             ("audio_formats", audio_format_structs),
             ("audio_buffer_capacity", player_cfg[CONF_BUFFER_SIZE]),
             ("fixed_delay_us", player_cfg[CONF_FIXED_DELAY]),
             ("initial_static_delay_ms", player_cfg[CONF_INITIAL_STATIC_DELAY]),
             ("psram_stack", psram_stack),
-            ("priority", 2),
+        ]
+        if (decode_memory := player_cfg.get(CONF_DECODE_MEMORY)) is not None:
+            player_struct_fields.append(
+                ("decode_buffer_location", MEMORY_LOCATION_ENUM[decode_memory])
+            )
+        player_config_struct = cg.StructInitializer(
+            PlayerRoleConfig,
+            *player_struct_fields,
         )
         cg.add(var.set_player_config(player_config_struct))
     else:
diff --git a/esphome/components/sendspin/media_source/__init__.py b/esphome/components/sendspin/media_source/__init__.py
index 6d61a8a636..f689ab01cb 100644
--- a/esphome/components/sendspin/media_source/__init__.py
+++ b/esphome/components/sendspin/media_source/__init__.py
@@ -13,9 +13,11 @@ from esphome.cpp_generator import MockObj, TemplateArgsType
 from esphome.types import ConfigType
 
 from .. import (
+    CONF_DECODE_MEMORY,
     CONF_FIXED_DELAY,
     CONF_INITIAL_STATIC_DELAY,
     CONF_SENDSPIN_ID,
+    MEMORY_LOCATIONS,
     SendspinHub,
     _validate_task_stack_in_psram,
     register_player_config,
@@ -57,6 +59,7 @@ def _register(config: ConfigType) -> ConfigType:
             CONF_INITIAL_STATIC_DELAY: config[CONF_INITIAL_STATIC_DELAY],
             CONF_FIXED_DELAY: config[CONF_FIXED_DELAY],
             CONF_TASK_STACK_IN_PSRAM: config.get(CONF_TASK_STACK_IN_PSRAM, False),
+            CONF_DECODE_MEMORY: config.get(CONF_DECODE_MEMORY),
         }
     )
     return config
@@ -82,6 +85,7 @@ CONFIG_SCHEMA = cv.All(
             cv.Optional(CONF_SAMPLE_RATE, default=48000): cv.int_range(
                 min=16000, max=96000
             ),
+            cv.Optional(CONF_DECODE_MEMORY): cv.one_of(*MEMORY_LOCATIONS, lower=True),
         }
     ),
     cv.only_on_esp32,
diff --git a/esphome/components/sensor/__init__.py b/esphome/components/sensor/__init__.py
index 48b7d25d4d..ed02cc2543 100644
--- a/esphome/components/sensor/__init__.py
+++ b/esphome/components/sensor/__init__.py
@@ -266,7 +266,7 @@ StreamingMovingAverageFilter = sensor_ns.class_("StreamingMovingAverageFilter",
 ExponentialMovingAverageFilter = sensor_ns.class_(
     "ExponentialMovingAverageFilter", Filter
 )
-ThrottleAverageFilter = sensor_ns.class_("ThrottleAverageFilter", Filter, cg.Component)
+ThrottleAverageFilter = sensor_ns.class_("ThrottleAverageFilter", Filter)
 LambdaFilter = sensor_ns.class_("LambdaFilter", Filter)
 StatelessLambdaFilter = sensor_ns.class_("StatelessLambdaFilter", Filter)
 OffsetFilter = sensor_ns.class_("OffsetFilter", Filter)
@@ -283,8 +283,8 @@ ThrottleWithPriorityNanFilter = sensor_ns.class_(
 TimeoutFilterBase = sensor_ns.class_("TimeoutFilterBase", Filter, cg.Component)
 TimeoutFilterLast = sensor_ns.class_("TimeoutFilterLast", TimeoutFilterBase)
 TimeoutFilterConfigured = sensor_ns.class_("TimeoutFilterConfigured", TimeoutFilterBase)
-DebounceFilter = sensor_ns.class_("DebounceFilter", Filter, cg.Component)
-HeartbeatFilter = sensor_ns.class_("HeartbeatFilter", Filter, cg.Component)
+DebounceFilter = sensor_ns.class_("DebounceFilter", Filter)
+HeartbeatFilter = sensor_ns.class_("HeartbeatFilter", Filter)
 DeltaFilter = sensor_ns.class_("DeltaFilter", Filter)
 OrFilter = sensor_ns.class_("OrFilter", Filter)
 CalibrateLinearFilter = sensor_ns.class_("CalibrateLinearFilter", Filter)
@@ -564,12 +564,15 @@ async def exponential_moving_average_filter_to_code(config, filter_id):
 
 
 @FILTER_REGISTRY.register(
-    "throttle_average", ThrottleAverageFilter, cv.positive_time_period_milliseconds
+    "throttle_average",
+    ThrottleAverageFilter,
+    cv.All(
+        cv.positive_time_period_milliseconds,
+        cv.Range(max=cv.TimePeriod(hours=24)),
+    ),
 )
 async def throttle_average_filter_to_code(config, filter_id):
-    var = cg.new_Pvariable(filter_id, config)
-    await cg.register_component(var, {})
-    return var
+    return cg.new_Pvariable(filter_id, config)
 
 
 @FILTER_REGISTRY.register("lambda", LambdaFilter, cv.returning_lambda)
@@ -698,13 +701,10 @@ HEARTBEAT_SCHEMA = cv.Schema(
 async def heartbeat_filter_to_code(config, filter_id):
     if isinstance(config, dict):
         var = cg.new_Pvariable(filter_id, config[CONF_PERIOD])
-        await cg.register_component(var, {})
         cg.add(var.set_optimistic(config[CONF_OPTIMISTIC]))
         return var
 
-    var = cg.new_Pvariable(filter_id, config)
-    await cg.register_component(var, {})
-    return var
+    return cg.new_Pvariable(filter_id, config)
 
 
 TIMEOUT_SCHEMA = cv.maybe_simple_value(
@@ -738,9 +738,7 @@ async def timeout_filter_to_code(config, filter_id):
     "debounce", DebounceFilter, cv.positive_time_period_milliseconds
 )
 async def debounce_filter_to_code(config, filter_id):
-    var = cg.new_Pvariable(filter_id, config)
-    await cg.register_component(var, {})
-    return var
+    return cg.new_Pvariable(filter_id, config)
 
 
 CONF_DATAPOINTS = "datapoints"
diff --git a/esphome/components/sensor/filter.cpp b/esphome/components/sensor/filter.cpp
index 4896757d3f..5f7f19769a 100644
--- a/esphome/components/sensor/filter.cpp
+++ b/esphome/components/sensor/filter.cpp
@@ -13,11 +13,6 @@ namespace esphome::sensor {
 
 static const char *const TAG = "sensor.filter";
 
-// Filter scheduler IDs.
-// Each filter is its own Component instance, so the scheduler scopes
-// IDs by component pointer — no risk of collisions between instances.
-constexpr uint32_t FILTER_ID = 0;
-
 // Filter
 void Filter::input(float value) {
   ESP_LOGVV(TAG, "Filter(%p)::input(%f)", this, value);
@@ -185,8 +180,9 @@ optional<float> ThrottleAverageFilter::new_value(float value) {
   }
   return {};
 }
-void ThrottleAverageFilter::setup() {
-  this->set_interval(FILTER_ID, this->time_period_, [this]() {
+void ThrottleAverageFilter::initialize(Sensor *parent, Filter *next) {
+  Filter::initialize(parent, next);
+  App.scheduler.set_interval(this, this->time_period_, [this]() {
     ESP_LOGVV(TAG, "ThrottleAverageFilter(%p)::interval(sum=%f, n=%i)", this, this->sum_, this->n_);
     if (this->n_ == 0) {
       if (this->have_nan_)
@@ -199,7 +195,6 @@ void ThrottleAverageFilter::setup() {
     this->have_nan_ = false;
   });
 }
-float ThrottleAverageFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
 
 // LambdaFilter
 LambdaFilter::LambdaFilter(lambda_filter_t lambda_filter) : lambda_filter_(std::move(lambda_filter)) {}
@@ -362,13 +357,12 @@ optional<float> TimeoutFilterConfigured::new_value(float value) {
 
 // DebounceFilter
 optional<float> DebounceFilter::new_value(float value) {
-  this->set_timeout(FILTER_ID, this->time_period_, [this, value]() { this->output(value); });
+  App.scheduler.set_timeout(this, this->time_period_, [this, value]() { this->output(value); });
 
   return {};
 }
 
 DebounceFilter::DebounceFilter(uint32_t time_period) : time_period_(time_period) {}
-float DebounceFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
 
 // HeartbeatFilter
 HeartbeatFilter::HeartbeatFilter(uint32_t time_period) : time_period_(time_period), last_input_(NAN) {}
@@ -384,8 +378,9 @@ optional<float> HeartbeatFilter::new_value(float value) {
   return {};
 }
 
-void HeartbeatFilter::setup() {
-  this->set_interval(FILTER_ID, this->time_period_, [this]() {
+void HeartbeatFilter::initialize(Sensor *parent, Filter *next) {
+  Filter::initialize(parent, next);
+  App.scheduler.set_interval(this, this->time_period_, [this]() {
     ESP_LOGVV(TAG, "HeartbeatFilter(%p)::interval(has_value=%s, last_input=%f)", this, YESNO(this->has_value_),
               this->last_input_);
     if (!this->has_value_)
@@ -395,8 +390,6 @@ void HeartbeatFilter::setup() {
   });
 }
 
-float HeartbeatFilter::get_setup_priority() const { return setup_priority::HARDWARE; }
-
 optional<float> calibrate_linear_compute(const std::array<float, 3> *functions, size_t count, float value) {
   for (size_t i = 0; i < count; i++) {
     if (!std::isfinite(functions[i][2]) || value < functions[i][2])
diff --git a/esphome/components/sensor/filter.h b/esphome/components/sensor/filter.h
index 917a1ce7d5..b79bfa17d6 100644
--- a/esphome/components/sensor/filter.h
+++ b/esphome/components/sensor/filter.h
@@ -254,21 +254,22 @@ class ExponentialMovingAverageFilter : public Filter {
  *
  * It takes the average of all the values received in a period of time.
  */
-class ThrottleAverageFilter : public Filter, public Component {
+class ThrottleAverageFilter : public Filter {
  public:
   explicit ThrottleAverageFilter(uint32_t time_period);
 
-  void setup() override;
+  void initialize(Sensor *parent, Filter *next) override;
 
   optional<float> new_value(float value) override;
 
-  float get_setup_priority() const override;
-
  protected:
   float sum_{0.0f};
-  unsigned int n_{0};
   uint32_t time_period_;
-  bool have_nan_{false};
+  // Sample count packed with NaN-seen flag in a single 32-bit word.
+  // n_ is bounded by YAML cap on time_period_ (24 h) × max plausible source
+  // rate (1 kHz) = 86.4M ≪ 2^31, so 31 bits has 25x headroom.
+  uint32_t n_ : 31 {0};
+  uint32_t have_nan_ : 1 {0};
 };
 
 using lambda_filter_t = std::function<optional<float>(float)>;
@@ -412,7 +413,31 @@ class ThrottleWithPriorityNanFilter : public Filter {
   uint32_t min_time_between_inputs_;
 };
 
-// Base class for timeout filters - contains common loop logic
+// Base class for timeout filters - contains common loop logic.
+//
+// Why this intentionally inherits Component (and does NOT use the self-keyed
+// `App.scheduler.set_timeout(this, ...)` pattern that the other Filter classes
+// migrated to):
+//
+// Timeout filters re-arm on every input, so on devices with many sensors
+// using timeout filters (e.g. multi-LD2450 boards) every armed filter would
+// require a live SchedulerItem in RAM at the same time. A SchedulerItem is
+// substantially larger than the Component bookkeeping bytes carried by this
+// class, so paying the Component cost per filter (one-time, BSS) is cheaper
+// than paying for a SchedulerItem per filter (live, while armed). #11922
+// is the original symptom and switchover to the loop-based design; #16173
+// attempted to migrate this onto the scheduler and was closed for exactly
+// this reason — even if the scheduler pool were unbounded, RAM per armed
+// filter would still be dominated by the SchedulerItem itself, not by
+// anything we can shrink in the scheduler.
+//
+// The loop-based design has additional advantages on top of the RAM win:
+// `enable_loop()` / `disable_loop()` partitions the cost away when no
+// timeout is armed; while armed, work is a single timestamp compare per
+// active filter, with no per-input scheduler cancel/insert path.
+//
+// Don't try to migrate this class onto the self-keyed scheduler. The math
+// doesn't work — at scale, this design is the smaller one.
 class TimeoutFilterBase : public Filter, public Component {
  public:
   void loop() override;
@@ -454,25 +479,22 @@ class TimeoutFilterConfigured : public TimeoutFilterBase {
   // Total: 8 (base) + 4 = 12 bytes + vtable ptr + Component overhead
 };
 
-class DebounceFilter : public Filter, public Component {
+class DebounceFilter : public Filter {
  public:
   explicit DebounceFilter(uint32_t time_period);
 
   optional<float> new_value(float value) override;
 
-  float get_setup_priority() const override;
-
  protected:
   uint32_t time_period_;
 };
 
-class HeartbeatFilter : public Filter, public Component {
+class HeartbeatFilter : public Filter {
  public:
   explicit HeartbeatFilter(uint32_t time_period);
 
-  void setup() override;
+  void initialize(Sensor *parent, Filter *next) override;
   optional<float> new_value(float value) override;
-  float get_setup_priority() const override;
 
   void set_optimistic(bool optimistic) { this->optimistic_ = optimistic; }
 
diff --git a/esphome/components/sim800l/sim800l.cpp b/esphome/components/sim800l/sim800l.cpp
index 913d920c94..001ec77454 100644
--- a/esphome/components/sim800l/sim800l.cpp
+++ b/esphome/components/sim800l/sim800l.cpp
@@ -110,7 +110,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
     case STATE_INIT: {
       // While we were waiting for update to check for messages, this notifies a message
       // is available.
-      bool message_available = message.compare(0, 6, "+CMTI:") == 0;
+      bool message_available = message.starts_with("+CMTI:");
       if (!message_available) {
         if (message == "RING") {
           // Incoming call...
@@ -120,7 +120,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
             this->call_state_ = 6;
             this->call_disconnected_callback_.call();
           }
-        } else if (message.compare(0, 6, "+CUSD:") == 0) {
+        } else if (message.starts_with("+CUSD:")) {
           // Incoming USSD MESSAGE
           this->state_ = STATE_CHECK_USSD;
         }
@@ -175,7 +175,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       break;
     case STATE_CHECK_USSD:
       ESP_LOGD(TAG, "Check ussd code: '%s'", message.c_str());
-      if (message.compare(0, 6, "+CUSD:") == 0) {
+      if (message.starts_with("+CUSD:")) {
         this->state_ = STATE_RECEIVED_USSD;
         this->ussd_ = "";
         size_t start = 10;
@@ -196,8 +196,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
     case STATE_CREG_WAIT: {
       // Response: "+CREG: 0,1" -- the one there means registered ok
       //           "+CREG: -,-" means not registered ok
-      bool registered =
-          message.size() > 9 && message.compare(0, 6, "+CREG:") == 0 && (message[9] == '1' || message[9] == '5');
+      bool registered = message.size() > 9 && message.starts_with("+CREG:") && (message[9] == '1' || message[9] == '5');
       if (registered) {
         if (!this->registered_) {
           ESP_LOGD(TAG, "Registered OK");
@@ -223,7 +222,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       this->state_ = STATE_CSQ_RESPONSE;
       break;
     case STATE_CSQ_RESPONSE:
-      if (message.compare(0, 5, "+CSQ:") == 0) {
+      if (message.starts_with("+CSQ:")) {
         size_t comma = message.find(',', 6);
         if (comma != 6) {
           int rssi = parse_number<int>(message.substr(6, comma - 6)).value_or(0);
@@ -243,7 +242,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       this->state_ = STATE_CHECK_SMS;
       break;
     case STATE_PARSE_SMS_RESPONSE:
-      if (message.compare(0, 6, "+CMGL:") == 0 && this->parse_index_ == 0) {
+      if (message.starts_with("+CMGL:") && this->parse_index_ == 0) {
         size_t start = 7;
         size_t end = message.find(',', start);
         uint8_t item = 0;
@@ -278,7 +277,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       }
       break;
     case STATE_CHECK_CALL:
-      if (message.compare(0, 6, "+CLCC:") == 0 && this->parse_index_ == 0) {
+      if (message.starts_with("+CLCC:") && this->parse_index_ == 0) {
         this->expect_ack_ = true;
         size_t start = 7;
         size_t end = message.find(',', start);
@@ -324,7 +323,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       /* Our recipient is set and the message body is in message
         kick ESPHome callback now
       */
-      if (ok || message.compare(0, 6, "+CMGL:") == 0) {
+      if (ok || message.starts_with("+CMGL:")) {
         ESP_LOGD(TAG,
                  "Received SMS from: %s\n"
                  "  %s",
@@ -360,7 +359,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       }
       break;
     case STATE_SENDING_SMS_3:
-      if (message.compare(0, 6, "+CMGS:") == 0) {
+      if (message.starts_with("+CMGS:")) {
         ESP_LOGD(TAG, "SMS Sent OK: %s", message.c_str());
         this->send_pending_ = false;
         this->state_ = STATE_CHECK_SMS;
@@ -383,7 +382,7 @@ void Sim800LComponent::parse_cmd_(std::string message) {
       this->state_ = STATE_INIT;
       break;
     case STATE_PARSE_CLIP:
-      if (message.compare(0, 6, "+CLIP:") == 0) {
+      if (message.starts_with("+CLIP:")) {
         std::string caller_id;
         size_t start = 7;
         size_t end = message.find(',', start);
diff --git a/esphome/components/speaker/media_player/__init__.py b/esphome/components/speaker/media_player/__init__.py
index abfd599808..fbc83ef12f 100644
--- a/esphome/components/speaker/media_player/__init__.py
+++ b/esphome/components/speaker/media_player/__init__.py
@@ -1,5 +1,6 @@
 """Speaker Media Player Setup."""
 
+from functools import partial
 import hashlib
 import logging
 from pathlib import Path
@@ -32,7 +33,7 @@ from esphome.const import (
     CONF_URL,
 )
 from esphome.core import CORE, HexInt
-from esphome.external_files import download_content
+from esphome.external_files import download_web_files_in_config
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -92,15 +93,6 @@ def _compute_local_file_path(value: dict) -> Path:
     return base_dir / key
 
 
-def _download_web_file(value):
-    url = value[CONF_URL]
-    path = _compute_local_file_path(value)
-
-    download_content(url, path)
-    _LOGGER.debug("download_web_file: path=%s", path)
-    return value
-
-
 _PURPOSE_MAP = {
     "MEDIA": media_player.MEDIA_PLAYER_FORMAT_PURPOSE_ENUM["default"],
     "ANNOUNCEMENT": media_player.MEDIA_PLAYER_FORMAT_PURPOSE_ENUM["announcement"],
@@ -229,11 +221,10 @@ LOCAL_SCHEMA = cv.Schema(
     }
 )
 
-WEB_SCHEMA = cv.All(
+WEB_SCHEMA = cv.Schema(
     {
         cv.Required(CONF_URL): cv.url,
-    },
-    _download_web_file,
+    }
 )
 
 
@@ -285,7 +276,12 @@ CONFIG_SCHEMA = cv.All(
             ),
             # Remove before 2026.10.0
             cv.Optional(CONF_CODEC_SUPPORT_ENABLED): cv.Any(cv.boolean, cv.string),
-            cv.Optional(CONF_FILES): cv.ensure_list(MEDIA_FILE_TYPE_SCHEMA),
+            cv.Optional(CONF_FILES): cv.All(
+                cv.ensure_list(MEDIA_FILE_TYPE_SCHEMA),
+                partial(
+                    download_web_files_in_config, path_for=_compute_local_file_path
+                ),
+            ),
             cv.Optional(CONF_TASK_STACK_IN_PSRAM): cv.All(
                 cv.boolean, cv.requires_component(psram.DOMAIN)
             ),
diff --git a/esphome/components/speaker/media_player/speaker_media_player.cpp b/esphome/components/speaker/media_player/speaker_media_player.cpp
index 930373c6fc..ab11a89c3f 100644
--- a/esphome/components/speaker/media_player/speaker_media_player.cpp
+++ b/esphome/components/speaker/media_player/speaker_media_player.cpp
@@ -502,7 +502,7 @@ void SpeakerMediaPlayer::control(const media_player::MediaPlayerCall &call) {
     media_command.announce = false;
   }
 
-  auto media_url = call.get_media_url();
+  const auto &media_url = call.get_media_url();
   if (media_url.has_value()) {
     media_command.url =
         new std::string(*media_url);  // Must be manually deleted after receiving media_command from a queue
diff --git a/esphome/components/speaker_source/speaker_source_media_player.cpp b/esphome/components/speaker_source/speaker_source_media_player.cpp
index 2caab828fb..87fd4fe9ed 100644
--- a/esphome/components/speaker_source/speaker_source_media_player.cpp
+++ b/esphome/components/speaker_source/speaker_source_media_player.cpp
@@ -698,7 +698,7 @@ void SpeakerSourceMediaPlayer::control(const media_player::MediaPlayerCall &call
     }
   }
 
-  auto media_url = call.get_media_url();
+  const auto &media_url = call.get_media_url();
   if (media_url.has_value()) {
     auto command = call.get_command();
     bool enqueue = command.has_value() && command.value() == media_player::MEDIA_PLAYER_COMMAND_ENQUEUE;
diff --git a/esphome/components/spi/spi.h b/esphome/components/spi/spi.h
index dc538f4c41..e6f592c6e4 100644
--- a/esphome/components/spi/spi.h
+++ b/esphome/components/spi/spi.h
@@ -451,7 +451,7 @@ class SPIDevice : public SPIClient {
 
   uint8_t read_byte() { return this->delegate_->transfer(0); }
 
-  void read_array(uint8_t *data, size_t length) { return this->delegate_->read_array(data, length); }
+  void read_array(uint8_t *data, size_t length) { this->delegate_->read_array(data, length); }
 
   /**
    * Write a single data item, up to 32 bits.
diff --git a/esphome/components/sprinkler/sprinkler.cpp b/esphome/components/sprinkler/sprinkler.cpp
index 0802cdec8e..336123a472 100644
--- a/esphome/components/sprinkler/sprinkler.cpp
+++ b/esphome/components/sprinkler/sprinkler.cpp
@@ -669,7 +669,7 @@ uint32_t Sprinkler::valve_run_duration_adjusted(const size_t valve_number) {
   // run_duration must not be less than any of these
   if ((run_duration < this->start_delay_) || (run_duration < this->stop_delay_) ||
       (run_duration < this->switching_delay_.value_or(0) * 2)) {
-    return std::max(this->switching_delay_.value_or(0) * 2, std::max(this->start_delay_, this->stop_delay_));
+    return std::max({this->switching_delay_.value_or(0) * 2, this->start_delay_, this->stop_delay_});
   }
   return run_duration;
 }
@@ -897,11 +897,12 @@ void Sprinkler::resume() {
   }
 
   if (this->paused_valve_.has_value() && (this->resume_duration_.has_value())) {
+    const size_t paused_valve = *this->paused_valve_;
+    const uint32_t resume_duration = *this->resume_duration_;
     // Resume only if valve has not been completed yet
-    if (!this->valve_cycle_complete_(this->paused_valve_.value())) {
-      ESP_LOGD(TAG, "Resuming valve %zu with %" PRIu32 " seconds remaining", this->paused_valve_.value_or(0),
-               this->resume_duration_.value_or(0));
-      this->fsm_request_(this->paused_valve_.value(), this->resume_duration_.value());
+    if (!this->valve_cycle_complete_(paused_valve)) {
+      ESP_LOGD(TAG, "Resuming valve %zu with %" PRIu32 " seconds remaining", paused_valve, resume_duration);
+      this->fsm_request_(paused_valve, resume_duration);
     }
     this->reset_resume();
   } else {
diff --git a/esphome/components/st7789v/__init__.py b/esphome/components/st7789v/__init__.py
index 3e64d09c57..7915cf119c 100644
--- a/esphome/components/st7789v/__init__.py
+++ b/esphome/components/st7789v/__init__.py
@@ -1,3 +1,8 @@
 import esphome.codegen as cg
 
 st7789v_ns = cg.esphome_ns.namespace("st7789v")
+
+DEPRECATED_COMPONENT = """
+The 'st7789v' component is deprecated and no new functionality will be added to it.
+PRs should target the newer and more performant 'mipi_spi' component.
+"""
diff --git a/esphome/components/st7789v/display.py b/esphome/components/st7789v/display.py
index 745c37f47d..3b4d6d99ea 100644
--- a/esphome/components/st7789v/display.py
+++ b/esphome/components/st7789v/display.py
@@ -1,3 +1,5 @@
+import logging
+
 from esphome import pins
 import esphome.codegen as cg
 from esphome.components import display, power_supply, spi
@@ -26,6 +28,8 @@ CODEOWNERS = ["@kbx81"]
 
 DEPENDENCIES = ["spi"]
 
+LOGGER = logging.getLogger(__name__)
+
 ST7789V = st7789v_ns.class_(
     "ST7789V", cg.PollingComponent, spi.SPIDevice, display.DisplayBuffer
 )
@@ -175,6 +179,9 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 
 
 async def to_code(config):
+    LOGGER.warning(
+        "The 'st7789v' component is deprecated, it is recommended to use 'mipi_spi' instead."
+    )
     var = cg.new_Pvariable(config[CONF_ID])
     await display.register_display(var, config)
     await spi.register_spi_device(var, config, write_only=True)
diff --git a/esphome/components/sx126x/__init__.py b/esphome/components/sx126x/__init__.py
index b8696158fe..a4ba5c34f3 100644
--- a/esphome/components/sx126x/__init__.py
+++ b/esphome/components/sx126x/__init__.py
@@ -1,3 +1,5 @@
+from typing import Any
+
 from esphome import automation, pins
 import esphome.codegen as cg
 from esphome.components import spi
@@ -5,6 +7,8 @@ from esphome.components.const import CONF_CRC_ENABLE, CONF_ON_PACKET
 import esphome.config_validation as cv
 from esphome.const import CONF_BUSY_PIN, CONF_DATA, CONF_FREQUENCY, CONF_ID
 from esphome.core import ID, TimePeriod
+from esphome.cpp_generator import MockObj
+from esphome.types import ConfigType, TemplateArgsType
 
 MULTI_CONF = True
 CODEOWNERS = ["@swoboda1337"]
@@ -15,6 +19,7 @@ CONF_SX126X_ID = "sx126x_id"
 CONF_BANDWIDTH = "bandwidth"
 CONF_BITRATE = "bitrate"
 CONF_CODING_RATE = "coding_rate"
+CONF_COLD = "cold"
 CONF_CRC_INVERTED = "crc_inverted"
 CONF_CRC_SIZE = "crc_size"
 CONF_CRC_POLYNOMIAL = "crc_polynomial"
@@ -144,7 +149,7 @@ SetModeStandbyAction = sx126x_ns.class_(
 )
 
 
-def validate_raw_data(value):
+def validate_raw_data(value: Any) -> bytes | list[int]:
     if isinstance(value, str):
         return value.encode("utf-8")
     if isinstance(value, list):
@@ -154,7 +159,7 @@ def validate_raw_data(value):
     )
 
 
-def validate_config(config):
+def validate_config(config: ConfigType) -> ConfigType:
     lora_bws = [
         "7_8kHz",
         "10_4kHz",
@@ -235,7 +240,7 @@ CONFIG_SCHEMA = (
 )
 
 
-async def to_code(config):
+async def to_code(config: ConfigType) -> None:
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
     await spi.register_spi_device(var, config)
@@ -307,24 +312,50 @@ NO_ARGS_ACTION_SCHEMA = automation.maybe_simple_id(
     NO_ARGS_ACTION_SCHEMA,
     synchronous=True,
 )
-@automation.register_action(
-    "sx126x.set_mode_sleep",
-    SetModeSleepAction,
-    NO_ARGS_ACTION_SCHEMA,
-    synchronous=True,
-)
 @automation.register_action(
     "sx126x.set_mode_standby",
     SetModeStandbyAction,
     NO_ARGS_ACTION_SCHEMA,
     synchronous=True,
 )
-async def no_args_action_to_code(config, action_id, template_arg, args):
+async def no_args_action_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
     var = cg.new_Pvariable(action_id, template_arg)
     await cg.register_parented(var, config[CONF_ID])
     return var
 
 
+SET_MODE_SLEEP_ACTION_SCHEMA = automation.maybe_simple_id(
+    {
+        cv.GenerateID(): cv.use_id(SX126x),
+        cv.Optional(CONF_COLD, default=False): cv.templatable(cv.boolean),
+    }
+)
+
+
+@automation.register_action(
+    "sx126x.set_mode_sleep",
+    SetModeSleepAction,
+    SET_MODE_SLEEP_ACTION_SCHEMA,
+    synchronous=True,
+)
+async def set_mode_sleep_action_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
+    var = cg.new_Pvariable(action_id, template_arg)
+    await cg.register_parented(var, config[CONF_ID])
+    template_ = await cg.templatable(config[CONF_COLD], args, bool)
+    cg.add(var.set_cold(template_))
+    return var
+
+
 SEND_PACKET_ACTION_SCHEMA = cv.maybe_simple_value(
     {
         cv.GenerateID(): cv.use_id(SX126x),
@@ -340,7 +371,12 @@ SEND_PACKET_ACTION_SCHEMA = cv.maybe_simple_value(
     SEND_PACKET_ACTION_SCHEMA,
     synchronous=True,
 )
-async def send_packet_action_to_code(config, action_id, template_arg, args):
+async def send_packet_action_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
     var = cg.new_Pvariable(action_id, template_arg)
     await cg.register_parented(var, config[CONF_ID])
     data = config[CONF_DATA]
diff --git a/esphome/components/sx126x/automation.h b/esphome/components/sx126x/automation.h
index 2282c583cb..ed5986e097 100644
--- a/esphome/components/sx126x/automation.h
+++ b/esphome/components/sx126x/automation.h
@@ -56,7 +56,8 @@ template<typename... Ts> class SetModeRxAction : public Action<Ts...>, public Pa
 
 template<typename... Ts> class SetModeSleepAction : public Action<Ts...>, public Parented<SX126x> {
  public:
-  void play(const Ts &...x) override { this->parent_->set_mode_sleep(); }
+  TEMPLATABLE_VALUE(bool, cold)
+  void play(const Ts &...x) override { this->parent_->set_mode_sleep(this->cold_.value(x...)); }
 };
 
 template<typename... Ts> class SetModeStandbyAction : public Action<Ts...>, public Parented<SX126x> {
diff --git a/esphome/components/sx126x/sx126x.cpp b/esphome/components/sx126x/sx126x.cpp
index 6ea09e3a9e..02f7d972a9 100644
--- a/esphome/components/sx126x/sx126x.cpp
+++ b/esphome/components/sx126x/sx126x.cpp
@@ -459,9 +459,10 @@ void SX126x::set_mode_tx() {
   this->write_opcode_(RADIO_SET_TX, buf, 3);
 }
 
-void SX126x::set_mode_sleep() {
+void SX126x::set_mode_sleep(bool cold) {
+  // 0x04 = warm start (config retained), 0x00 = cold start (config lost, lowest power)
   uint8_t buf[1];
-  buf[0] = 0x05;
+  buf[0] = cold ? 0x00 : 0x04;
   this->write_opcode_(RADIO_SET_SLEEP, buf, 1);
 }
 
diff --git a/esphome/components/sx126x/sx126x.h b/esphome/components/sx126x/sx126x.h
index edc00e3727..87bbf18c79 100644
--- a/esphome/components/sx126x/sx126x.h
+++ b/esphome/components/sx126x/sx126x.h
@@ -79,7 +79,7 @@ class SX126x : public Component,
   void set_mode_rx();
   void set_mode_tx();
   void set_mode_standby(SX126xStandbyMode mode);
-  void set_mode_sleep();
+  void set_mode_sleep(bool cold = false);
   void set_modulation(uint8_t modulation) { this->modulation_ = modulation; }
   void set_pa_power(int8_t power) { this->pa_power_ = power; }
   void set_pa_ramp(uint8_t ramp) { this->pa_ramp_ = ramp; }
diff --git a/esphome/components/template/cover/__init__.py b/esphome/components/template/cover/__init__.py
index a30c0af313..7cb50df84c 100644
--- a/esphome/components/template/cover/__init__.py
+++ b/esphome/components/template/cover/__init__.py
@@ -19,6 +19,9 @@ from esphome.const import (
     CONF_TILT_ACTION,
     CONF_TILT_LAMBDA,
 )
+from esphome.core import ID
+from esphome.cpp_generator import MockObj
+from esphome.types import ConfigType, TemplateArgsType
 
 from .. import template_ns
 
@@ -110,6 +113,16 @@ async def to_code(config):
     cg.add(var.set_restore_mode(config[CONF_RESTORE_MODE]))
 
 
+# CONF_STATE and CONF_POSITION are cv.Exclusive in the schema, so at most
+# one is present and both map to the position field.
+_COVER_PUBLISH_FIELDS: tuple[cover.ApplyField, ...] = (
+    cover.ApplyField(CONF_STATE, "position", cg.float_),
+    cover.ApplyField(CONF_POSITION, "position", cg.float_),
+    cover.ApplyField(CONF_TILT, "tilt", cg.float_),
+    cover.ApplyField(CONF_CURRENT_OPERATION, "current_operation", cover.CoverOperation),
+)
+
+
 @automation.register_action(
     "cover.template.publish",
     cover.CoverPublishAction,
@@ -126,21 +139,20 @@ async def to_code(config):
     ),
     synchronous=True,
 )
-async def cover_template_publish_to_code(config, action_id, template_arg, args):
-    paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if CONF_STATE in config:
-        template_ = await cg.templatable(config[CONF_STATE], args, cg.float_)
-        cg.add(var.set_position(template_))
-    if CONF_POSITION in config:
-        template_ = await cg.templatable(config[CONF_POSITION], args, cg.float_)
-        cg.add(var.set_position(template_))
-    if CONF_TILT in config:
-        template_ = await cg.templatable(config[CONF_TILT], args, cg.float_)
-        cg.add(var.set_tilt(template_))
-    if CONF_CURRENT_OPERATION in config:
-        template_ = await cg.templatable(
-            config[CONF_CURRENT_OPERATION], args, cover.CoverOperation
-        )
-        cg.add(var.set_current_operation(template_))
-    return var
+async def cover_template_publish_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
+    # Mutates Cover fields directly (no CoverCall) since publish is a state
+    # push, not a control request.
+    return await cover.build_apply_lambda_action(
+        config=config,
+        action_id=action_id,
+        template_arg=template_arg,
+        args=args,
+        fields=_COVER_PUBLISH_FIELDS,
+        prefix_args=[(cover.Cover.operator("ptr"), "cover")],
+        statement_fn=lambda field, expr: f"cover->{field} = {expr};",
+    )
diff --git a/esphome/components/time/automation.cpp b/esphome/components/time/automation.cpp
index 7eb99cfe74..3242669343 100644
--- a/esphome/components/time/automation.cpp
+++ b/esphome/components/time/automation.cpp
@@ -31,13 +31,14 @@ void CronTrigger::check_time_() {
     return;
 
   if (this->last_check_.has_value()) {
-    if (*this->last_check_ > time && this->last_check_->timestamp - time.timestamp > MAX_TIMESTAMP_DRIFT) {
+    auto &last_check = *this->last_check_;
+    if (last_check > time && last_check.timestamp - time.timestamp > MAX_TIMESTAMP_DRIFT) {
       // We went back in time (a lot), probably caused by time synchronization
       ESP_LOGW(TAG, "Time has jumped back!");
-    } else if (*this->last_check_ >= time) {
+    } else if (last_check >= time) {
       // already handled this one
       return;
-    } else if (time > *this->last_check_ && time.timestamp - this->last_check_->timestamp > MAX_TIMESTAMP_DRIFT) {
+    } else if (time > last_check && time.timestamp - last_check.timestamp > MAX_TIMESTAMP_DRIFT) {
       // We went ahead in time (a lot), probably caused by time synchronization
       ESP_LOGW(TAG, "Time has jumped ahead!");
       this->last_check_ = time;
@@ -45,11 +46,11 @@ void CronTrigger::check_time_() {
     }
 
     while (true) {
-      this->last_check_->increment_second();
-      if (*this->last_check_ >= time)
+      last_check.increment_second();
+      if (last_check >= time)
         break;
 
-      if (this->matches(*this->last_check_))
+      if (this->matches(last_check))
         this->trigger();
     }
   }
diff --git a/esphome/components/tlc5971/tlc5971.cpp b/esphome/components/tlc5971/tlc5971.cpp
index be17780f8c..8128dd9046 100644
--- a/esphome/components/tlc5971/tlc5971.cpp
+++ b/esphome/components/tlc5971/tlc5971.cpp
@@ -68,13 +68,8 @@ void TLC5971::transfer_(uint8_t send) {
   uint8_t startbit = 0x80;
 
   bool towrite, lastmosi = !(send & startbit);
-  uint8_t bitdelay_us = (1000000 / 1000000) / 2;
 
   for (uint8_t b = startbit; b != 0; b = b >> 1) {
-    if (bitdelay_us) {
-      delayMicroseconds(bitdelay_us);
-    }
-
     towrite = send & b;
     if ((lastmosi != towrite)) {
       this->data_pin_->digital_write(towrite);
@@ -82,11 +77,6 @@ void TLC5971::transfer_(uint8_t send) {
     }
 
     this->clock_pin_->digital_write(true);
-
-    if (bitdelay_us) {
-      delayMicroseconds(bitdelay_us);
-    }
-
     this->clock_pin_->digital_write(false);
   }
 }
diff --git a/esphome/components/tormatic/tormatic_cover.cpp b/esphome/components/tormatic/tormatic_cover.cpp
index a58228a219..cca7b2bba0 100644
--- a/esphome/components/tormatic/tormatic_cover.cpp
+++ b/esphome/components/tormatic/tormatic_cover.cpp
@@ -282,12 +282,13 @@ optional<GateStatus> Tormatic::read_gate_status_() {
     }
   }
 
+  auto hdr = this->pending_hdr_.value();
+
   // Wait for all payload bytes to arrive before processing.
-  if (this->available() < this->pending_hdr_->payload_size()) {
+  if (this->available() < hdr.payload_size()) {
     return {};
   }
 
-  auto hdr = *this->pending_hdr_;
   this->pending_hdr_.reset();
 
   switch (hdr.type) {
diff --git a/esphome/components/toshiba/toshiba.cpp b/esphome/components/toshiba/toshiba.cpp
index 53114cc50f..a23b4c7cc3 100644
--- a/esphome/components/toshiba/toshiba.cpp
+++ b/esphome/components/toshiba/toshiba.cpp
@@ -275,7 +275,7 @@ static Ras2819tSecondPacketCodes get_ras_2819t_second_packet_codes(climate::Clim
  */
 static uint8_t get_ras_2819t_temp_code(float temperature) {
   int temp_index = static_cast<int>(temperature) - 18;
-  if (temp_index < 0 || temp_index >= static_cast<int>(sizeof(RAS_2819T_TEMP_CODES))) {
+  if (temp_index < 0 || static_cast<size_t>(temp_index) >= sizeof(RAS_2819T_TEMP_CODES)) {
     ESP_LOGW(TAG, "Temperature %.1f°C out of range [18-30°C], defaulting to 24°C", temperature);
     return 0x40;  // Default to 24°C
   }
diff --git a/esphome/components/usb_host/__init__.py b/esphome/components/usb_host/__init__.py
index 338bd8d572..8e591bd80c 100644
--- a/esphome/components/usb_host/__init__.py
+++ b/esphome/components/usb_host/__init__.py
@@ -10,6 +10,7 @@ from esphome.components.esp32 import (
 )
 import esphome.config_validation as cv
 from esphome.const import CONF_DEVICES, CONF_ID
+from esphome.core import CORE
 from esphome.cpp_types import Component
 from esphome.types import ConfigType
 
@@ -19,14 +20,15 @@ DEPENDENCIES = ["esp32"]
 usb_host_ns = cg.esphome_ns.namespace("usb_host")
 USBHost = usb_host_ns.class_("USBHost", Component)
 USBClient = usb_host_ns.class_("USBClient", Component)
-
+DOMAIN = "usb_host"
 CONF_VID = "vid"
 CONF_PID = "pid"
 CONF_ENABLE_HUBS = "enable_hubs"
 CONF_MAX_TRANSFER_REQUESTS = "max_transfer_requests"
+CONF_MAX_PACKET_SIZE = "max_packet_size"
 
 
-def usb_device_schema(cls=USBClient, vid: int = None, pid: [int] = None) -> cv.Schema:
+def usb_device_schema(cls=USBClient, vid: int = None, pid: int = None) -> cv.Schema:
     schema = cv.COMPONENT_SCHEMA.extend(
         {
             cv.GenerateID(): cv.declare_id(cls),
@@ -43,6 +45,17 @@ def usb_device_schema(cls=USBClient, vid: int = None, pid: [int] = None) -> cv.S
     return schema
 
 
+def _set_max_packet_size(config: dict) -> dict:
+    CORE.data.setdefault(DOMAIN, {})[CONF_MAX_PACKET_SIZE] = config[
+        CONF_MAX_PACKET_SIZE
+    ]
+    return config
+
+
+def get_max_packet_size() -> int:
+    return CORE.data.get(DOMAIN, {}).get(CONF_MAX_PACKET_SIZE, 64)
+
+
 CONFIG_SCHEMA = cv.All(
     cv.COMPONENT_SCHEMA.extend(
         {
@@ -51,10 +64,14 @@ CONFIG_SCHEMA = cv.All(
             cv.Optional(CONF_MAX_TRANSFER_REQUESTS, default=16): cv.int_range(
                 min=1, max=32
             ),
+            cv.Optional(CONF_MAX_PACKET_SIZE, default=64): cv.one_of(
+                64, 128, 256, 512, 1024, int=True
+            ),
             cv.Optional(CONF_DEVICES): cv.ensure_list(usb_device_schema()),
         }
     ),
     only_on_variant(supported=[VARIANT_ESP32P4, VARIANT_ESP32S2, VARIANT_ESP32S3]),
+    _set_max_packet_size,
 )
 
 
@@ -72,8 +89,8 @@ async def to_code(config: ConfigType) -> None:
     if config.get(CONF_ENABLE_HUBS):
         add_idf_sdkconfig_option("CONFIG_USB_HOST_HUBS_SUPPORTED", True)
 
-    max_requests = config[CONF_MAX_TRANSFER_REQUESTS]
-    cg.add_define("USB_HOST_MAX_REQUESTS", max_requests)
+    cg.add_define("USB_HOST_MAX_REQUESTS", config[CONF_MAX_TRANSFER_REQUESTS])
+    cg.add_define("USB_HOST_MAX_PACKET_SIZE", config[CONF_MAX_PACKET_SIZE])
 
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
diff --git a/esphome/components/usb_host/usb_host.h b/esphome/components/usb_host/usb_host.h
index dcb76a3a3b..480fd86750 100644
--- a/esphome/components/usb_host/usb_host.h
+++ b/esphome/components/usb_host/usb_host.h
@@ -66,6 +66,8 @@ static_assert(MAX_REQUESTS >= 1 && MAX_REQUESTS <= 32, "MAX_REQUESTS must be bet
 using trq_bitmask_t = std::conditional<(MAX_REQUESTS <= 16), uint16_t, uint32_t>::type;
 static constexpr trq_bitmask_t ALL_REQUESTS_IN_USE = MAX_REQUESTS == 32 ? ~0 : (1 << MAX_REQUESTS) - 1;
 
+static constexpr size_t USB_MAX_PACKET_SIZE =
+    USB_HOST_MAX_PACKET_SIZE;                        // Max USB packet size (64 for FS, 512 for P4 HS)
 static constexpr size_t USB_EVENT_QUEUE_SIZE = 32;   // Size of event queue between USB task and main loop
 static constexpr size_t USB_TASK_STACK_SIZE = 4096;  // Stack size for USB task (same as ESP-IDF USB examples)
 static constexpr UBaseType_t USB_TASK_PRIORITY = 5;  // Higher priority than main loop (tskIDLE_PRIORITY + 5)
diff --git a/esphome/components/usb_host/usb_host_client.cpp b/esphome/components/usb_host/usb_host_client.cpp
index c34c7ef67d..4ee8e2ac5e 100644
--- a/esphome/components/usb_host/usb_host_client.cpp
+++ b/esphome/components/usb_host/usb_host_client.cpp
@@ -217,7 +217,7 @@ void USBClient::setup() {
   // Pre-allocate USB transfer buffers for all slots at startup
   // This avoids any dynamic allocation during runtime
   for (auto &request : this->requests_) {
-    usb_host_transfer_alloc(64, 0, &request.transfer);
+    usb_host_transfer_alloc(USB_MAX_PACKET_SIZE, 0, &request.transfer);
     request.client = this;  // Set once, never changes
   }
 
diff --git a/esphome/components/usb_uart/__init__.py b/esphome/components/usb_uart/__init__.py
index d542788fb9..1cf78fdbd5 100644
--- a/esphome/components/usb_uart/__init__.py
+++ b/esphome/components/usb_uart/__init__.py
@@ -1,7 +1,11 @@
 import esphome.codegen as cg
 from esphome.components.const import CONF_DATA_BITS, CONF_PARITY, CONF_STOP_BITS
 from esphome.components.uart import CONF_DEBUG_PREFIX, CONF_FLUSH_TIMEOUT, UARTComponent
-from esphome.components.usb_host import register_usb_client, usb_device_schema
+from esphome.components.usb_host import (
+    get_max_packet_size,
+    register_usb_client,
+    usb_device_schema,
+)
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_BAUD_RATE,
@@ -118,14 +122,14 @@ CONFIG_SCHEMA = cv.ensure_list(
 async def to_code(config):
     # The output chunk pool/queue are compile-time-sized templates shared by all
     # USBUartChannel instances, so use the largest buffer_size across every channel
-    # of every device.  Each chunk is 64 bytes (USB FS MPS); add one extra slot
-    # because LockFreeQueue<T,N> is a ring buffer that wastes one entry.
+    # of every device. Add one extra slot because LockFreeQueue<T,N> is a ring
+    # buffer that wastes one entry.
     max_buffer_size = max(
         channel[CONF_BUFFER_SIZE]
         for device in config
         for channel in device[CONF_CHANNELS]
     )
-    output_chunk_count = max_buffer_size // 64 + 1
+    output_chunk_count = max(max_buffer_size // get_max_packet_size(), 2) + 1
     cg.add_define("USB_UART_OUTPUT_CHUNK_COUNT", output_chunk_count)
 
     for device in config:
diff --git a/esphome/components/usb_uart/usb_uart.cpp b/esphome/components/usb_uart/usb_uart.cpp
index 30ec61fdc4..e3bf5e40bc 100644
--- a/esphome/components/usb_uart/usb_uart.cpp
+++ b/esphome/components/usb_uart/usb_uart.cpp
@@ -157,7 +157,7 @@ void USBUartChannel::write_array(const uint8_t *data, size_t len) {
       ESP_LOGE(TAG, "Output pool full - lost %zu bytes", len);
       break;
     }
-    size_t chunk_len = std::min(len, UsbOutputChunk::MAX_CHUNK_SIZE);
+    uint16_t chunk_len = std::min(len, UsbOutputChunk::MAX_CHUNK_SIZE);
     memcpy(chunk->data, data, chunk_len);
     chunk->length = static_cast<uint8_t>(chunk_len);
     // Push always succeeds: pool is sized to queue capacity (SIZE-1), so if
@@ -222,7 +222,7 @@ void USBUartComponent::loop() {
 
 #ifdef USE_UART_DEBUGGER
     if (channel->debug_) {
-      char buf[4 + format_hex_pretty_size(UsbDataChunk::MAX_CHUNK_SIZE)];  // "<<< " + hex
+      char buf[4 + format_hex_pretty_size(usb_host::USB_MAX_PACKET_SIZE)];  // "<<< " + hex
       memcpy(buf, "<<< ", 4);
       format_hex_pretty_to(buf + 4, sizeof(buf) - 4, chunk->data, chunk->length, ',');
       ESP_LOGD(TAG, "%s%s", channel->debug_prefix_.c_str(), buf);
@@ -377,7 +377,7 @@ void USBUartComponent::start_output(USBUartChannel *channel) {
     this->start_output(channel);
   };
 
-  const uint8_t len = chunk->length;
+  const auto len = chunk->length;
   if (!this->transfer_out(ep->bEndpointAddress, callback, chunk->data, len)) {
     // Transfer submission failed — return chunk and release flag so callers can retry.
     channel->output_pool_.release(chunk);
@@ -394,10 +394,10 @@ void USBUartComponent::start_output(USBUartChannel *channel) {
 static void fix_mps(const usb_ep_desc_t *ep) {
   if (ep != nullptr) {
     auto *ep_mutable = const_cast<usb_ep_desc_t *>(ep);
-    if (ep->wMaxPacketSize > 64) {
-      ESP_LOGW(TAG, "Corrected MPS of EP 0x%02X from %u to 64", static_cast<uint8_t>(ep->bEndpointAddress & 0xFF),
-               ep->wMaxPacketSize);
-      ep_mutable->wMaxPacketSize = 64;
+    if (ep->wMaxPacketSize > usb_host::USB_MAX_PACKET_SIZE) {
+      ESP_LOGW(TAG, "Corrected MPS of EP 0x%02X from %u to %u", static_cast<uint8_t>(ep->bEndpointAddress & 0xFF),
+               ep->wMaxPacketSize, usb_host::USB_MAX_PACKET_SIZE);
+      ep_mutable->wMaxPacketSize = usb_host::USB_MAX_PACKET_SIZE;
     }
   }
 }
diff --git a/esphome/components/usb_uart/usb_uart.h b/esphome/components/usb_uart/usb_uart.h
index f9648b795b..e88c41c0cb 100644
--- a/esphome/components/usb_uart/usb_uart.h
+++ b/esphome/components/usb_uart/usb_uart.h
@@ -106,20 +106,19 @@ class RingBuffer {
 
 // Structure for queuing received USB data chunks
 struct UsbDataChunk {
-  static constexpr size_t MAX_CHUNK_SIZE = 64;  // USB packet size
-  uint8_t data[MAX_CHUNK_SIZE];
-  uint8_t length;  // Max 64 bytes, so uint8_t is sufficient
+  uint8_t data[usb_host::USB_MAX_PACKET_SIZE];
+  uint16_t length;
   USBUartChannel *channel;
 
   // Required for EventPool - no cleanup needed for POD types
   void release() {}
 };
 
-// Structure for queuing outgoing USB data chunks (one per USB FS packet)
+// Structure for queuing outgoing USB data chunks (one per USB packet)
 struct UsbOutputChunk {
-  static constexpr size_t MAX_CHUNK_SIZE = 64;  // USB FS MPS
+  static constexpr size_t MAX_CHUNK_SIZE = usb_host::USB_MAX_PACKET_SIZE;
   uint8_t data[MAX_CHUNK_SIZE];
-  uint8_t length;
+  uint16_t length;
 
   // Required for EventPool - no cleanup needed for POD types
   void release() {}
diff --git a/esphome/components/valve/__init__.py b/esphome/components/valve/__init__.py
index a6808c9da7..d82a9fdec2 100644
--- a/esphome/components/valve/__init__.py
+++ b/esphome/components/valve/__init__.py
@@ -21,14 +21,14 @@ from esphome.const import (
     DEVICE_CLASS_GAS,
     DEVICE_CLASS_WATER,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, Lambda, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
     queue_entity_register,
     setup_device_class,
     setup_entity,
 )
-from esphome.cpp_generator import MockObjClass
+from esphome.cpp_generator import LambdaExpression, MockObjClass
 
 IS_PLATFORM_COMPONENT = True
 
@@ -43,6 +43,7 @@ DEVICE_CLASSES = [
 valve_ns = cg.esphome_ns.namespace("valve")
 
 Valve = valve_ns.class_("Valve", cg.EntityBase)
+ValveCall = valve_ns.class_("ValveCall")
 
 VALVE_OPEN = valve_ns.VALVE_OPEN
 VALVE_CLOSED = valve_ns.VALVE_CLOSED
@@ -228,17 +229,48 @@ VALVE_CONTROL_ACTION_SCHEMA = cv.Schema(
 )
 async def valve_control_to_code(config, action_id, template_arg, args):
     paren = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, paren)
-    if stop_config := config.get(CONF_STOP):
-        template_ = await cg.templatable(stop_config, args, cg.bool_)
-        cg.add(var.set_stop(template_))
-    if state_config := config.get(CONF_STATE):
-        template_ = await cg.templatable(state_config, args, cg.float_)
-        cg.add(var.set_position(template_))
-    if (position_config := config.get(CONF_POSITION)) is not None:
-        template_ = await cg.templatable(position_config, args, cg.float_)
-        cg.add(var.set_position(template_))
-    return var
+
+    # All configured fields are folded into a single stateless lambda whose
+    # constants live in flash; the action stores only a function pointer.
+    # CONF_STATE and CONF_POSITION are cv.Exclusive in the schema, so at most
+    # one is present and both dispatch to set_position.
+    FIELDS = (
+        (CONF_STOP, "set_stop", cg.bool_),
+        (CONF_STATE, "set_position", cg.float_),
+        (CONF_POSITION, "set_position", cg.float_),
+    )
+
+    # Normalize trigger args to `const std::remove_cvref_t<T> &` so the
+    # apply lambda and any inner field lambdas (generated below via
+    # `process_lambda`) share one parameter spelling that's well-formed for
+    # any T (value, ref, or const-ref). Matches ControlAction::ApplyFn.
+    normalized_args = [
+        (cg.RawExpression(f"const std::remove_cvref_t<{cg.safe_exp(t)}> &"), n)
+        for t, n in args
+    ]
+
+    fwd_args = ", ".join(name for _, name in args)
+    body_lines: list[str] = []
+    for conf_key, setter, type_ in FIELDS:
+        if (value := config.get(conf_key)) is None:
+            continue
+        if isinstance(value, Lambda):
+            inner = await cg.process_lambda(value, normalized_args, return_type=type_)
+            body_lines.append(f"call.{setter}(({inner})({fwd_args}));")
+        else:
+            body_lines.append(f"call.{setter}({cg.safe_exp(value)});")
+
+    apply_args = [
+        (ValveCall.operator("ref"), "call"),
+        *normalized_args,
+    ]
+    apply_lambda = LambdaExpression(
+        ["\n".join(body_lines)],
+        apply_args,
+        capture="",
+        return_type=cg.void,
+    )
+    return cg.new_Pvariable(action_id, template_arg, paren, apply_lambda)
 
 
 @coroutine_with_priority(CoroPriority.CORE)
diff --git a/esphome/components/valve/automation.h b/esphome/components/valve/automation.h
index a064f375f7..27c0e329f0 100644
--- a/esphome/components/valve/automation.h
+++ b/esphome/components/valve/automation.h
@@ -47,24 +47,32 @@ template<typename... Ts> class ToggleAction : public Action<Ts...> {
   Valve *valve_;
 };
 
+// All configured fields are baked into a single stateless lambda whose
+// constants live in flash. The action only stores one function pointer
+// plus one parent pointer, regardless of how many fields the user set.
+// Trigger args are forwarded to the apply function so user lambdas
+// (e.g. `position: !lambda "return x;"`) keep working.
+//
+// Trigger args are normalized to `const std::remove_cvref_t<Ts> &...` so
+// the codegen can emit a matching parameter list for both the apply lambda
+// and any inner field lambdas without producing invalid C++ source text
+// (e.g. `const T & &` if Ts already carries a reference, or `const const
+// T &` if Ts already carries a const). This keeps trigger args no-copy
+// regardless of whether the trigger supplies `T`, `T &`, or `const T &`.
 template<typename... Ts> class ControlAction : public Action<Ts...> {
  public:
-  explicit ControlAction(Valve *valve) : valve_(valve) {}
-
-  TEMPLATABLE_VALUE(bool, stop)
-  TEMPLATABLE_VALUE(float, position)
+  using ApplyFn = void (*)(ValveCall &, const std::remove_cvref_t<Ts> &...);
+  ControlAction(Valve *valve, ApplyFn apply) : valve_(valve), apply_(apply) {}
 
   void play(const Ts &...x) override {
     auto call = this->valve_->make_call();
-    if (this->stop_.has_value())
-      call.set_stop(this->stop_.value(x...));
-    if (this->position_.has_value())
-      call.set_position(this->position_.value(x...));
+    this->apply_(call, x...);
     call.perform();
   }
 
  protected:
   Valve *valve_;
+  ApplyFn apply_;
 };
 
 template<typename... Ts> class ValveIsOpenCondition : public Condition<Ts...> {
diff --git a/esphome/components/watchdog/watchdog.cpp b/esphome/components/watchdog/watchdog.cpp
index 2ce46756e4..edf113b0b4 100644
--- a/esphome/components/watchdog/watchdog.cpp
+++ b/esphome/components/watchdog/watchdog.cpp
@@ -6,7 +6,6 @@
 #include <cinttypes>
 #include <cstdint>
 #ifdef USE_ESP32
-#include <soc/soc_caps.h>
 #include "esp_idf_version.h"
 #include "esp_task_wdt.h"
 #endif
@@ -40,9 +39,18 @@ void WatchdogManager::set_timeout_(uint32_t timeout_ms) {
 #ifdef USE_ESP32
   esp_task_wdt_config_t wdt_config = {
       .timeout_ms = timeout_ms,
-      .idle_core_mask = (1 << SOC_CPU_CORES_NUM) - 1,
-      .trigger_panic = true,
+      .idle_core_mask = 0,
+      .trigger_panic = false,
   };
+#if CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0
+  wdt_config.idle_core_mask |= (1U << 0U);
+#endif
+#if CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1
+  wdt_config.idle_core_mask |= (1U << 1U);
+#endif
+#if CONFIG_ESP_TASK_WDT_PANIC
+  wdt_config.trigger_panic = true;
+#endif
   esp_task_wdt_reconfigure(&wdt_config);
 #endif  // USE_ESP32
 
diff --git a/esphome/components/wifi/__init__.py b/esphome/components/wifi/__init__.py
index bc4e177219..69544f3636 100644
--- a/esphome/components/wifi/__init__.py
+++ b/esphome/components/wifi/__init__.py
@@ -73,6 +73,7 @@ NO_WIFI_VARIANTS = [const.VARIANT_ESP32H2, const.VARIANT_ESP32P4]
 CONF_SAVE = "save"
 CONF_BAND_MODE = "band_mode"
 CONF_MIN_AUTH_MODE = "min_auth_mode"
+CONF_PHY_MODE = "phy_mode"
 CONF_POST_CONNECT_ROAMING = "post_connect_roaming"
 
 # Maximum number of WiFi networks that can be configured
@@ -112,6 +113,14 @@ WIFI_MIN_AUTH_MODES = {
     "WPA3": WifiMinAuthMode.WIFI_MIN_AUTH_MODE_WPA3,
 }
 VALIDATE_WIFI_MIN_AUTH_MODE = cv.enum(WIFI_MIN_AUTH_MODES, upper=True)
+
+WiFi8266PhyMode = wifi_ns.enum("WiFi8266PhyMode")
+WIFI_8266_PHY_MODES = {
+    "AUTO": WiFi8266PhyMode.WIFI_8266_PHY_MODE_AUTO,
+    "11B": WiFi8266PhyMode.WIFI_8266_PHY_MODE_11B,
+    "11G": WiFi8266PhyMode.WIFI_8266_PHY_MODE_11G,
+    "11N": WiFi8266PhyMode.WIFI_8266_PHY_MODE_11N,
+}
 WiFiConnectedCondition = wifi_ns.class_("WiFiConnectedCondition", Condition)
 WiFiEnabledCondition = wifi_ns.class_("WiFiEnabledCondition", Condition)
 WiFiAPActiveCondition = wifi_ns.class_("WiFiAPActiveCondition", Condition)
@@ -406,6 +415,10 @@ CONFIG_SCHEMA = cv.All(
                 cv.only_on_esp32,
                 only_on_variant(supported=[const.VARIANT_ESP32C5]),
             ),
+            cv.Optional(CONF_PHY_MODE): cv.All(
+                cv.enum(WIFI_8266_PHY_MODES, upper=True),
+                cv.only_on_esp8266,
+            ),
             cv.Optional(CONF_PASSIVE_SCAN, default=False): cv.boolean,
             cv.Optional(CONF_ENABLE_ON_BOOT, default=True): cv.boolean,
             cv.Optional(CONF_POST_CONNECT_ROAMING, default=True): cv.boolean,
@@ -569,6 +582,9 @@ async def to_code(config):
 
     if CORE.is_esp8266:
         cg.add_library("ESP8266WiFi", None)
+        if CONF_PHY_MODE in config:
+            cg.add_define("USE_WIFI_PHY_MODE")
+            cg.add(var.set_phy_mode(config[CONF_PHY_MODE]))
     elif CORE.is_rp2040:
         cg.add_library("WiFi", None)
 
diff --git a/esphome/components/wifi/wifi_component.cpp b/esphome/components/wifi/wifi_component.cpp
index f7c70b1147..edfb93bba2 100644
--- a/esphome/components/wifi/wifi_component.cpp
+++ b/esphome/components/wifi/wifi_component.cpp
@@ -309,6 +309,18 @@ bool CompactString::operator==(const StringRef &other) const {
 /// └──────────────────────────────────────────────────────────────────────┘
 
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_INFO
+#ifdef USE_WIFI_PHY_MODE
+// Use if-chain instead of switch to avoid jump table in RODATA (wastes RAM on ESP8266)
+static const LogString *phy_mode_to_log_string(WiFi8266PhyMode mode) {
+  if (mode == WIFI_8266_PHY_MODE_11B)
+    return LOG_STR("11B");
+  if (mode == WIFI_8266_PHY_MODE_11G)
+    return LOG_STR("11G");
+  if (mode == WIFI_8266_PHY_MODE_11N)
+    return LOG_STR("11N");
+  return LOG_STR("Auto");
+}
+#endif
 // Use if-chain instead of switch to avoid jump table in RODATA (wastes RAM on ESP8266)
 static const LogString *retry_phase_to_log_string(WiFiRetryPhase phase) {
   if (phase == WiFiRetryPhase::INITIAL_CONNECT)
@@ -1099,9 +1111,9 @@ void WiFiComponent::start_connecting(const WiFiAP &ap) {
   }
 
 #ifdef USE_WIFI_WPA2_EAP
-  auto eap_opt = ap.get_eap();
+  const auto &eap_opt = ap.get_eap();
   if (eap_opt.has_value()) {
-    EAPAuth eap_config = *eap_opt;
+    const EAPAuth &eap_config = *eap_opt;
     // clang-format off
     ESP_LOGV(
         TAG,
@@ -1535,6 +1547,9 @@ void WiFiComponent::dump_config() {
       break;
   }
   ESP_LOGCONFIG(TAG, "  Band Mode: %s", band_mode_s);
+#endif
+#ifdef USE_WIFI_PHY_MODE
+  ESP_LOGCONFIG(TAG, "  PHY Mode: %s", LOG_STR_ARG(phy_mode_to_log_string(this->phy_mode_)));
 #endif
   if (this->is_connected()) {
     this->print_connect_params_();
diff --git a/esphome/components/wifi/wifi_component.h b/esphome/components/wifi/wifi_component.h
index 53fb0728fb..0437267a1f 100644
--- a/esphome/components/wifi/wifi_component.h
+++ b/esphome/components/wifi/wifi_component.h
@@ -345,6 +345,17 @@ enum WifiMinAuthMode : uint8_t {
   WIFI_MIN_AUTH_MODE_WPA3,
 };
 
+#ifdef USE_WIFI_PHY_MODE
+// Values 1-3 match ESP8266 SDK phy_mode_t (PHY_MODE_11B=1, PHY_MODE_11G=2, PHY_MODE_11N=3).
+// AUTO leaves the SDK at its default (no wifi_set_phy_mode() call).
+enum WiFi8266PhyMode : uint8_t {
+  WIFI_8266_PHY_MODE_AUTO = 0,
+  WIFI_8266_PHY_MODE_11B = 1,
+  WIFI_8266_PHY_MODE_11G = 2,
+  WIFI_8266_PHY_MODE_11N = 3,
+};
+#endif
+
 #ifdef USE_ESP32
 struct IDFWiFiEvent;
 #endif
@@ -455,6 +466,9 @@ class WiFiComponent final : public Component {
 #if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
   void set_band_mode(wifi_band_mode_t band_mode) { this->band_mode_ = band_mode; }
 #endif
+#ifdef USE_WIFI_PHY_MODE
+  void set_phy_mode(WiFi8266PhyMode phy_mode) { this->phy_mode_ = phy_mode; }
+#endif
 
   void set_passive_scan(bool passive);
 
@@ -672,6 +686,9 @@ class WiFiComponent final : public Component {
   bool wifi_apply_power_save_();
 #if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
   bool wifi_apply_band_mode_();
+#endif
+#ifdef USE_WIFI_PHY_MODE
+  bool wifi_apply_phy_mode_();
 #endif
   bool wifi_sta_ip_config_(const optional<ManualIP> &manual_ip);
   bool wifi_apply_hostname_();
@@ -810,6 +827,9 @@ class WiFiComponent final : public Component {
   WiFiPowerSaveMode power_save_{WIFI_POWER_SAVE_NONE};
 #if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
   wifi_band_mode_t band_mode_{WIFI_BAND_MODE_AUTO};
+#endif
+#ifdef USE_WIFI_PHY_MODE
+  WiFi8266PhyMode phy_mode_{WIFI_8266_PHY_MODE_AUTO};
 #endif
   WifiMinAuthMode min_auth_mode_{WIFI_MIN_AUTH_MODE_WPA2};
   WiFiRetryPhase retry_phase_{WiFiRetryPhase::INITIAL_CONNECT};
diff --git a/esphome/components/wifi/wifi_component_esp8266.cpp b/esphome/components/wifi/wifi_component_esp8266.cpp
index bf3a0d2949..717d542fbe 100644
--- a/esphome/components/wifi/wifi_component_esp8266.cpp
+++ b/esphome/components/wifi/wifi_component_esp8266.cpp
@@ -313,10 +313,10 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
 
   // setup enterprise authentication if required
 #ifdef USE_WIFI_WPA2_EAP
-  auto eap_opt = ap.get_eap();
+  const auto &eap_opt = ap.get_eap();
   if (eap_opt.has_value()) {
     // note: all certificates and keys have to be null terminated. Lengths are appended by +1 to include \0.
-    EAPAuth eap = *eap_opt;
+    const EAPAuth &eap = *eap_opt;
     ret = wifi_station_set_enterprise_identity((uint8_t *) eap.identity.c_str(), eap.identity.length());
     if (ret) {
       ESP_LOGV(TAG, "esp_wifi_sta_wpa2_ent_set_identity failed: %d", ret);
@@ -621,10 +621,25 @@ bool WiFiComponent::wifi_sta_pre_setup_() {
     ESP_LOGV(TAG, "Disabling Auto-Connect failed");
   }
 
+#ifdef USE_WIFI_PHY_MODE
+  if (!this->wifi_apply_phy_mode_()) {
+    ESP_LOGV(TAG, "Setting PHY Mode failed");
+  }
+#endif
+
   delay(10);
   return true;
 }
 
+#ifdef USE_WIFI_PHY_MODE
+bool WiFiComponent::wifi_apply_phy_mode_() {
+  if (this->phy_mode_ == WIFI_8266_PHY_MODE_AUTO)
+    return true;
+  // Values of WiFi8266PhyMode are aligned with the SDK's phy_mode_t enum.
+  return wifi_set_phy_mode(static_cast<phy_mode_t>(this->phy_mode_));
+}
+#endif
+
 void WiFiComponent::wifi_pre_setup_() {
   wifi_set_event_handler_cb(&WiFiComponent::wifi_event_callback);
 
diff --git a/esphome/components/wifi/wifi_component_esp_idf.cpp b/esphome/components/wifi/wifi_component_esp_idf.cpp
index 29d135ce90..4f39a3a4b1 100644
--- a/esphome/components/wifi/wifi_component_esp_idf.cpp
+++ b/esphome/components/wifi/wifi_component_esp_idf.cpp
@@ -179,7 +179,10 @@ void WiFiComponent::wifi_pre_setup_() {
 #endif  // USE_WIFI_AP
 
   wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
-  // cfg.nvs_enable = false;
+  if (global_preferences->nvs_handle == 0) {
+    ESP_LOGW(TAG, "starting wifi without nvs");
+    cfg.nvs_enable = false;
+  }
   err = esp_wifi_init(&cfg);
   if (err != ERR_OK) {
     ESP_LOGE(TAG, "esp_wifi_init failed: %s", esp_err_to_name(err));
@@ -404,10 +407,10 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
 
   // setup enterprise authentication if required
 #ifdef USE_WIFI_WPA2_EAP
-  auto eap_opt = ap.get_eap();
+  const auto &eap_opt = ap.get_eap();
   if (eap_opt.has_value()) {
     // note: all certificates and keys have to be null terminated. Lengths are appended by +1 to include \0.
-    EAPAuth eap = *eap_opt;
+    const EAPAuth &eap = *eap_opt;
 #if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 1, 0)
     err = esp_eap_client_set_identity((uint8_t *) eap.identity.c_str(), eap.identity.length());
 #else
diff --git a/esphome/components/zephyr/core.cpp b/esphome/components/zephyr/core.cpp
index 93a9a1ae8e..d1bdaee02d 100644
--- a/esphome/components/zephyr/core.cpp
+++ b/esphome/components/zephyr/core.cpp
@@ -1,8 +1,6 @@
 #ifdef USE_ZEPHYR
 
 #include <zephyr/kernel.h>
-#include <zephyr/drivers/watchdog.h>
-#include <zephyr/sys/reboot.h>
 #include <zephyr/random/random.h>
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
@@ -10,55 +8,7 @@
 
 namespace esphome {
 
-#ifdef CONFIG_WATCHDOG
-static int wdt_channel_id = -1;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
-static const device *const WDT = DEVICE_DT_GET(DT_ALIAS(watchdog0));
-#endif
-
-void yield() { ::k_yield(); }
-uint32_t millis() { return static_cast<uint32_t>(millis_64()); }
-uint64_t millis_64() { return static_cast<uint64_t>(k_uptime_get()); }
-uint32_t micros() { return k_ticks_to_us_floor32(k_uptime_ticks()); }
-void delayMicroseconds(uint32_t us) { ::k_usleep(us); }
-void delay(uint32_t ms) { ::k_msleep(ms); }
-
-void arch_init() {
-#ifdef CONFIG_WATCHDOG
-  if (device_is_ready(WDT)) {
-    static wdt_timeout_cfg wdt_config{};
-    wdt_config.flags = WDT_FLAG_RESET_SOC;
-#ifdef USE_ZIGBEE
-    // zboss thread use a lot of cpu cycles during start
-    wdt_config.window.max = 10000;
-#else
-    wdt_config.window.max = 2000;
-#endif
-    wdt_channel_id = wdt_install_timeout(WDT, &wdt_config);
-    if (wdt_channel_id >= 0) {
-      uint8_t options = 0;
-#ifdef USE_DEBUG
-      options |= WDT_OPT_PAUSE_HALTED_BY_DBG;
-#endif
-#ifdef USE_DEEP_SLEEP
-      options |= WDT_OPT_PAUSE_IN_SLEEP;
-#endif
-      wdt_setup(WDT, options);
-    }
-  }
-#endif
-}
-
-void arch_feed_wdt() {
-#ifdef CONFIG_WATCHDOG
-  if (wdt_channel_id >= 0) {
-    wdt_feed(WDT, wdt_channel_id);
-  }
-#endif
-}
-
-void arch_restart() { sys_reboot(SYS_REBOOT_COLD); }
-uint32_t arch_get_cpu_cycle_count() { return k_cycle_get_32(); }
-uint32_t arch_get_cpu_freq_hz() { return sys_clock_hw_cycles_per_sec(); }
+// HAL functions live in hal.cpp.
 
 Mutex::Mutex() {
   auto *mutex = new k_mutex();
diff --git a/esphome/components/zephyr/hal.cpp b/esphome/components/zephyr/hal.cpp
new file mode 100644
index 0000000000..ad8ed5c95c
--- /dev/null
+++ b/esphome/components/zephyr/hal.cpp
@@ -0,0 +1,65 @@
+#ifdef USE_ZEPHYR
+
+#include "esphome/core/defines.h"
+#include "esphome/core/hal.h"
+
+#include <zephyr/drivers/watchdog.h>
+#include <zephyr/sys/reboot.h>
+
+// Empty zephyr namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// zephyr component's API.
+namespace esphome::zephyr {}  // namespace esphome::zephyr
+
+namespace esphome {
+
+#ifdef CONFIG_WATCHDOG
+static int wdt_channel_id = -1;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+static const device *const WDT = DEVICE_DT_GET(DT_ALIAS(watchdog0));
+#endif
+
+// yield(), delay(), micros(), millis(), millis_64(), delayMicroseconds(),
+// arch_get_cpu_cycle_count(), arch_get_cpu_freq_hz() inlined in
+// components/zephyr/hal.h.
+
+void arch_init() {
+#ifdef CONFIG_WATCHDOG
+  if (device_is_ready(WDT)) {
+    static wdt_timeout_cfg wdt_config{};
+    wdt_config.flags = WDT_FLAG_RESET_SOC;
+#ifdef USE_ZIGBEE
+    // zboss thread uses a lot of CPU cycles during startup
+    wdt_config.window.max = 10000;
+#else
+    wdt_config.window.max = 2000;
+#endif
+    wdt_channel_id = wdt_install_timeout(WDT, &wdt_config);
+    if (wdt_channel_id >= 0) {
+      uint8_t options = 0;
+#ifdef USE_DEBUG
+      options |= WDT_OPT_PAUSE_HALTED_BY_DBG;
+#endif
+#ifdef USE_DEEP_SLEEP
+      options |= WDT_OPT_PAUSE_IN_SLEEP;
+#endif
+      wdt_setup(WDT, options);
+    }
+  }
+#endif
+  // feed watchdog early. Otherwise OTA may rollback.
+  arch_feed_wdt();
+}
+
+void arch_feed_wdt() {
+#ifdef CONFIG_WATCHDOG
+  if (wdt_channel_id >= 0) {
+    wdt_feed(WDT, wdt_channel_id);
+  }
+#endif
+}
+
+void arch_restart() { sys_reboot(SYS_REBOOT_COLD); }
+
+}  // namespace esphome
+
+#endif  // USE_ZEPHYR
diff --git a/esphome/components/zephyr/hal.h b/esphome/components/zephyr/hal.h
new file mode 100644
index 0000000000..11994b68b7
--- /dev/null
+++ b/esphome/components/zephyr/hal.h
@@ -0,0 +1,36 @@
+#pragma once
+
+#ifdef USE_ZEPHYR
+
+#include <cstdint>
+
+#include <zephyr/kernel.h>
+
+#define IRAM_ATTR
+#define PROGMEM
+
+namespace esphome::zephyr {}
+
+namespace esphome {
+
+/// Returns true when executing inside an interrupt handler.
+/// Zephyr/nRF52: not currently consulted — wake path is platform-specific.
+__attribute__((always_inline)) inline bool in_isr_context() { return false; }
+
+__attribute__((always_inline)) inline void yield() { ::k_yield(); }
+__attribute__((always_inline)) inline void delay(uint32_t ms) { ::k_msleep(ms); }
+__attribute__((always_inline)) inline uint32_t micros() { return k_ticks_to_us_floor32(k_uptime_ticks()); }
+__attribute__((always_inline)) inline uint64_t millis_64() { return static_cast<uint64_t>(k_uptime_get()); }
+__attribute__((always_inline)) inline uint32_t millis() { return static_cast<uint32_t>(millis_64()); }
+
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { ::k_usleep(us); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() { return k_cycle_get_32(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_freq_hz() { return sys_clock_hw_cycles_per_sec(); }
+
+void arch_feed_wdt();
+void arch_init();
+
+}  // namespace esphome
+
+#endif  // USE_ZEPHYR
diff --git a/esphome/components/zigbee/zigbee_esp32.py b/esphome/components/zigbee/zigbee_esp32.py
index 1b98df6c0a..9081582c7b 100644
--- a/esphome/components/zigbee/zigbee_esp32.py
+++ b/esphome/components/zigbee/zigbee_esp32.py
@@ -9,6 +9,7 @@ from esphome.components.esp32 import (
     add_idf_component,
     add_idf_sdkconfig_option,
     add_partition,
+    idf_version,
     require_vfs_select,
 )
 import esphome.config_validation as cv
@@ -186,6 +187,10 @@ async def _zigbee_add_sdkconfigs(config: ConfigType) -> None:
     # The pre-built Zigbee library uses esp_log_default_level which requires
     # dynamic log level control to be enabled
     add_idf_sdkconfig_option("CONFIG_LOG_DYNAMIC_LEVEL_CONTROL", True)
+    # The pre-built Zigbee library is compiled against newlib which requires newlib
+    # reentrancy to be enabled with picolibc compatibility.
+    if idf_version() >= cv.Version(6, 0, 0):
+        add_idf_sdkconfig_option("CONFIG_LIBC_PICOLIBC_NEWLIB_COMPATIBILITY", True)
 
 
 async def attributes_to_code(
diff --git a/esphome/components/zigbee/zigbee_zephyr.cpp b/esphome/components/zigbee/zigbee_zephyr.cpp
index dfffd1c91f..26bef8fb17 100644
--- a/esphome/components/zigbee/zigbee_zephyr.cpp
+++ b/esphome/components/zigbee/zigbee_zephyr.cpp
@@ -4,9 +4,7 @@
 #include <zephyr/settings/settings.h>
 #include <zephyr/storage/flash_map.h>
 #include "esphome/core/hal.h"
-#ifdef USE_DEEP_SLEEP
-#include "esphome/components/deep_sleep/deep_sleep_component.h"
-#endif
+#include "esphome/core/wake.h"
 
 extern "C" {
 #include <zboss_api.h>
@@ -119,11 +117,7 @@ void ZigbeeComponent::zcl_device_cb(zb_bufid_t bufid) {
   /* Set default response value. */
   p_device_cb_param->status = RET_OK;
 
-#ifdef USE_DEEP_SLEEP
-  if (auto *ds = deep_sleep::global_deep_sleep.load()) {
-    ds->wakeup();
-  }
-#endif
+  esphome::wake_loop_threadsafe();
 
   // endpoints are enumerated from 1
   if (global_zigbee->callbacks_.size() >= endpoint) {
diff --git a/esphome/config.py b/esphome/config.py
index 6eb67af58b..79d0d2b02b 100644
--- a/esphome/config.py
+++ b/esphome/config.py
@@ -25,7 +25,10 @@ from esphome.const import (
     CONF_SUBSTITUTIONS,
 )
 from esphome.core import CORE, DocumentRange, EsphomeError
-import esphome.core.config as core_config
+
+# `esphome.core.config` is imported lazily at its two use sites below.
+# It pulls in `esphome.automation` and `esphome.config_validation`, which
+# dominate `esphome.__main__` startup cost when loaded eagerly here.
 import esphome.final_validate as fv
 from esphome.helpers import indent
 from esphome.loader import ComponentManifest, get_component, get_platform
@@ -968,6 +971,8 @@ class CoreFinalValidateStep(ConfigValidationStep):
         if result.errors:
             return
 
+        import esphome.core.config as core_config
+
         token = fv.full_config.set(result)
         with result.catch_error([CONF_ESPHOME]):
             if CONF_ESPHOME in result:
@@ -1073,6 +1078,8 @@ def validate_config(
         return result
 
     # 2. Load partial core config
+    import esphome.core.config as core_config
+
     result[CONF_ESPHOME] = config[CONF_ESPHOME]
     result.add_output_path([CONF_ESPHOME], CONF_ESPHOME)
     try:
diff --git a/esphome/core/__init__.py b/esphome/core/__init__.py
index 4fecebcd8d..94a48dd31b 100644
--- a/esphome/core/__init__.py
+++ b/esphome/core/__init__.py
@@ -779,6 +779,17 @@ class EsphomeCore:
             return self.relative_pioenvs_path(self.name, "firmware.uf2")
         return self.relative_pioenvs_path(self.name, "firmware.bin")
 
+    @property
+    def partition_table_bin(self) -> Path:
+        # Native ESP-IDF (--native-idf): the partition table image is emitted under
+        # build/partition_table/partition-table.bin alongside firmware.bin. PlatformIO writes the
+        # equivalent file as partitions.bin in the env-specific .pioenvs directory.
+        if self.data.get(KEY_NATIVE_IDF):
+            return self.relative_build_path(
+                "build", "partition_table", "partition-table.bin"
+            )
+        return self.relative_pioenvs_path(self.name, "partitions.bin")
+
     @property
     def target_platform(self):
         return self.data[KEY_CORE][KEY_TARGET_PLATFORM]
diff --git a/esphome/core/application.h b/esphome/core/application.h
index 185ee4163b..369c970d46 100644
--- a/esphome/core/application.h
+++ b/esphome/core/application.h
@@ -9,6 +9,10 @@
 #include <vector>
 #include "esphome/core/component.h"
 #include "esphome/core/defines.h"
+
+#if defined(USE_LWIP_FAST_SELECT) && defined(ESPHOME_THREAD_MULTI_ATOMICS)
+#include <atomic>  // for std::atomic_thread_fence in Application::loop()
+#endif
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
 #include "esphome/core/preferences.h"
@@ -229,11 +233,10 @@ class Application {
   /// loops and scheduler items still feed after every op, so any op exceeding
   /// this threshold triggers a real feed naturally.
   /// Safety margins vs. platform watchdog timeouts:
-  ///   - ESP32 task WDT (user-configurable):  ~5x  <-- auto-scaled below
-  ///   - ESP8266 soft WDT (~1.6 s):           ~5x  <-- floor case; any future change
-  ///                                                   must keep comfortable margin here
-  ///   - ESP8266 HW WDT (~6 s):               ~20x
-  ///   - BK72xx HW WDT (10 s):                ~5x  <-- platform override below
+  ///   - ESP32 task WDT (user-configurable):  ~5x   <-- auto-scaled below
+  ///   - ESP8266 soft WDT (~1.6 s):           ~16x  <-- 100 ms feed (see USE_ESP8266 below)
+  ///   - ESP8266 HW WDT (~6 s):               ~60x
+  ///   - BK72xx HW WDT (10 s):                ~5x   <-- platform override below
 #ifdef USE_BK72XX
   // BDK busy-waits 200us per WDT reload (sctrl_dpll_delay200us). LibreTiny
   // sets HW WDT to 10s; 2000ms keeps ~5x margin. See wdt_ctrl WCMD_RELOAD_PERIOD:
@@ -253,6 +256,15 @@ class Application {
   static_assert(CONFIG_ESP_TASK_WDT_TIMEOUT_S >= 5,
                 "CONFIG_ESP_TASK_WDT_TIMEOUT_S must be at least 5s for a safe WDT feed interval");
   static constexpr uint32_t WDT_FEED_INTERVAL_MS = (CONFIG_ESP_TASK_WDT_TIMEOUT_S * 1000U) / 5U;
+#elif defined(USE_ESP8266)
+  // ESP8266 needs a tighter feed cadence than the other targets: the soft WDT
+  // is ~1.6 s and the HW WDT ~6 s, but a single long iteration (mDNS reply,
+  // wifi scan, OTA verify, lwIP TCP retransmit storm) can push the loop past
+  // a few hundred ms without giving the SDK a chance to feed. 100 ms keeps a
+  // ~16x margin to the soft WDT and ~60x to the HW WDT while still avoiding
+  // the per-iteration arch_feed_wdt() cost (this is the rate limit; component
+  // loops and scheduler items still feed after every op).
+  static constexpr uint32_t WDT_FEED_INTERVAL_MS = 100;
 #else
   static constexpr uint32_t WDT_FEED_INTERVAL_MS = 300;
 #endif
@@ -370,6 +382,9 @@ class Application {
 #elif defined(USE_ESP8266)
   /// Wake from ISR (ESP8266). No task_woken arg — no FreeRTOS. Caller must be IRAM_ATTR.
   static void IRAM_ATTR ESPHOME_ALWAYS_INLINE wake_loop_isrsafe() { esphome::wake_loop_isrsafe(); }
+#elif defined(USE_ZEPHYR)
+  /// Wake from ISR (Zephyr). No task_woken arg — k_sem_give() handles ISR scheduling internally.
+  static void wake_loop_isrsafe() { esphome::wake_loop_isrsafe(); }
 #endif
 
   /// Wake from any context (ISR, thread, callback).
@@ -377,12 +392,16 @@ class Application {
 
  protected:
   friend Component;
+  friend class Scheduler;
 #ifdef USE_RUNTIME_STATS
   friend class runtime_stats::RuntimeStatsCollector;
 #endif
   friend void ::setup();
   friend void ::original_setup();
 
+  /// Freshen the cached loop component start time. Called by Scheduler before each dispatch.
+  void set_loop_component_start_time_(uint32_t now) { this->loop_component_start_time_ = now; }
+
   /// Walk all registered components looking for any whose component_state_
   /// has the given flag set. Used by Component::status_clear_*_slow_path_()
   /// (which is a friend) to decide whether to clear the corresponding bit on
@@ -573,6 +592,15 @@ inline ESPHOME_ALWAYS_INLINE Application::ComponentPhaseGuard::ComponentPhaseGua
 }
 
 inline void ESPHOME_ALWAYS_INLINE Application::loop() {
+#if defined(USE_LWIP_FAST_SELECT) && defined(ESPHOME_THREAD_MULTI_ATOMICS)
+  // Pairs with the TCP/IP thread's SYS_ARCH_UNPROTECT release on rcvevent so
+  // subsequent Socket::ready() checks in this iter observe the published state
+  // without a per-call memw. Wake is independent (xTaskNotifyGive/
+  // ulTaskNotifyTake), so non-losing. Skipped on MULTI_NO_ATOMICS (e.g.
+  // BK72xx) — that path keeps `volatile` in esphome_lwip_socket_has_data()
+  // instead.
+  std::atomic_thread_fence(std::memory_order_acquire);
+#endif
 #ifdef USE_RUNTIME_STATS
   // Capture the start of the active (non-sleeping) portion of this iteration.
   // Used to derive main-loop overhead = active time − Σ(component time) −
@@ -617,10 +645,12 @@ inline void ESPHOME_ALWAYS_INLINE Application::loop() {
   // flag preserves it. wake_request_take() exchange-clears the flag; wakes
   // that arrive during Phase B re-set it and run Phase B again on the next
   // iteration.
-  const bool high_frequency = HighFrequencyLoopRequester::is_high_frequency();
-  const uint32_t elapsed = now - this->last_loop_;
-  const bool woke = esphome::wake_request_take();
-  const bool do_component_phase = high_frequency || woke || (elapsed >= this->loop_interval_);
+  //
+  // wake_request_take() must always be called first since it does an
+  // atomic exchange to clear the flag, and we want to run the component phase
+  // if either the flag was set or the scheduler requested a high-frequency loop.
+  const bool do_component_phase = esphome::wake_request_take() || HighFrequencyLoopRequester::is_high_frequency() ||
+                                  (now - this->last_loop_ >= this->loop_interval_);
 
   if (do_component_phase) {
     ComponentPhaseGuard phase_guard{*this};
diff --git a/esphome/core/base_automation.h b/esphome/core/base_automation.h
index 17f937d10d..dcad7c9d2e 100644
--- a/esphome/core/base_automation.h
+++ b/esphome/core/base_automation.h
@@ -178,7 +178,7 @@ class ProjectUpdateTrigger : public Trigger<std::string>, public Component {
 };
 #endif
 
-template<typename... Ts> class DelayAction : public Action<Ts...>, public Component {
+template<typename... Ts> class DelayAction : public Action<Ts...> {
  public:
   explicit DelayAction() = default;
 
@@ -198,8 +198,8 @@ template<typename... Ts> class DelayAction : public Action<Ts...>, public Compon
     // to avoid overhead from capturing arguments by value
     if constexpr (sizeof...(Ts) == 0) {
       App.scheduler.set_timer_common_(
-          this, Scheduler::SchedulerItem::TIMEOUT, Scheduler::NameType::NUMERIC_ID_INTERNAL, nullptr,
-          static_cast<uint32_t>(InternalSchedulerID::DELAY_ACTION), this->delay_.value(),
+          /* component= */ nullptr, Scheduler::SchedulerItem::TIMEOUT, Scheduler::NameType::SELF_POINTER,
+          /* static_name= */ reinterpret_cast<const char *>(this), /* hash_or_id= */ 0, this->delay_.value(),
           [this]() { this->play_next_(); },
           /* is_retry= */ false, /* skip_cancel= */ this->num_running_ > 1);
     } else {
@@ -208,18 +208,18 @@ template<typename... Ts> class DelayAction : public Action<Ts...>, public Compon
       // `mutable` is required so captured copies of non-const reference args (e.g. std::string&)
       // are passed as non-const lvalues to play_next_(const Ts&...) where Ts may be `T&`
       auto f = [this, x...]() mutable { this->play_next_(x...); };
-      App.scheduler.set_timer_common_(this, Scheduler::SchedulerItem::TIMEOUT, Scheduler::NameType::NUMERIC_ID_INTERNAL,
-                                      nullptr, static_cast<uint32_t>(InternalSchedulerID::DELAY_ACTION),
-                                      this->delay_.value(x...), std::move(f),
-                                      /* is_retry= */ false, /* skip_cancel= */ this->num_running_ > 1);
+      App.scheduler.set_timer_common_(
+          /* component= */ nullptr, Scheduler::SchedulerItem::TIMEOUT, Scheduler::NameType::SELF_POINTER,
+          /* static_name= */ reinterpret_cast<const char *>(this), /* hash_or_id= */ 0, this->delay_.value(x...),
+          std::move(f),
+          /* is_retry= */ false, /* skip_cancel= */ this->num_running_ > 1);
     }
   }
-  float get_setup_priority() const override { return setup_priority::HARDWARE; }
 
   void play(const Ts &...x) override { /* ignore - see play_complex */
   }
 
-  void stop() override { this->cancel_timeout(InternalSchedulerID::DELAY_ACTION); }
+  void stop() override { App.scheduler.cancel_timeout(this); }
 };
 
 template<typename... Ts> class LambdaAction : public Action<Ts...> {
@@ -273,18 +273,32 @@ template<typename... Ts> class WhileLoopContinuation : public Action<Ts...> {
   WhileAction<Ts...> *parent_;
 };
 
+// Wraps a ContinuationAction when Enabled, empty otherwise.
+// Lets IfAction elide the else continuation when HasElse is false.
+template<bool Enabled, typename... Ts> struct OptionalContinuation {
+  ContinuationAction<Ts...> action;
+  explicit OptionalContinuation(Action<Ts...> *parent) : action(parent) {}
+};
+template<typename... Ts> struct OptionalContinuation<false, Ts...> {
+  explicit OptionalContinuation(Action<Ts...> * /*parent*/) {}
+};
+
 template<bool HasElse, typename... Ts> class IfAction : public Action<Ts...> {
  public:
   explicit IfAction(Condition<Ts...> *condition) : condition_(condition) {}
 
+  // Precondition: add_then/add_else must be called at most once per instance.
+  // Codegen always batches the full action list into a single call. Calling
+  // twice would re-append the same inline continuation pointer and form a
+  // self-loop in the next_ chain.
   void add_then(const std::initializer_list<Action<Ts...> *> &actions) {
     this->then_.add_actions(actions);
-    this->then_.add_action(new ContinuationAction<Ts...>(this));
+    this->then_.add_action(&this->then_continuation_);
   }
 
   void add_else(const std::initializer_list<Action<Ts...> *> &actions) requires(HasElse) {
     this->else_.add_actions(actions);
-    this->else_.add_action(new ContinuationAction<Ts...>(this));
+    this->else_.add_action(&this->else_continuation_.action);
   }
 
   void play_complex(const Ts &...x) override {
@@ -316,17 +330,20 @@ template<bool HasElse, typename... Ts> class IfAction : public Action<Ts...> {
  protected:
   Condition<Ts...> *condition_;
   ActionList<Ts...> then_;
+  ContinuationAction<Ts...> then_continuation_{this};
   struct NoElse {};
   [[no_unique_address]] std::conditional_t<HasElse, ActionList<Ts...>, NoElse> else_;
+  [[no_unique_address]] OptionalContinuation<HasElse, Ts...> else_continuation_{this};
 };
 
 template<typename... Ts> class WhileAction : public Action<Ts...> {
  public:
   WhileAction(Condition<Ts...> *condition) : condition_(condition) {}
 
+  // Precondition: must be called at most once per instance (see IfAction::add_then).
   void add_then(const std::initializer_list<Action<Ts...> *> &actions) {
     this->then_.add_actions(actions);
-    this->then_.add_action(new WhileLoopContinuation<Ts...>(this));
+    this->then_.add_action(&this->loop_continuation_);
   }
 
   friend class WhileLoopContinuation<Ts...>;
@@ -354,6 +371,7 @@ template<typename... Ts> class WhileAction : public Action<Ts...> {
  protected:
   Condition<Ts...> *condition_;
   ActionList<Ts...> then_;
+  WhileLoopContinuation<Ts...> loop_continuation_{this};
 };
 
 // Implementation of WhileLoopContinuation::play
@@ -386,9 +404,10 @@ template<typename... Ts> class RepeatAction : public Action<Ts...> {
  public:
   TEMPLATABLE_VALUE(uint32_t, count)
 
+  // Precondition: must be called at most once per instance (see IfAction::add_then).
   void add_then(const std::initializer_list<Action<uint32_t, Ts...> *> &actions) {
     this->then_.add_actions(actions);
-    this->then_.add_action(new RepeatLoopContinuation<Ts...>(this));
+    this->then_.add_action(&this->loop_continuation_);
   }
 
   friend class RepeatLoopContinuation<Ts...>;
@@ -409,6 +428,7 @@ template<typename... Ts> class RepeatAction : public Action<Ts...> {
 
  protected:
   ActionList<uint32_t, Ts...> then_;
+  RepeatLoopContinuation<Ts...> loop_continuation_{this};
 };
 
 // Implementation of RepeatLoopContinuation::play
diff --git a/esphome/core/color.h b/esphome/core/color.h
index 32d63b1856..442470623d 100644
--- a/esphome/core/color.h
+++ b/esphome/core/color.h
@@ -169,7 +169,7 @@ struct Color {
     uint8_t r = rand >> 16;
     uint8_t g = rand >> 8;
     uint8_t b = rand >> 0;
-    const uint16_t max_rgb = std::max(r, std::max(g, b));
+    const uint16_t max_rgb = std::max({r, g, b});
     return Color(uint8_t((uint16_t(r) * 255U / max_rgb)), uint8_t((uint16_t(g) * 255U / max_rgb)),
                  uint8_t((uint16_t(b) * 255U / max_rgb)), w);
   }
diff --git a/esphome/core/component.h b/esphome/core/component.h
index 6afcfda41d..5baf795ca6 100644
--- a/esphome/core/component.h
+++ b/esphome/core/component.h
@@ -65,7 +65,6 @@ inline constexpr uint32_t SCHEDULER_DONT_RUN = 4294967295UL;
 /// with component-level NUMERIC_ID values, even if the uint32_t values overlap.
 enum class InternalSchedulerID : uint32_t {
   POLLING_UPDATE = 0,  // PollingComponent interval
-  DELAY_ACTION = 1,    // DelayAction timeout
 };
 
 // Forward declaration
@@ -655,7 +654,15 @@ class WarnIfComponentBlockingGuard {
   // Inlined: the fast path is just millis() + subtract + compare
   inline uint32_t HOT finish() {
 #ifdef USE_RUNTIME_STATS
-    this->component_->runtime_stats_.record_time(micros() - this->started_us_);
+    uint32_t elapsed_us = micros() - this->started_us_;
+    // component_ is nullptr for self-keyed scheduler items (set_timeout/set_interval(self, ...))
+    if (this->component_ != nullptr) {
+      this->component_->runtime_stats_.record_time(elapsed_us);
+    } else {
+      // Still accumulate into the global counter so Application::loop() can subtract
+      // this time from before_loop_tasks_ wall time.
+      ComponentRuntimeStats::global_recorded_us += elapsed_us;
+    }
 #endif
     uint32_t curr_time = MillisInternal::get();
 #ifndef USE_BENCHMARK
diff --git a/esphome/core/config.py b/esphome/core/config.py
index 018e05f17b..b4e81ce49f 100644
--- a/esphome/core/config.py
+++ b/esphome/core/config.py
@@ -792,6 +792,29 @@ FILTER_SOURCE_FILES = filter_source_files_from_platform(
             PlatformFramework.RTL87XX_ARDUINO,
             PlatformFramework.LN882X_ARDUINO,
         },
+        # Per-platform wake implementations — wake.h dispatches to exactly one of
+        # these based on USE_*, so the others can be skipped at the source level
+        # too. Header files next to each .cpp are always copied (the dispatcher
+        # #include's them) but compile to empty TUs on the wrong platform anyway.
+        "wake/wake_freertos.cpp": {
+            PlatformFramework.ESP32_ARDUINO,
+            PlatformFramework.ESP32_IDF,
+            PlatformFramework.BK72XX_ARDUINO,
+            PlatformFramework.RTL87XX_ARDUINO,
+            PlatformFramework.LN882X_ARDUINO,
+        },
+        "wake/wake_esp8266.cpp": {
+            PlatformFramework.ESP8266_ARDUINO,
+        },
+        "wake/wake_rp2040.cpp": {
+            PlatformFramework.RP2040_ARDUINO,
+        },
+        "wake/wake_host.cpp": {
+            PlatformFramework.HOST_NATIVE,
+        },
+        "wake/wake_zephyr.cpp": {
+            PlatformFramework.NRF52_ZEPHYR,
+        },
         # Note: lock_free_queue.h and event_pool.h are header files and don't need to be filtered
         # as they are only included when needed by the preprocessor
     }
diff --git a/esphome/core/defines.h b/esphome/core/defines.h
index f929b224ca..93f4307e12 100644
--- a/esphome/core/defines.h
+++ b/esphome/core/defines.h
@@ -17,8 +17,21 @@
 #define ESPHOME_DEBUG_SCHEDULER
 #define ESPHOME_DEBUG_API
 
-// Default threading model for static analysis (ESP32 is multi-threaded with atomics)
+// Threading model for static analysis. Match what the real codegen picks per
+// platform (see esphome/components/<platform>/__init__.py ThreadModel.*):
+//   USE_ESP8266 / USE_RP2040 / USE_NRF52 → SINGLE
+//   USE_BK72XX (ARMv5TE, no LDREX/STREX) → MULTI_NO_ATOMICS
+//   everything else (ESP32, host, RTL87XX, LN882X) → MULTI_ATOMICS
+// Without this the clang-tidy envs end up with USE_<single-threaded platform>
+// + MULTI_ATOMICS simultaneously, a combination that can never occur in a
+// real build.
+#if defined(USE_ESP8266) || defined(USE_RP2040) || defined(USE_NRF52)
+#define ESPHOME_THREAD_SINGLE
+#elif defined(USE_BK72XX)
+#define ESPHOME_THREAD_MULTI_NO_ATOMICS
+#else
 #define ESPHOME_THREAD_MULTI_ATOMICS
+#endif
 
 // logger
 #define ESPHOME_LOG_LEVEL ESPHOME_LOG_LEVEL_VERY_VERBOSE
@@ -83,6 +96,7 @@
 #define USE_LVGL_CHECKBOX
 #define USE_LVGL_DROPDOWN
 #define USE_LVGL_FONT
+#define USE_LVGL_GRADIENT
 #define USE_LVGL_IMAGE
 #define USE_LVGL_IMAGEBUTTON
 #define USE_LVGL_KEY_LISTENER
@@ -132,6 +146,7 @@
 #define USE_NEXTION_WAVEFORM
 #define USE_NUMBER
 #define USE_OUTPUT
+#define USE_OUTPUT_FLOAT_POWER_SCALING
 #define USE_POWER_SUPPLY
 #define USE_PREFERENCES_SYNC_EVERY_LOOP
 #define USE_QR_CODE
@@ -282,6 +297,7 @@
 #define USE_CAPTIVE_PORTAL_GZIP
 #define USE_WIFI_11KV_SUPPORT
 #define USE_WIFI_FAST_CONNECT
+#define USE_WIFI_PHY_MODE
 #define USE_WIFI_IP_STATE_LISTENERS
 #define USE_WIFI_SCAN_RESULTS_LISTENERS
 #define USE_WIFI_CONNECT_STATE_LISTENERS
diff --git a/esphome/core/finite_set_mask.h b/esphome/core/finite_set_mask.h
index 616c69353d..272337ff76 100644
--- a/esphome/core/finite_set_mask.h
+++ b/esphome/core/finite_set_mask.h
@@ -55,7 +55,7 @@ template<typename ValueType, int MaxBits> struct DefaultBitPolicy {
 ///
 template<typename ValueType, typename BitPolicy = DefaultBitPolicy<ValueType, 16>> class FiniteSetMask {
  public:
-  using bitmask_t = typename BitPolicy::mask_t;
+  using bitmask_t = BitPolicy::mask_t;
 
   constexpr FiniteSetMask() = default;
 
diff --git a/esphome/core/hal.h b/esphome/core/hal.h
index e4083622b9..4babda807d 100644
--- a/esphome/core/hal.h
+++ b/esphome/core/hal.h
@@ -2,125 +2,43 @@
 #include <string>
 #include <cstdint>
 #include "gpio.h"
+#include "esphome/core/defines.h"
+#include "esphome/core/time_64.h"
+#include "esphome/core/time_conversion.h"
 
+// Per-platform HAL bits (IRAM_ATTR / PROGMEM macros, in_isr_context(),
+// inline yield/delay/micros/millis/millis_64 wrappers, ESP8266 progmem
+// helpers) live next to each platform component as components/<platform>/hal.h
+// and are dispatched here based on the active USE_* platform define. Each
+// header guards its body with the matching #ifdef USE_<platform> and re-enters
+// namespace esphome {} so it is safe to be re-included.
 #if defined(USE_ESP32)
-#include <esp_attr.h>
-#ifndef PROGMEM
-#define PROGMEM
-#endif
-
+#include "esphome/components/esp32/hal.h"
 #elif defined(USE_ESP8266)
-
-#include <c_types.h>
-#ifndef PROGMEM
-#define PROGMEM ICACHE_RODATA_ATTR
-#endif
-
-#elif defined(USE_RP2040)
-
-#define IRAM_ATTR __attribute__((noinline, long_call, section(".time_critical")))
-#define PROGMEM
-
+#include "esphome/components/esp8266/hal.h"
 #elif defined(USE_LIBRETINY)
-
-// IRAM_ATTR places a function in executable RAM so it is callable from an
-// ISR even while flash is busy (XIP stall, OTA, logger flash write).
-// Each family uses a section its stock linker already routes to RAM:
-// RTL8710B → .image2.ram.text, RTL8720C → .sram.text. LN882H is the
-// exception: its stock linker has no matching glob, so patch_linker.py
-// injects KEEP(*(.sram.text*)) into .flash_copysection at pre-link.
-//
-// BK72xx (all variants) are left as a no-op: their SDK wraps flash
-// operations in GLOBAL_INT_DISABLE() which masks FIQ + IRQ at the CPU for
-// the duration of every write, so no ISR fires while flash is stalled and
-// the race IRAM_ATTR guards against cannot occur. The trade-off is that
-// interrupts are delayed (not dropped) by up to ~20 ms during a sector
-// erase, but that is an SDK-level choice and cannot be changed from this
-// layer.
-#if defined(USE_BK72XX)
-#define IRAM_ATTR
-#elif defined(USE_LIBRETINY_VARIANT_RTL8710B)
-// Stock linker consumes *(.image2.ram.text*) into .ram_image2.text (> BD_RAM).
-#define IRAM_ATTR __attribute__((noinline, section(".image2.ram.text")))
+#include "esphome/components/libretiny/hal.h"
+#elif defined(USE_RP2040)
+#include "esphome/components/rp2040/hal.h"
+#elif defined(USE_HOST)
+#include "esphome/components/host/hal.h"
+#elif defined(USE_ZEPHYR)
+#include "esphome/components/zephyr/hal.h"
 #else
-// RTL8720C: stock linker consumes *(.sram.text*) into .ram.code_text.
-// LN882H: patch_linker.py.script injects *(.sram.text*) into
-// .flash_copysection (> RAM0 AT> FLASH).
-#define IRAM_ATTR __attribute__((noinline, section(".sram.text")))
-#endif
-#define PROGMEM
-
-#else
-
-#define IRAM_ATTR
-#define PROGMEM
-
-#endif
-
-#ifdef USE_ESP32
-#include <freertos/FreeRTOS.h>
-#include <freertos/task.h>
-#endif
-
-#ifdef USE_BK72XX
-// Declared in the Beken FreeRTOS port (portmacro.h) and built in ARM mode so
-// it is callable from Thumb code via interworking. The MRS CPSR instruction
-// is ARM-only and user code here may be built in Thumb, so in_isr_context()
-// defers to this port helper on BK72xx instead of reading CPSR inline.
-extern "C" uint32_t platform_is_in_interrupt_context(void);
+#error "hal.h: not implemented for this platform"
 #endif
 
 namespace esphome {
 
-/// Returns true when executing inside an interrupt handler.
-/// always_inline so callers placed in IRAM keep the detection in IRAM.
-__attribute__((always_inline)) inline bool in_isr_context() {
-#if defined(USE_ESP32)
-  return xPortInIsrContext() != 0;
-#elif defined(USE_ESP8266)
-  // ESP8266 has no reliable single-register ISR detection: PS.INTLEVEL is
-  // non-zero both in a real ISR and when user code masks interrupts.  The
-  // ESP8266 wake path is context-agnostic (wake_loop_impl uses esp_schedule
-  // which is ISR-safe) so this helper is unused on this platform.
-  return false;
-#elif defined(USE_RP2040)
-  uint32_t ipsr;
-  __asm__ volatile("mrs %0, ipsr" : "=r"(ipsr));
-  return ipsr != 0;
-#elif defined(USE_BK72XX)
-  // BK72xx is ARM968E-S (ARM9); see extern declaration above.
-  return platform_is_in_interrupt_context() != 0;
-#elif defined(USE_LIBRETINY)
-  // Cortex-M (AmebaZ, AmebaZ2, LN882H). IPSR is the active exception number;
-  // non-zero means we're in a handler.
-  uint32_t ipsr;
-  __asm__ volatile("mrs %0, ipsr" : "=r"(ipsr));
-  return ipsr != 0;
-#else
-  // Host and any future platform without an ISR concept.
-  return false;
-#endif
-}
-
-void yield();
-uint32_t millis();
-uint64_t millis_64();
-uint32_t micros();
-void delay(uint32_t ms);
-void delayMicroseconds(uint32_t us);  // NOLINT(readability-identifier-naming)
+// Cross-platform declarations. delayMicroseconds(), arch_feed_wdt(),
+// arch_get_cpu_cycle_count(), arch_init(), arch_get_cpu_freq_hz() vary
+// per platform (some inline, some out-of-line) so they live in
+// components/<platform>/hal.h.
 void __attribute__((noreturn)) arch_restart();
-void arch_init();
-void arch_feed_wdt();
-uint32_t arch_get_cpu_cycle_count();
-uint32_t arch_get_cpu_freq_hz();
 
-#ifdef USE_ESP8266
-// ESP8266: pgm_read_* does real flash reads on Harvard architecture
-uint8_t progmem_read_byte(const uint8_t *addr);
-const char *progmem_read_ptr(const char *const *addr);
-uint16_t progmem_read_uint16(const uint16_t *addr);
-#else
-// All other platforms: PROGMEM is a no-op, so these are direct dereferences
+#ifndef USE_ESP8266
+// All non-ESP8266 platforms: PROGMEM is a no-op, so these are direct dereferences.
+// ESP8266's out-of-line declarations live in components/esp8266/hal.h.
 inline uint8_t progmem_read_byte(const uint8_t *addr) { return *addr; }
 inline const char *progmem_read_ptr(const char *const *addr) { return *addr; }
 inline uint16_t progmem_read_uint16(const uint16_t *addr) { return *addr; }
diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index e71da95e6b..1eb3345491 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -663,8 +663,8 @@ float gamma_uncorrect(float value, float gamma) {
 }
 
 void rgb_to_hsv(float red, float green, float blue, int &hue, float &saturation, float &value) {
-  float max_color_value = std::max(std::max(red, green), blue);
-  float min_color_value = std::min(std::min(red, green), blue);
+  float max_color_value = std::max({red, green, blue});
+  float min_color_value = std::min({red, green, blue});
   float delta = max_color_value - min_color_value;
 
   if (delta == 0) {
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index 4a91c46074..07bcb7a74f 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -20,6 +20,7 @@
 #include <strings.h>
 
 #include "esphome/core/optional.h"
+#include "esphome/core/time_conversion.h"
 
 // Backward compatibility re-export of heap-allocating helpers.
 // These functions have moved to alloc_helpers.h. External components should
@@ -833,43 +834,9 @@ template<std::integral T> constexpr uint32_t fnv1a_hash_extend(uint32_t hash, T
 constexpr uint32_t fnv1a_hash(const char *str) { return fnv1a_hash_extend(FNV1_OFFSET_BASIS, str); }
 inline uint32_t fnv1a_hash(const std::string &str) { return fnv1a_hash(str.c_str()); }
 
-/// Convert a 64-bit microsecond count to milliseconds without calling
-/// __udivdi3 (software 64-bit divide, ~1200 ns on Xtensa @ 240 MHz).
-///
-/// Returns uint32_t by default (for millis()), or uint64_t when requested
-/// (for millis_64()). The only difference is whether hi * Q is truncated
-/// to 32 bits or widened to 64.
-///
-/// On 32-bit targets, GCC does not optimize 64-bit constant division into a
-/// multiply-by-reciprocal. Since 1000 = 8 * 125, we first right-shift by 3
-/// (free divide-by-8), then use the Euclidean division identity to decompose
-/// the remaining 64-bit divide-by-125 into a single 32-bit division:
-///
-///   floor(us / 1000) = floor(floor(us / 8) / 125)    [exact for integers]
-///   2^32 = Q * 125 + R  (34359738 * 125 + 46)
-///   (hi * 2^32 + lo) / 125 = hi * Q + (hi * R + lo) / 125
-///
-/// GCC optimizes the remaining 32-bit "/ 125U" into a multiply-by-reciprocal
-/// (mulhu + shift), so no division instruction is emitted.
-///
-/// Safe for us up to ~3.2e18 (~101,700 years of microseconds).
-///
-/// See: https://en.wikipedia.org/wiki/Euclidean_division
-/// See: https://ridiculousfish.com/blog/posts/labor-of-division-episode-iii.html
-template<typename ReturnT = uint32_t> inline constexpr ESPHOME_ALWAYS_INLINE ReturnT micros_to_millis(uint64_t us) {
-  constexpr uint32_t d = 125U;
-  constexpr uint32_t q = static_cast<uint32_t>((1ULL << 32) / d);  // 34359738
-  constexpr uint32_t r = static_cast<uint32_t>((1ULL << 32) % d);  // 46
-  // 1000 = 8 * 125; divide-by-8 is a free shift
-  uint64_t x = us >> 3;
-  uint32_t lo = static_cast<uint32_t>(x);
-  uint32_t hi = static_cast<uint32_t>(x >> 32);
-  // Combine remainder term: hi * (2^32 % 125) + lo
-  uint32_t adj = hi * r + lo;
-  // If adj overflowed, the true value is 2^32 + adj; apply the identity again
-  // static_cast<ReturnT>(hi) widens to 64-bit when ReturnT=uint64_t, preserving upper bits of hi*q
-  return static_cast<ReturnT>(hi) * q + (adj < lo ? (adj + r) / d + q : adj / d);
-}
+// micros_to_millis<>() lives in its own lightweight header so hal.h can pull it
+// in for inline millis_64() without forcing every TU that includes hal.h to
+// also include the rest of helpers.h.
 
 /// Return a random 32-bit unsigned integer.
 /// Not thread-safe. Must only be called from the main loop.
@@ -1666,7 +1633,7 @@ template<typename... Ts> struct Callback<void(Ts...)> {
   void *ctx_{nullptr};
 
   /// Invoke the callback. Only valid on Callbacks created via create(), never on default-constructed instances.
-  void call(Ts... args) const { this->fn_(this->ctx_, args...); }
+  void call(Ts... args) const { this->fn_(this->ctx_, std::forward<Ts>(args)...); }
 
   /// Create from any callable. Small trivially-copyable callables (like [this] lambdas)
   /// are stored inline in the ctx pointer without heap allocation.
@@ -1742,7 +1709,7 @@ template<typename... Ts> class CallbackManager<void(Ts...)> {
   template<typename F> void add(F &&callback) { this->add_(CbType::create(std::forward<F>(callback))); }
 
   /// Call all callbacks in this manager.
-  inline void ESPHOME_ALWAYS_INLINE call(Ts... args) {
+  inline void ESPHOME_ALWAYS_INLINE call(const Ts &...args) {
     if (this->size_ != 0) {
       for (auto *it = this->data_, *end = it + this->size_; it != end; ++it) {
         it->call(args...);
@@ -1752,7 +1719,7 @@ template<typename... Ts> class CallbackManager<void(Ts...)> {
   uint16_t size() const { return this->size_; }
 
   /// Call all callbacks in this manager.
-  void operator()(Ts... args) { this->call(args...); }
+  void operator()(const Ts &...args) { this->call(args...); }
 
  protected:
   template<typename...> friend class LazyCallbackManager;
@@ -2078,7 +2045,8 @@ void delay_microseconds_safe(uint32_t us);
  * Returns `nullptr` in case no memory is available.
  *
  * By setting flags, it can be configured to:
- * - perform external allocation falling back to main memory if SPI RAM is full or unavailable
+ * - perform external allocation falling back to internal memory if SPI RAM is full or unavailable (default)
+ * - perform internal allocation falling back to external memory (with PREFER_INTERNAL)
  * - perform external allocation only
  * - perform internal allocation only
  */
@@ -2087,16 +2055,26 @@ template<class T> class RAMAllocator {
   using value_type = T;
 
   enum Flags {
-    NONE = 0,                 // Perform external allocation and fall back to internal memory
-    ALLOC_EXTERNAL = 1 << 0,  // Perform external allocation only.
-    ALLOC_INTERNAL = 1 << 1,  // Perform internal allocation only.
-    ALLOW_FAILURE = 1 << 2,   // Does nothing. Kept for compatibility.
+    NONE = 0,                  // Perform external allocation and fall back to internal memory
+    ALLOC_EXTERNAL = 1 << 0,   // Perform external allocation only.
+    ALLOC_INTERNAL = 1 << 1,   // Perform internal allocation only.
+    ALLOW_FAILURE = 1 << 2,    // Does nothing. Kept for compatibility.
+    PREFER_INTERNAL = 1 << 3,  // Perform internal allocation and fall back to external memory
   };
 
   constexpr RAMAllocator() = default;
-  constexpr RAMAllocator(uint8_t flags)
-      : flags_((flags & (ALLOC_INTERNAL | ALLOC_EXTERNAL)) != 0 ? (flags & (ALLOC_INTERNAL | ALLOC_EXTERNAL))
-                                                                : (ALLOC_INTERNAL | ALLOC_EXTERNAL)) {}
+  constexpr RAMAllocator(uint8_t flags) {
+    if (flags & PREFER_INTERNAL) {
+      this->flags_ = ALLOC_INTERNAL | ALLOC_EXTERNAL | PREFER_INTERNAL;
+      return;
+    }
+    const uint8_t alloc_bits = flags & (ALLOC_INTERNAL | ALLOC_EXTERNAL);
+    if (alloc_bits != 0) {
+      this->flags_ = alloc_bits;
+      return;
+    }
+    this->flags_ = ALLOC_INTERNAL | ALLOC_EXTERNAL;
+  }
   template<class U> constexpr RAMAllocator(const RAMAllocator<U> &other) : flags_{other.flags_} {}
 
   T *allocate(size_t n) { return this->allocate(n, sizeof(T)); }
@@ -2105,12 +2083,8 @@ template<class T> class RAMAllocator {
     size_t size = n * manual_size;
     T *ptr = nullptr;
 #ifdef USE_ESP32
-    if (this->flags_ & Flags::ALLOC_EXTERNAL) {
-      ptr = static_cast<T *>(heap_caps_malloc(size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT));
-    }
-    if (ptr == nullptr && this->flags_ & Flags::ALLOC_INTERNAL) {
-      ptr = static_cast<T *>(heap_caps_malloc(size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT));
-    }
+    const auto caps = this->get_caps_();
+    ptr = static_cast<T *>(heap_caps_malloc_prefer(size, 2, caps[0], caps[1]));
 #else
     // Ignore ALLOC_EXTERNAL/ALLOC_INTERNAL flags if external allocation is not supported
     ptr = static_cast<T *>(malloc(size));  // NOLINT(cppcoreguidelines-owning-memory,cppcoreguidelines-no-malloc)
@@ -2124,12 +2098,8 @@ template<class T> class RAMAllocator {
     size_t size = n * manual_size;
     T *ptr = nullptr;
 #ifdef USE_ESP32
-    if (this->flags_ & Flags::ALLOC_EXTERNAL) {
-      ptr = static_cast<T *>(heap_caps_realloc(p, size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT));
-    }
-    if (ptr == nullptr && this->flags_ & Flags::ALLOC_INTERNAL) {
-      ptr = static_cast<T *>(heap_caps_realloc(p, size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT));
-    }
+    const auto caps = this->get_caps_();
+    ptr = static_cast<T *>(heap_caps_realloc_prefer(p, size, 2, caps[0], caps[1]));
 #else
     // Ignore ALLOC_EXTERNAL/ALLOC_INTERNAL flags if external allocation is not supported
     ptr = static_cast<T *>(realloc(p, size));  // NOLINT(cppcoreguidelines-owning-memory,cppcoreguidelines-no-malloc)
@@ -2180,6 +2150,24 @@ template<class T> class RAMAllocator {
   }
 
  private:
+#ifdef USE_ESP32
+  /// Returns {primary_caps, fallback_caps} for heap_caps_*_prefer based on the configured flags.
+  /// PREFER_INTERNAL implies both regions are enabled (enforced by the constructor), so when it is set
+  /// the primary is internal and the fallback is external. Otherwise the primary is whichever region
+  /// is enabled (external preferred when both are enabled), and the fallback is the other region (or
+  /// the same region when only one is enabled, making the second attempt a no-op).
+  std::array<uint32_t, 2> get_caps_() const {
+    constexpr uint32_t external_caps = MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT;
+    constexpr uint32_t internal_caps = MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT;
+    if (this->flags_ & PREFER_INTERNAL) {
+      return {internal_caps, external_caps};
+    }
+    const uint32_t primary = (this->flags_ & ALLOC_EXTERNAL) ? external_caps : internal_caps;
+    const uint32_t fallback = (this->flags_ & ALLOC_INTERNAL) ? internal_caps : external_caps;
+    return {primary, fallback};
+  }
+#endif
+
   uint8_t flags_{ALLOC_INTERNAL | ALLOC_EXTERNAL};
 };
 
diff --git a/esphome/core/lwip_fast_select.h b/esphome/core/lwip_fast_select.h
index 3b5e449148..4ba2606d76 100644
--- a/esphome/core/lwip_fast_select.h
+++ b/esphome/core/lwip_fast_select.h
@@ -26,25 +26,23 @@ extern "C" {
 struct lwip_sock *esphome_lwip_get_sock(int fd);
 
 /// Check if a cached LwIP socket has data ready via unlocked hint read of rcvevent.
-/// This avoids lwIP core lock contention between the main loop (CPU0) and
-/// streaming/networking work (CPU1). Correctness is preserved because callers
-/// already handle EWOULDBLOCK on nonblocking sockets — a stale hint simply causes
-/// a harmless retry on the next loop iteration. In practice, stale reads have not
-/// been observed across multi-day testing, but the design does not depend on that.
-///
-/// The sock pointer must have been obtained from esphome_lwip_get_sock() and must
-/// remain valid (caller owns socket lifetime — no concurrent close).
-/// Hot path: inlined volatile 16-bit load — no function call overhead.
-/// Uses offset-based access because lwip/priv/sockets_priv.h conflicts with C++.
+/// On ESPHOME_THREAD_MULTI_ATOMICS builds, the caller must run on the main
+/// loop task after Application::loop's per-iter std::atomic_thread_fence
+/// (memory_order_acquire); that fence pairs with the TCP/IP thread's
+/// SYS_ARCH_UNPROTECT release, so a plain load suffices and avoids the
+/// per-call `memw` that volatile would emit on Xtensa under default
+/// -mserialize-volatile. Without atomics (e.g. BK72xx), the fence is skipped
+/// and the volatile load provides ordering on its own.
+/// Stale reads are harmless either way: the hooked event_callback
+/// xTaskNotifyGives on RCVPLUS, so the next iteration re-snapshots and
+/// ulTaskNotifyTake never loses a wake.
 /// The offset and size are verified at compile time in lwip_fast_select.c.
 static inline bool esphome_lwip_socket_has_data(struct lwip_sock *sock) {
-  // Unlocked hint read — no lwIP core lock needed.
-  // volatile prevents the compiler from caching/reordering this cross-thread read.
-  // The write side (TCP/IP thread) commits via SYS_ARCH_UNPROTECT which releases a
-  // FreeRTOS mutex (ESP32) or resumes the scheduler (LibreTiny), ensuring the value
-  // is visible. Aligned 16-bit reads are single-instruction loads (L16SI/LH/LDRH) on
-  // Xtensa/RISC-V/ARM and cannot produce torn values.
+#ifdef ESPHOME_THREAD_MULTI_ATOMICS
+  return *(int16_t *) ((char *) sock + (int) ESPHOME_LWIP_SOCK_RCVEVENT_OFFSET) > 0;
+#else
   return *(volatile int16_t *) ((char *) sock + (int) ESPHOME_LWIP_SOCK_RCVEVENT_OFFSET) > 0;
+#endif
 }
 
 /// Hook a socket's netconn callback to notify the main loop task on receive events.
diff --git a/esphome/core/preference_backend.h b/esphome/core/preference_backend.h
index 3766934da4..431de205af 100644
--- a/esphome/core/preference_backend.h
+++ b/esphome/core/preference_backend.h
@@ -69,6 +69,10 @@ template<typename Derived> class PreferencesMixin {
   ESPPreferenceObject make_preference(uint32_t type) {
     return static_cast<Derived *>(this)->make_preference(sizeof(T), type);
   }
+
+ private:
+  PreferencesMixin() = default;
+  friend Derived;
 };
 
 // Macro for platform preferences.h headers to declare the standard aliases.
diff --git a/esphome/core/ring_buffer.cpp b/esphome/core/ring_buffer.cpp
index 6a2232599f..2e0802eceb 100644
--- a/esphome/core/ring_buffer.cpp
+++ b/esphome/core/ring_buffer.cpp
@@ -1,11 +1,9 @@
 #include "ring_buffer.h"
 
-#include "esphome/core/helpers.h"
-#include "esphome/core/log.h"
-
 #ifdef USE_ESP32
 
-#include "helpers.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
 
 namespace esphome {
 
@@ -19,12 +17,15 @@ RingBuffer::~RingBuffer() {
   }
 }
 
-std::unique_ptr<RingBuffer> RingBuffer::create(size_t len) {
+std::unique_ptr<RingBuffer> RingBuffer::create(size_t len, MemoryPreference preference) {
   std::unique_ptr<RingBuffer> rb = make_unique<RingBuffer>();
 
   rb->size_ = len;
 
-  RAMAllocator<uint8_t> allocator;
+  const uint8_t type = (preference == MemoryPreference::INTERNAL_FIRST) ? RAMAllocator<uint8_t>::PREFER_INTERNAL
+                                                                        : RAMAllocator<uint8_t>::NONE;
+
+  RAMAllocator<uint8_t> allocator(type);
   rb->storage_ = allocator.allocate(rb->size_);
   if (rb->storage_ == nullptr) {
     return nullptr;
diff --git a/esphome/core/ring_buffer.h b/esphome/core/ring_buffer.h
index 98a273781f..4acd07d5b0 100644
--- a/esphome/core/ring_buffer.h
+++ b/esphome/core/ring_buffer.h
@@ -80,7 +80,12 @@ class RingBuffer {
    */
   BaseType_t reset();
 
-  static std::unique_ptr<RingBuffer> create(size_t len);
+  enum class MemoryPreference {
+    EXTERNAL_FIRST,  // External RAM preferred, fall back to internal (default)
+    INTERNAL_FIRST,  // Internal RAM preferred, fall back to external
+  };
+
+  static std::unique_ptr<RingBuffer> create(size_t len, MemoryPreference preference = MemoryPreference::EXTERNAL_FIRST);
 
  protected:
   /// @brief Discards data from the ring buffer.
diff --git a/esphome/core/scheduler.cpp b/esphome/core/scheduler.cpp
index d83d67d6e4..57deeab0da 100644
--- a/esphome/core/scheduler.cpp
+++ b/esphome/core/scheduler.cpp
@@ -35,7 +35,9 @@ static constexpr uint32_t MAX_INTERVAL_DELAY = 5000;
 // Uses a stack buffer to avoid heap allocation
 // Uses ESPHOME_snprintf_P/ESPHOME_PSTR for ESP8266 to keep format strings in flash
 struct SchedulerNameLog {
-  char buffer[20];  // Enough for "id:4294967295" or "hash:0xFFFFFFFF" or "(null)"
+  // Sized for the widest formatted output: "self:0x" + 16 hex digits (64-bit pointer) + nul.
+  // Also covers "id:4294967295", "hash:0xFFFFFFFF", "iid:4294967295", "(null)".
+  char buffer[28];
 
   // Format a scheduler item name for logging
   // Returns pointer to formatted string (either static_name or internal buffer)
@@ -53,9 +55,15 @@ struct SchedulerNameLog {
     } else if (name_type == NameType::NUMERIC_ID) {
       ESPHOME_snprintf_P(buffer, sizeof(buffer), ESPHOME_PSTR("id:%" PRIu32), hash_or_id);
       return buffer;
-    } else {  // NUMERIC_ID_INTERNAL
+    } else if (name_type == NameType::NUMERIC_ID_INTERNAL) {
       ESPHOME_snprintf_P(buffer, sizeof(buffer), ESPHOME_PSTR("iid:%" PRIu32), hash_or_id);
       return buffer;
+    } else {  // SELF_POINTER
+      // static_name carries the void* key for SELF_POINTER (pointer-width union slot).
+      // %p is specified as void* (not const void*), so strip const for the varargs call.
+      ESPHOME_snprintf_P(buffer, sizeof(buffer), ESPHOME_PSTR("self:%p"),
+                         const_cast<void *>(static_cast<const void *>(static_name)));
+      return buffer;
     }
   }
 };
@@ -293,6 +301,27 @@ bool HOT Scheduler::cancel_interval(Component *component, uint32_t id) {
   return this->cancel_item_(component, NameType::NUMERIC_ID, nullptr, id, SchedulerItem::INTERVAL);
 }
 
+// Self-keyed scheduler API. The cancellation key is `self` (typically the caller's `this`),
+// passed through the existing static_name pointer slot. Matching is by raw pointer equality
+// (see matches_item_locked_'s SELF_POINTER branch). No Component pointer is stored, so
+// is_failed() skip and component-based log attribution don't apply.
+void HOT Scheduler::set_timeout(const void *self, uint32_t timeout, std::function<void()> &&func) {
+  this->set_timer_common_(nullptr, SchedulerItem::TIMEOUT, NameType::SELF_POINTER, static_cast<const char *>(self), 0,
+                          timeout, std::move(func));
+}
+void HOT Scheduler::set_interval(const void *self, uint32_t interval, std::function<void()> &&func) {
+  this->set_timer_common_(nullptr, SchedulerItem::INTERVAL, NameType::SELF_POINTER, static_cast<const char *>(self), 0,
+                          interval, std::move(func));
+}
+bool HOT Scheduler::cancel_timeout(const void *self) {
+  return this->cancel_item_(nullptr, NameType::SELF_POINTER, static_cast<const char *>(self), 0,
+                            SchedulerItem::TIMEOUT);
+}
+bool HOT Scheduler::cancel_interval(const void *self) {
+  return this->cancel_item_(nullptr, NameType::SELF_POINTER, static_cast<const char *>(self), 0,
+                            SchedulerItem::INTERVAL);
+}
+
 // Suppress deprecation warnings for RetryResult usage in the still-present (but deprecated) retry implementation.
 // Remove before 2026.8.0 along with all retry code.
 #pragma GCC diagnostic push
@@ -772,6 +801,8 @@ Scheduler::SchedulerItem *HOT Scheduler::pop_raw_locked_() {
 // Helper to execute a scheduler item
 uint32_t HOT Scheduler::execute_item_(SchedulerItem *item, uint32_t now) {
   App.set_current_component(item->component);
+  // Freshen so callbacks reading App.get_loop_component_start_time() see this item's dispatch time.
+  App.set_loop_component_start_time_(now);
   WarnIfComponentBlockingGuard guard{item->component, now};
   item->callback();
   uint32_t end = guard.finish();
diff --git a/esphome/core/scheduler.h b/esphome/core/scheduler.h
index 46b19855c3..7a6be6bea9 100644
--- a/esphome/core/scheduler.h
+++ b/esphome/core/scheduler.h
@@ -146,22 +146,43 @@ class Scheduler {
   }
 
   // Name storage type discriminator for SchedulerItem
-  // Used to distinguish between static strings, hashed strings, numeric IDs, and internal numeric IDs
+  // Used to distinguish between static strings, hashed strings, numeric IDs, internal numeric IDs,
+  // and self-keyed pointers (caller-supplied `void *`, typically `this`).
   enum class NameType : uint8_t {
-    STATIC_STRING = 0,       // const char* pointer to static/flash storage
-    HASHED_STRING = 1,       // uint32_t FNV-1a hash of a runtime string
-    NUMERIC_ID = 2,          // uint32_t numeric identifier (component-level)
-    NUMERIC_ID_INTERNAL = 3  // uint32_t numeric identifier (core/internal, separate namespace)
+    STATIC_STRING = 0,        // const char* pointer to static/flash storage
+    HASHED_STRING = 1,        // uint32_t FNV-1a hash of a runtime string
+    NUMERIC_ID = 2,           // uint32_t numeric identifier (component-level)
+    NUMERIC_ID_INTERNAL = 3,  // uint32_t numeric identifier (core/internal, separate namespace)
+    SELF_POINTER = 4          // void* caller-supplied key (typically `this`); pointer equality
   };
 
+  /** Self-keyed timeout. The cancellation key is `self` (typically the caller's `this`).
+   *
+   * Use this when the caller schedules at most one timer of a single purpose at a time and
+   * does not need a `Component` for `is_failed()` skip or log source attribution. Lets
+   * small classes drop `Component` inheritance entirely when their only Component dependency
+   * was the per-instance scheduler key.
+   *
+   * NOT applied for self-keyed items:
+   *  - `is_failed()` skip — callbacks always fire (no Component to consult).
+   *  - Log source attribution — logs use a generic "self:0x…" label.
+   *
+   * If you need either of those, use the existing `(Component *, id)` overloads.
+   */
+  void set_timeout(const void *self, uint32_t timeout, std::function<void()> &&func);
+  /// Self-keyed interval. See set_timeout(const void *, ...) for semantics.
+  void set_interval(const void *self, uint32_t interval, std::function<void()> &&func);
+  bool cancel_timeout(const void *self);
+  bool cancel_interval(const void *self);
+
  protected:
   struct SchedulerItem {
     // Ordered by size to minimize padding
     Component *component;
     // Optimized name storage using tagged union - zero heap allocation
     union {
-      const char *static_name;  // For STATIC_STRING (string literals, no allocation)
-      uint32_t hash_or_id;      // For HASHED_STRING or NUMERIC_ID
+      const char *static_name;  // For STATIC_STRING (string literals) and SELF_POINTER (caller's `this`)
+      uint32_t hash_or_id;      // For HASHED_STRING, NUMERIC_ID, and NUMERIC_ID_INTERNAL
     } name_;
     uint32_t interval;
     // Split time to handle millis() rollover. The scheduler combines the 32-bit millis()
@@ -182,19 +203,19 @@ class Scheduler {
     // std::atomic<uint8_t> inlines correctly on all platforms.
     std::atomic<uint8_t> remove{0};
 
-    // Bit-packed fields (4 bits used, 4 bits padding in 1 byte)
-    enum Type : uint8_t { TIMEOUT, INTERVAL } type : 1;
-    NameType name_type_ : 2;  // Discriminator for name_ union (0–3, see NameType enum)
-    bool is_retry : 1;        // True if this is a retry timeout
-                              // 4 bits padding
-#else
-    // Single-threaded or multi-threaded without atomics: can pack all fields together
     // Bit-packed fields (5 bits used, 3 bits padding in 1 byte)
     enum Type : uint8_t { TIMEOUT, INTERVAL } type : 1;
-    bool remove : 1;
-    NameType name_type_ : 2;  // Discriminator for name_ union (0–3, see NameType enum)
+    NameType name_type_ : 3;  // Discriminator for name_ union (0–4, see NameType enum)
     bool is_retry : 1;        // True if this is a retry timeout
                               // 3 bits padding
+#else
+    // Single-threaded or multi-threaded without atomics: can pack all fields together
+    // Bit-packed fields (6 bits used, 2 bits padding in 1 byte)
+    enum Type : uint8_t { TIMEOUT, INTERVAL } type : 1;
+    bool remove : 1;
+    NameType name_type_ : 3;  // Discriminator for name_ union (0–4, see NameType enum)
+    bool is_retry : 1;        // True if this is a retry timeout
+                              // 2 bits padding
 #endif
 
     // Constructor
@@ -228,19 +249,26 @@ class Scheduler {
     SchedulerItem(SchedulerItem &&) = delete;
     SchedulerItem &operator=(SchedulerItem &&) = delete;
 
-    // Helper to get the static name (only valid for STATIC_STRING type)
-    const char *get_name() const { return (name_type_ == NameType::STATIC_STRING) ? name_.static_name : nullptr; }
+    // Helper to get the pointer-slot value (valid for STATIC_STRING and SELF_POINTER types).
+    // Both share the same union member, so callers (e.g. log formatters) can read either uniformly.
+    const char *get_name() const {
+      return (name_type_ == NameType::STATIC_STRING || name_type_ == NameType::SELF_POINTER) ? name_.static_name
+                                                                                             : nullptr;
+    }
 
-    // Helper to get the hash or numeric ID (only valid for HASHED_STRING or NUMERIC_ID types)
-    uint32_t get_name_hash_or_id() const { return (name_type_ != NameType::STATIC_STRING) ? name_.hash_or_id : 0; }
+    // Helper to get the hash or numeric ID (only valid for HASHED_STRING / NUMERIC_ID / NUMERIC_ID_INTERNAL types)
+    uint32_t get_name_hash_or_id() const {
+      return (name_type_ != NameType::STATIC_STRING && name_type_ != NameType::SELF_POINTER) ? name_.hash_or_id : 0;
+    }
 
     // Helper to get the name type
     NameType get_name_type() const { return name_type_; }
 
-    // Set name storage: for STATIC_STRING stores the pointer, for all other types stores hash_or_id.
-    // Both union members occupy the same offset, so only one store is needed.
+    // Set name storage. STATIC_STRING/SELF_POINTER use the static_name pointer slot
+    // (both are pointer-width); other types use hash_or_id. Both union members occupy
+    // the same offset, so only one store is needed.
     void set_name(NameType type, const char *static_name, uint32_t hash_or_id) {
-      if (type == NameType::STATIC_STRING) {
+      if (type == NameType::STATIC_STRING || type == NameType::SELF_POINTER) {
         name_.static_name = static_name;
       } else {
         name_.hash_or_id = hash_or_id;
@@ -367,10 +395,14 @@ class Scheduler {
     // Name type must match
     if (item->get_name_type() != name_type)
       return false;
-    // For static strings, compare the string content; for hash/ID, compare the value
+    // STATIC_STRING: compare string content. SELF_POINTER: raw pointer equality (no strcmp).
+    // Other types: compare hash/ID value.
     if (name_type == NameType::STATIC_STRING) {
       return this->names_match_static_(item->get_name(), static_name);
     }
+    if (name_type == NameType::SELF_POINTER) {
+      return item->name_.static_name == static_name;
+    }
     return item->get_name_hash_or_id() == hash_or_id;
   }
 
diff --git a/esphome/core/time_64.cpp b/esphome/core/time_64.cpp
index cf651c3e91..25076228d5 100644
--- a/esphome/core/time_64.cpp
+++ b/esphome/core/time_64.cpp
@@ -22,8 +22,8 @@ static const char *const TAG = "time_64";
 
 #ifdef ESPHOME_THREAD_SINGLE
 // Storage for Millis64Impl inline compute() — defined here so all TUs share one copy.
-uint32_t Millis64Impl::last_millis_{0};
-uint16_t Millis64Impl::millis_major_{0};
+uint32_t Millis64Impl::last_millis{0};
+uint16_t Millis64Impl::millis_major{0};
 #else
 
 uint64_t Millis64Impl::compute(uint32_t now) {
diff --git a/esphome/core/time_64.h b/esphome/core/time_64.h
index 592e645d41..f66f9afddb 100644
--- a/esphome/core/time_64.h
+++ b/esphome/core/time_64.h
@@ -6,8 +6,6 @@
 #include <cstdint>
 #include <limits>
 
-#include "esphome/core/helpers.h"
-
 namespace esphome {
 
 class Scheduler;
@@ -21,26 +19,28 @@ class Millis64Impl {
 
 #ifdef ESPHOME_THREAD_SINGLE
   // Storage defined in time_64.cpp — declared here so the inline body can access them.
-  static uint32_t last_millis_;
-  static uint16_t millis_major_;
+  static uint32_t last_millis;
+  static uint16_t millis_major;
 
-  static inline uint64_t ESPHOME_ALWAYS_INLINE compute(uint32_t now) {
+  // Raw __attribute__((always_inline)) (not ESPHOME_ALWAYS_INLINE) so this
+  // header does not need to pull helpers.h.
+  static inline uint64_t __attribute__((always_inline)) compute(uint32_t now) {
     // Half the 32-bit range - used to detect rollovers vs normal time progression
     static constexpr uint32_t HALF_MAX_UINT32 = std::numeric_limits<uint32_t>::max() / 2;
 
     // Single-core platforms have no concurrency, so this is a simple implementation
     // that just tracks 32-bit rollover (every 49.7 days) without any locking or atomics.
-    uint16_t major = millis_major_;
-    uint32_t last = last_millis_;
+    uint16_t major = millis_major;
+    uint32_t last = last_millis;
 
     // Check for rollover
     if (now < last && (last - now) > HALF_MAX_UINT32) {
-      millis_major_++;
+      millis_major++;
       major++;
-      last_millis_ = now;
+      last_millis = now;
     } else if (now > last) {
       // Only update if time moved forward
-      last_millis_ = now;
+      last_millis = now;
     }
 
     // Combine major (high 32 bits) and now (low 32 bits) into 64-bit time
diff --git a/esphome/core/time_conversion.h b/esphome/core/time_conversion.h
new file mode 100644
index 0000000000..e9060c0626
--- /dev/null
+++ b/esphome/core/time_conversion.h
@@ -0,0 +1,46 @@
+#pragma once
+
+#include <cstdint>
+
+namespace esphome {
+
+/// Convert a 64-bit microsecond count to milliseconds without calling
+/// __udivdi3 (software 64-bit divide, ~1200 ns on Xtensa @ 240 MHz).
+///
+/// Returns uint32_t by default (for millis()), or uint64_t when requested
+/// (for millis_64()). The only difference is whether hi * Q is truncated
+/// to 32 bits or widened to 64.
+///
+/// On 32-bit targets, GCC does not optimize 64-bit constant division into a
+/// multiply-by-reciprocal. Since 1000 = 8 * 125, we first right-shift by 3
+/// (free divide-by-8), then use the Euclidean division identity to decompose
+/// the remaining 64-bit divide-by-125 into a single 32-bit division:
+///
+///   floor(us / 1000) = floor(floor(us / 8) / 125)    [exact for integers]
+///   2^32 = Q * 125 + R  (34359738 * 125 + 46)
+///   (hi * 2^32 + lo) / 125 = hi * Q + (hi * R + lo) / 125
+///
+/// GCC optimizes the remaining 32-bit "/ 125U" into a multiply-by-reciprocal
+/// (mulhu + shift), so no division instruction is emitted.
+///
+/// Safe for us up to ~3.2e18 (~101,700 years of microseconds).
+///
+/// See: https://en.wikipedia.org/wiki/Euclidean_division
+/// See: https://ridiculousfish.com/blog/posts/labor-of-division-episode-iii.html
+template<typename ReturnT = uint32_t>
+__attribute__((always_inline)) inline constexpr ReturnT micros_to_millis(uint64_t us) {
+  constexpr uint32_t d = 125U;
+  constexpr uint32_t q = static_cast<uint32_t>((1ULL << 32) / d);  // 34359738
+  constexpr uint32_t r = static_cast<uint32_t>((1ULL << 32) % d);  // 46
+  // 1000 = 8 * 125; divide-by-8 is a free shift
+  uint64_t x = us >> 3;
+  uint32_t lo = static_cast<uint32_t>(x);
+  uint32_t hi = static_cast<uint32_t>(x >> 32);
+  // Combine remainder term: hi * (2^32 % 125) + lo
+  uint32_t adj = hi * r + lo;
+  // If adj overflowed, the true value is 2^32 + adj; apply the identity again
+  // static_cast<ReturnT>(hi) widens to 64-bit when ReturnT=uint64_t, preserving upper bits of hi*q
+  return static_cast<ReturnT>(hi) * q + (adj < lo ? (adj + r) / d + q : adj / d);
+}
+
+}  // namespace esphome
diff --git a/esphome/core/wake.h b/esphome/core/wake.h
index 0cfca94a78..5a5d27ceff 100644
--- a/esphome/core/wake.h
+++ b/esphome/core/wake.h
@@ -3,6 +3,10 @@
 /// @file wake.h
 /// Platform-specific main loop wake primitives.
 /// Always available on all platforms — no opt-in needed.
+///
+/// The public API for callers lives here; the per-platform implementations
+/// live under esphome/core/wake/ and are included at the bottom of this file
+/// based on the active USE_* platform define.
 
 #include "esphome/core/defines.h"
 #include "esphome/core/hal.h"
@@ -11,21 +15,6 @@
 #include <atomic>
 #endif
 
-#if defined(USE_ESP32) || defined(USE_LIBRETINY)
-#include "esphome/core/main_task.h"
-#endif
-#ifdef USE_ESP8266
-#include <coredecls.h>
-#elif defined(USE_RP2040)
-#include <hardware/sync.h>
-#include <pico/time.h>
-#endif
-
-#ifdef USE_HOST
-#include <sys/select.h>
-#include <sys/socket.h>
-#endif
-
 namespace esphome {
 
 // === Wake flag for ESP8266/RP2040 ===
@@ -67,184 +56,21 @@ __attribute__((always_inline)) inline bool wake_request_take() {
 }
 #endif
 
-// === ESP32 / LibreTiny (FreeRTOS) ===
-#if defined(USE_ESP32) || defined(USE_LIBRETINY)
-
-/// Wake the main loop from any context (ISR or task).
-/// always_inline so callers placed in IRAM keep the whole wake path in IRAM.
-__attribute__((always_inline)) inline void wake_main_task_any_context() {
-  // Set the wake-requested flag BEFORE the task notification so the consumer
-  // (Application::loop() gate) is guaranteed to see it on its next gate check.
-  wake_request_set();
-  if (in_isr_context()) {
-    BaseType_t px_higher_priority_task_woken = pdFALSE;
-    esphome_main_task_notify_from_isr(&px_higher_priority_task_woken);
-#ifdef portYIELD_FROM_ISR
-    portYIELD_FROM_ISR(px_higher_priority_task_woken);
-#else
-    // ARM9 FreeRTOS port (BK72xx) does not define portYIELD_FROM_ISR; the IRQ
-    // exit sequence performs the context switch if one was requested.
-    (void) px_higher_priority_task_woken;
-#endif
-  } else {
-    esphome_main_task_notify();
-  }
-}
-
-/// IRAM_ATTR entry points — defined in wake.cpp.
-void wake_loop_isrsafe(BaseType_t *px_higher_priority_task_woken);
-void wake_loop_any_context();
-
-inline void wake_loop_threadsafe() {
-  wake_request_set();
-  esphome_main_task_notify();
-}
-
-namespace internal {
-inline void ESPHOME_ALWAYS_INLINE wakeable_delay(uint32_t ms) {
-  // Fast path (with USE_LWIP_FAST_SELECT): FreeRTOS task notifications posted by the lwip
-  // event_callback wrapper (see lwip_fast_select.c) are the single source of truth for
-  // socket wake-ups. Every NETCONN_EVT_RCVPLUS posts an xTaskNotifyGive, so any notification
-  // that lands between wakes keeps the counter non-zero (next ulTaskNotifyTake returns
-  // immediately) or wakes a blocked Take directly. Additional wake sources:
-  // wake_loop_threadsafe() from background tasks, and the ms timeout.
-  if (ms == 0) [[unlikely]] {
-    yield();
-    return;
-  }
-  ulTaskNotifyTake(pdTRUE, pdMS_TO_TICKS(ms));
-}
-}  // namespace internal
-
-// === ESP8266 ===
-#elif defined(USE_ESP8266)
-
-/// Inline implementation — IRAM callers inline this directly.
-inline void ESPHOME_ALWAYS_INLINE wake_loop_impl() {
-  // Set the wake-requested flag BEFORE esp_schedule so the consumer is
-  // guaranteed to see it on its next gate check.
-  wake_request_set();
-  g_main_loop_woke = true;
-  esp_schedule();
-}
-
-/// IRAM_ATTR entry point for ISR callers — defined in wake.cpp.
-void wake_loop_any_context();
-
-/// Non-ISR: always inline.
-inline void wake_loop_threadsafe() { wake_loop_impl(); }
-
-/// ISR-safe: no task_woken arg because ESP8266 has no FreeRTOS. Caller must be IRAM_ATTR.
-inline void ESPHOME_ALWAYS_INLINE wake_loop_isrsafe() { wake_loop_impl(); }
-
-namespace internal {
-inline void ESPHOME_ALWAYS_INLINE wakeable_delay(uint32_t ms) {
-  if (ms == 0) [[unlikely]] {
-    delay(0);
-    return;
-  }
-  if (g_main_loop_woke) {
-    g_main_loop_woke = false;
-    return;
-  }
-  esp_delay(ms, []() { return !g_main_loop_woke; });
-}
-}  // namespace internal
-
-// === RP2040 ===
-#elif defined(USE_RP2040)
-
-inline void wake_loop_any_context() {
-  // Set the wake-requested flag BEFORE the SEV so the consumer is guaranteed
-  // to see it on its next gate check.
-  wake_request_set();
-  g_main_loop_woke = true;
-  __sev();
-}
-
-inline void wake_loop_threadsafe() { wake_loop_any_context(); }
-
-/// RP2040 wakeable delay uses file-scope state (alarm callback + flag) — defined in wake.cpp.
-namespace internal {
-void wakeable_delay(uint32_t ms);
-}  // namespace internal
-
-// === Host / Zephyr / other ===
-#else
-
-#ifdef USE_HOST
-/// Host: wakes select() via UDP loopback socket. Defined in wake.cpp.
-void wake_loop_threadsafe();
-
-/// Register a socket file descriptor with the host select() loop. Not
-/// thread-safe — main loop only. Returns false if fd is invalid or
-/// >= FD_SETSIZE.
-bool wake_register_fd(int fd);
-
-/// Unregister a socket file descriptor. Not thread-safe — main loop only.
-void wake_unregister_fd(int fd);
-
-/// One-time setup of the loopback wake socket. Called from Application::setup().
-void wake_setup();
-
-// wake_fd_ready() and wake_drain_notifications() are defined inline at the
-// bottom of this file — they need internal::g_read_fds / g_wake_socket_fd in
-// scope, which depend on USE_HOST-only includes pulled in above.
-#else
-/// Zephyr is currently the only platform without a wake mechanism.
-/// wake_loop_threadsafe() is a no-op and wakeable_delay() falls back to delay().
-/// TODO: implement proper Zephyr wake using k_poll / k_sem or similar.
-inline void wake_loop_threadsafe() {}
-#endif
-
-inline void wake_loop_any_context() { wake_loop_threadsafe(); }
-
-namespace internal {
-#ifdef USE_HOST
-/// Host wakeable_delay uses select() over the registered fds — defined in wake.cpp.
-void wakeable_delay(uint32_t ms);
-#else
-inline void ESPHOME_ALWAYS_INLINE wakeable_delay(uint32_t ms) {
-  if (ms == 0) [[unlikely]] {
-    yield();
-    return;
-  }
-  delay(ms);
-}
-#endif
-}  // namespace internal
-
-#endif
-
-#ifdef USE_HOST
-namespace internal {
-// File-scope state owned by wake.cpp. Accessed inline by wake_drain_notifications()
-// and wake_fd_ready() so the hot path stays in the header.
-// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
-extern int g_wake_socket_fd;
-// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
-extern fd_set g_read_fds;
-}  // namespace internal
-
-inline bool ESPHOME_ALWAYS_INLINE wake_fd_ready(int fd) { return FD_ISSET(fd, &internal::g_read_fds); }
-
-// Small buffer for draining wake notification bytes (1 byte sent per wake).
-// Sized to drain multiple notifications per recvfrom() without wasting stack.
-inline constexpr size_t WAKE_NOTIFY_DRAIN_BUFFER_SIZE = 16;
-
-inline void ESPHOME_ALWAYS_INLINE wake_drain_notifications() {
-  // Called from main loop to drain any pending wake notifications.
-  // Must check wake_fd_ready() to avoid blocking on empty socket.
-  if (internal::g_wake_socket_fd >= 0 && wake_fd_ready(internal::g_wake_socket_fd)) {
-    char buffer[WAKE_NOTIFY_DRAIN_BUFFER_SIZE];
-    // Drain all pending notifications with non-blocking reads. Multiple wake events
-    // may have triggered multiple writes, so drain until EWOULDBLOCK. We control
-    // both ends of this loopback socket (always 1 byte per wake), so no error
-    // checking — any error indicates catastrophic system failure.
-    while (::recvfrom(internal::g_wake_socket_fd, buffer, sizeof(buffer), 0, nullptr, nullptr) > 0) {
-    }
-  }
-}
-#endif  // USE_HOST
-
 }  // namespace esphome
+
+// Per-platform implementations. Each header re-enters namespace esphome {} and
+// guards its body with the matching USE_* check, so only one contributes code
+// for the active target.
+#if defined(USE_ESP32) || defined(USE_LIBRETINY)
+#include "esphome/core/wake/wake_freertos.h"
+#elif defined(USE_ESP8266)
+#include "esphome/core/wake/wake_esp8266.h"
+#elif defined(USE_RP2040)
+#include "esphome/core/wake/wake_rp2040.h"
+#elif defined(USE_HOST)
+#include "esphome/core/wake/wake_host.h"
+#elif defined(USE_ZEPHYR)
+#include "esphome/core/wake/wake_zephyr.h"
+#else
+#error "wake.h: wake_loop_threadsafe() is not implemented for this platform"
+#endif
diff --git a/esphome/core/wake/wake_esp8266.cpp b/esphome/core/wake/wake_esp8266.cpp
new file mode 100644
index 0000000000..9ced43c6df
--- /dev/null
+++ b/esphome/core/wake/wake_esp8266.cpp
@@ -0,0 +1,21 @@
+#include "esphome/core/defines.h"
+
+#ifdef USE_ESP8266
+
+#include "esphome/core/hal.h"
+#include "esphome/core/wake.h"
+
+namespace esphome {
+
+// === Wake-requested flag + main-loop woke flag storage ===
+// ESP8266 is always ESPHOME_THREAD_SINGLE.
+// NOLINTBEGIN(cppcoreguidelines-avoid-non-const-global-variables)
+volatile uint8_t g_wake_requested = 0;
+volatile bool g_main_loop_woke = false;
+// NOLINTEND(cppcoreguidelines-avoid-non-const-global-variables)
+
+void IRAM_ATTR wake_loop_any_context() { wake_loop_impl(); }
+
+}  // namespace esphome
+
+#endif  // USE_ESP8266
diff --git a/esphome/core/wake/wake_esp8266.h b/esphome/core/wake/wake_esp8266.h
new file mode 100644
index 0000000000..7eaaae5293
--- /dev/null
+++ b/esphome/core/wake/wake_esp8266.h
@@ -0,0 +1,51 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_ESP8266
+
+#include "esphome/core/hal.h"
+
+#include <coredecls.h>
+
+namespace esphome {
+
+/// Inline implementation — IRAM callers inline this directly.
+inline void ESPHOME_ALWAYS_INLINE wake_loop_impl() {
+  // Set the wake-requested flag BEFORE esp_schedule so the consumer is
+  // guaranteed to see it on its next gate check.
+  wake_request_set();
+  g_main_loop_woke = true;
+  esp_schedule();
+}
+
+/// IRAM_ATTR entry point for ISR callers — defined in wake_esp8266.cpp.
+void wake_loop_any_context();
+
+/// Non-ISR: always inline.
+inline void wake_loop_threadsafe() { wake_loop_impl(); }
+
+/// ISR-safe: no task_woken arg because ESP8266 has no FreeRTOS. Caller must be IRAM_ATTR.
+inline void ESPHOME_ALWAYS_INLINE wake_loop_isrsafe() { wake_loop_impl(); }
+
+namespace internal {
+inline void ESPHOME_ALWAYS_INLINE wakeable_delay(uint32_t ms) {
+  if (ms == 0) [[unlikely]] {
+    delay(0);
+    return;
+  }
+  if (g_main_loop_woke) {
+    g_main_loop_woke = false;
+    // Yield even on the already-woken fast path so callers in tight loops
+    // (e.g. lwIP raw TCP wait_for_data_) make forward progress when ISRs
+    // keep re-setting g_main_loop_woke between iterations.
+    delay(0);
+    return;
+  }
+  esp_delay(ms, []() { return !g_main_loop_woke; });
+}
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_ESP8266
diff --git a/esphome/core/wake/wake_freertos.cpp b/esphome/core/wake/wake_freertos.cpp
new file mode 100644
index 0000000000..0bf700daa8
--- /dev/null
+++ b/esphome/core/wake/wake_freertos.cpp
@@ -0,0 +1,33 @@
+#include "esphome/core/defines.h"
+
+#if defined(USE_ESP32) || defined(USE_LIBRETINY)
+
+#include "esphome/core/hal.h"
+#include "esphome/core/wake.h"
+
+namespace esphome {
+
+// === Wake-requested flag storage ===
+// ESP32 is always MULTI_ATOMICS; LibreTiny is MULTI_ATOMICS on chips with
+// proper atomics (e.g. RTL8720) and MULTI_NO_ATOMICS on others (e.g. BK72XX).
+#ifdef ESPHOME_THREAD_MULTI_ATOMICS
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+std::atomic<uint8_t> g_wake_requested{0};
+#else
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+volatile uint8_t g_wake_requested = 0;
+#endif
+
+void IRAM_ATTR wake_loop_isrsafe(BaseType_t *px_higher_priority_task_woken) {
+  // ISR-safe: set flag before notify so the wake is visible on the next gate
+  // check. wake_request_set() is just an aligned 8-bit store / atomic store
+  // and is safe from IRAM.
+  wake_request_set();
+  esphome_main_task_notify_from_isr(px_higher_priority_task_woken);
+}
+
+void IRAM_ATTR wake_loop_any_context() { wake_main_task_any_context(); }
+
+}  // namespace esphome
+
+#endif  // USE_ESP32 || USE_LIBRETINY
diff --git a/esphome/core/wake/wake_freertos.h b/esphome/core/wake/wake_freertos.h
new file mode 100644
index 0000000000..167a422c61
--- /dev/null
+++ b/esphome/core/wake/wake_freertos.h
@@ -0,0 +1,60 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#if defined(USE_ESP32) || defined(USE_LIBRETINY)
+
+#include "esphome/core/hal.h"
+#include "esphome/core/main_task.h"
+
+namespace esphome {
+
+/// Wake the main loop from any context (ISR or task).
+/// always_inline so callers placed in IRAM keep the whole wake path in IRAM.
+__attribute__((always_inline)) inline void wake_main_task_any_context() {
+  // Set the wake-requested flag BEFORE the task notification so the consumer
+  // (Application::loop() gate) is guaranteed to see it on its next gate check.
+  wake_request_set();
+  if (in_isr_context()) {
+    BaseType_t px_higher_priority_task_woken = pdFALSE;
+    esphome_main_task_notify_from_isr(&px_higher_priority_task_woken);
+#ifdef portYIELD_FROM_ISR
+    portYIELD_FROM_ISR(px_higher_priority_task_woken);
+#else
+    // ARM9 FreeRTOS port (BK72xx) does not define portYIELD_FROM_ISR; the IRQ
+    // exit sequence performs the context switch if one was requested.
+    (void) px_higher_priority_task_woken;
+#endif
+  } else {
+    esphome_main_task_notify();
+  }
+}
+
+/// IRAM_ATTR entry points — defined in wake_freertos.cpp.
+void wake_loop_isrsafe(BaseType_t *px_higher_priority_task_woken);
+void wake_loop_any_context();
+
+inline void wake_loop_threadsafe() {
+  wake_request_set();
+  esphome_main_task_notify();
+}
+
+namespace internal {
+inline void ESPHOME_ALWAYS_INLINE wakeable_delay(uint32_t ms) {
+  // Fast path (with USE_LWIP_FAST_SELECT): FreeRTOS task notifications posted by the lwip
+  // event_callback wrapper (see lwip_fast_select.c) are the single source of truth for
+  // socket wake-ups. Every NETCONN_EVT_RCVPLUS posts an xTaskNotifyGive, so any notification
+  // that lands between wakes keeps the counter non-zero (next ulTaskNotifyTake returns
+  // immediately) or wakes a blocked Take directly. Additional wake sources:
+  // wake_loop_threadsafe() from background tasks, and the ms timeout.
+  if (ms == 0) [[unlikely]] {
+    yield();
+    return;
+  }
+  ulTaskNotifyTake(pdTRUE, pdMS_TO_TICKS(ms));
+}
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_ESP32 || USE_LIBRETINY
diff --git a/esphome/core/wake.cpp b/esphome/core/wake/wake_host.cpp
similarity index 74%
rename from esphome/core/wake.cpp
rename to esphome/core/wake/wake_host.cpp
index cac88ae91e..9d2a650ca2 100644
--- a/esphome/core/wake.cpp
+++ b/esphome/core/wake/wake_host.cpp
@@ -1,12 +1,11 @@
-#include "esphome/core/wake.h"
-#include "esphome/core/hal.h"
-#include "esphome/core/log.h"
-
-#ifdef USE_ESP8266
-#include <coredecls.h>
-#endif
+#include "esphome/core/defines.h"
 
 #ifdef USE_HOST
+
+#include "esphome/core/hal.h"
+#include "esphome/core/log.h"
+#include "esphome/core/wake.h"
+
 #include <arpa/inet.h>
 #include <cerrno>
 #include <fcntl.h>
@@ -15,88 +14,19 @@
 #include <sys/socket.h>
 #include <unistd.h>
 #include <vector>
-#endif
 
 namespace esphome {
 
 // === Wake-requested flag storage ===
-#ifdef ESPHOME_THREAD_MULTI_ATOMICS
+// Host is always ESPHOME_THREAD_MULTI_ATOMICS.
 // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
 std::atomic<uint8_t> g_wake_requested{0};
-#else
-// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
-volatile uint8_t g_wake_requested = 0;
-#endif
-
-// === ESP32 / LibreTiny — IRAM_ATTR entry points ===
-#if defined(USE_ESP32) || defined(USE_LIBRETINY)
-void IRAM_ATTR wake_loop_isrsafe(BaseType_t *px_higher_priority_task_woken) {
-  // ISR-safe: set flag before notify so the wake is visible on the next gate
-  // check. wake_request_set() is just an aligned 8-bit store / atomic store
-  // and is safe from IRAM.
-  wake_request_set();
-  esphome_main_task_notify_from_isr(px_higher_priority_task_woken);
-}
-void IRAM_ATTR wake_loop_any_context() { wake_main_task_any_context(); }
-#endif
-
-// === ESP8266 / RP2040 ===
-#if defined(USE_ESP8266) || defined(USE_RP2040)
-// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
-volatile bool g_main_loop_woke = false;
-#endif
-
-#ifdef USE_ESP8266
-void IRAM_ATTR wake_loop_any_context() { wake_loop_impl(); }
-#endif
-
-// === RP2040 — wakeable_delay (needs file-scope state for alarm callback) ===
-#ifdef USE_RP2040
-// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
-static volatile bool s_delay_expired = false;
-
-static int64_t alarm_callback_(alarm_id_t id, void *user_data) {
-  (void) id;
-  (void) user_data;
-  s_delay_expired = true;
-  __sev();
-  return 0;
-}
-
-namespace internal {
-void wakeable_delay(uint32_t ms) {
-  if (ms == 0) [[unlikely]] {
-    yield();
-    return;
-  }
-  if (g_main_loop_woke) {
-    g_main_loop_woke = false;
-    return;
-  }
-  s_delay_expired = false;
-  alarm_id_t alarm = add_alarm_in_ms(ms, alarm_callback_, nullptr, true);
-  if (alarm <= 0) {
-    delay(ms);
-    return;
-  }
-  while (!g_main_loop_woke && !s_delay_expired) {
-    __wfe();
-  }
-  if (!s_delay_expired)
-    cancel_alarm(alarm);
-  g_main_loop_woke = false;
-}
-}  // namespace internal
-#endif  // USE_RP2040
-
-// === Host (UDP loopback socket + select() based fd watcher) ===
-#ifdef USE_HOST
 
 static const char *const TAG = "wake";
 
 namespace internal {
 // File-scope state — referenced inline by wake_drain_notifications() and
-// wake_fd_ready() in wake.h, and by the bodies in this file.
+// wake_fd_ready() in wake_host.h, and by the bodies in this file.
 // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
 int g_wake_socket_fd = -1;
 // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
@@ -271,6 +201,7 @@ void wake_setup() {
     return;
   }
 }
-#endif  // USE_HOST
 
 }  // namespace esphome
+
+#endif  // USE_HOST
diff --git a/esphome/core/wake/wake_host.h b/esphome/core/wake/wake_host.h
new file mode 100644
index 0000000000..9756ed4c39
--- /dev/null
+++ b/esphome/core/wake/wake_host.h
@@ -0,0 +1,64 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_HOST
+
+#include "esphome/core/hal.h"
+
+#include <sys/select.h>
+#include <sys/socket.h>
+
+namespace esphome {
+
+/// Host: wakes select() via UDP loopback socket. Defined in wake_host.cpp.
+void wake_loop_threadsafe();
+
+/// Register a socket file descriptor with the host select() loop. Not
+/// thread-safe — main loop only. Returns false if fd is invalid or
+/// >= FD_SETSIZE.
+bool wake_register_fd(int fd);
+
+/// Unregister a socket file descriptor. Not thread-safe — main loop only.
+void wake_unregister_fd(int fd);
+
+/// One-time setup of the loopback wake socket. Called from Application::setup().
+void wake_setup();
+
+inline void wake_loop_any_context() { wake_loop_threadsafe(); }
+
+namespace internal {
+/// Host wakeable_delay uses select() over the registered fds — defined in wake_host.cpp.
+void wakeable_delay(uint32_t ms);
+
+// File-scope state owned by wake_host.cpp. Accessed inline by
+// wake_drain_notifications() and wake_fd_ready() so the hot path stays in the header.
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+extern int g_wake_socket_fd;
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+extern fd_set g_read_fds;
+}  // namespace internal
+
+inline bool ESPHOME_ALWAYS_INLINE wake_fd_ready(int fd) { return FD_ISSET(fd, &internal::g_read_fds); }
+
+// Small buffer for draining wake notification bytes (1 byte sent per wake).
+// Sized to drain multiple notifications per recvfrom() without wasting stack.
+inline constexpr size_t WAKE_NOTIFY_DRAIN_BUFFER_SIZE = 16;
+
+inline void ESPHOME_ALWAYS_INLINE wake_drain_notifications() {
+  // Called from main loop to drain any pending wake notifications.
+  // Must check wake_fd_ready() to avoid blocking on empty socket.
+  if (internal::g_wake_socket_fd >= 0 && wake_fd_ready(internal::g_wake_socket_fd)) {
+    char buffer[WAKE_NOTIFY_DRAIN_BUFFER_SIZE];
+    // Drain all pending notifications with non-blocking reads. Multiple wake events
+    // may have triggered multiple writes, so drain until EWOULDBLOCK. We control
+    // both ends of this loopback socket (always 1 byte per wake), so no error
+    // checking — any error indicates catastrophic system failure.
+    while (::recvfrom(internal::g_wake_socket_fd, buffer, sizeof(buffer), 0, nullptr, nullptr) > 0) {
+    }
+  }
+}
+
+}  // namespace esphome
+
+#endif  // USE_HOST
diff --git a/esphome/core/wake/wake_rp2040.cpp b/esphome/core/wake/wake_rp2040.cpp
new file mode 100644
index 0000000000..bdcbb1ad00
--- /dev/null
+++ b/esphome/core/wake/wake_rp2040.cpp
@@ -0,0 +1,62 @@
+#include "esphome/core/defines.h"
+
+#ifdef USE_RP2040
+
+#include "esphome/core/hal.h"
+#include "esphome/core/wake.h"
+
+#include <hardware/sync.h>
+#include <pico/time.h>
+
+namespace esphome {
+
+// === Wake-requested flag + main-loop woke flag storage ===
+// RP2040 is always ESPHOME_THREAD_SINGLE.
+// NOLINTBEGIN(cppcoreguidelines-avoid-non-const-global-variables)
+volatile uint8_t g_wake_requested = 0;
+volatile bool g_main_loop_woke = false;
+// NOLINTEND(cppcoreguidelines-avoid-non-const-global-variables)
+
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+static volatile bool s_delay_expired = false;
+
+static int64_t alarm_callback_(alarm_id_t id, void *user_data) {
+  (void) id;
+  (void) user_data;
+  s_delay_expired = true;
+  __sev();
+  return 0;
+}
+
+namespace internal {
+void wakeable_delay(uint32_t ms) {
+  if (ms == 0) [[unlikely]] {
+    yield();
+    return;
+  }
+  if (g_main_loop_woke) {
+    g_main_loop_woke = false;
+    // Yield even on the already-woken fast path so callers in tight loops
+    // (e.g. lwIP raw TCP wait_for_data_) make forward progress when async
+    // wakes keep re-setting g_main_loop_woke between iterations.
+    yield();
+    return;
+  }
+  s_delay_expired = false;
+  alarm_id_t alarm = add_alarm_in_ms(ms, alarm_callback_, nullptr, true);
+  if (alarm <= 0) {
+    delay(ms);
+    return;
+  }
+  while (!g_main_loop_woke && !s_delay_expired) {
+    __wfe();
+  }
+  if (!s_delay_expired)
+    cancel_alarm(alarm);
+  g_main_loop_woke = false;
+}
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_RP2040
diff --git a/esphome/core/wake/wake_rp2040.h b/esphome/core/wake/wake_rp2040.h
new file mode 100644
index 0000000000..ea1242f535
--- /dev/null
+++ b/esphome/core/wake/wake_rp2040.h
@@ -0,0 +1,31 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_RP2040
+
+#include "esphome/core/hal.h"
+
+#include <hardware/sync.h>
+#include <pico/time.h>
+
+namespace esphome {
+
+inline void wake_loop_any_context() {
+  // Set the wake-requested flag BEFORE the SEV so the consumer is guaranteed
+  // to see it on its next gate check.
+  wake_request_set();
+  g_main_loop_woke = true;
+  __sev();
+}
+
+inline void wake_loop_threadsafe() { wake_loop_any_context(); }
+
+/// RP2040 wakeable delay uses file-scope state (alarm callback + flag) — defined in wake_rp2040.cpp.
+namespace internal {
+void wakeable_delay(uint32_t ms);
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_RP2040
diff --git a/esphome/core/wake/wake_zephyr.cpp b/esphome/core/wake/wake_zephyr.cpp
new file mode 100644
index 0000000000..577d53f5d9
--- /dev/null
+++ b/esphome/core/wake/wake_zephyr.cpp
@@ -0,0 +1,41 @@
+#include "esphome/core/defines.h"
+
+#ifdef USE_ZEPHYR
+
+#include "esphome/core/hal.h"
+#include "esphome/core/wake.h"
+
+#include <zephyr/kernel.h>
+
+namespace esphome {
+
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+K_SEM_DEFINE(esphome_wake_sem, 0, 1);
+
+// === Wake-requested flag storage ===
+// Zephyr has preemptive threads and ISRs, so wake_loop_threadsafe() is genuinely
+// called cross-context. volatile uint8_t is sufficient because: (1) Cortex-M
+// 8-bit aligned store/load is a single non-tearing instruction, and (2) every
+// producer pairs the store with k_sem_give() (release barrier) and the consumer
+// pairs the load with k_sem_take() (acquire barrier).
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+volatile uint8_t g_wake_requested = 0;
+
+void wake_loop_threadsafe() {
+  wake_request_set();
+  k_sem_give(&esphome_wake_sem);
+}
+
+namespace internal {
+void wakeable_delay(uint32_t ms) {
+  if (ms == 0) [[unlikely]] {
+    yield();
+    return;
+  }
+  k_sem_take(&esphome_wake_sem, ms == UINT32_MAX ? K_FOREVER : K_MSEC(ms));
+}
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_ZEPHYR
diff --git a/esphome/core/wake/wake_zephyr.h b/esphome/core/wake/wake_zephyr.h
new file mode 100644
index 0000000000..c89cfc68e9
--- /dev/null
+++ b/esphome/core/wake/wake_zephyr.h
@@ -0,0 +1,28 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_ZEPHYR
+
+#include "esphome/core/hal.h"
+
+namespace esphome {
+
+/// Zephyr: wakes the main loop via k_sem_give(). Thread- and ISR-safe.
+/// Defined in wake_zephyr.cpp.
+void wake_loop_threadsafe();
+
+inline void wake_loop_any_context() { wake_loop_threadsafe(); }
+
+/// ISR-safe: no task_woken arg because Zephyr's k_sem_give() does its own ISR
+/// scheduling. Forwards to wake_loop_threadsafe().
+inline void wake_loop_isrsafe() { wake_loop_threadsafe(); }
+
+namespace internal {
+/// Zephyr wakeable_delay uses k_sem_take() with a timeout — defined in wake_zephyr.cpp.
+void wakeable_delay(uint32_t ms);
+}  // namespace internal
+
+}  // namespace esphome
+
+#endif  // USE_ZEPHYR
diff --git a/esphome/dashboard/util/text.py b/esphome/dashboard/util/text.py
index 2a3b9042e6..bdf9abfdb9 100644
--- a/esphome/dashboard/util/text.py
+++ b/esphome/dashboard/util/text.py
@@ -1,9 +1,15 @@
+"""Back-compat shim for ``friendly_name_slugify``.
+
+The function moved to :mod:`esphome.helpers` so it survives the legacy
+dashboard's eventual removal — see the
+``esphome.helpers.friendly_name_slugify`` docstring. This module
+re-exports the name so existing
+``from esphome.dashboard.util.text import friendly_name_slugify``
+imports keep working while downstream consumers migrate.
+"""
+
 from __future__ import annotations
 
-from esphome.helpers import slugify
+from esphome.helpers import friendly_name_slugify
 
-
-def friendly_name_slugify(value: str) -> str:
-    """Convert a friendly name to a slug with dashes instead of underscores."""
-    # First use the standard slugify, then convert underscores to dashes
-    return slugify(value).replace("_", "-")
+__all__ = ["friendly_name_slugify"]
diff --git a/esphome/espota2.py b/esphome/espota2.py
index 39f51e02e9..a45a6ef234 100644
--- a/esphome/espota2.py
+++ b/esphome/espota2.py
@@ -15,6 +15,9 @@ from typing import Any
 from esphome.core import EsphomeError
 from esphome.helpers import ProgressBar, resolve_ip_address
 
+OTA_TYPE_UPDATE_APP = 0x00
+OTA_TYPE_UPDATE_PARTITION_TABLE = 0x01
+
 RESPONSE_OK = 0x00
 RESPONSE_REQUEST_AUTH = 0x01
 RESPONSE_REQUEST_SHA256_AUTH = 0x02
@@ -27,6 +30,7 @@ RESPONSE_RECEIVE_OK = 0x44
 RESPONSE_UPDATE_END_OK = 0x45
 RESPONSE_SUPPORTS_COMPRESSION = 0x46
 RESPONSE_CHUNK_OK = 0x47
+RESPONSE_FEATURE_FLAGS = 0x48
 
 RESPONSE_ERROR_MAGIC = 0x80
 RESPONSE_ERROR_UPDATE_PREPARE = 0x81
@@ -42,6 +46,9 @@ RESPONSE_ERROR_NO_UPDATE_PARTITION = 0x8A
 RESPONSE_ERROR_MD5_MISMATCH = 0x8B
 RESPONSE_ERROR_RP2040_NOT_ENOUGH_SPACE = 0x8C
 RESPONSE_ERROR_SIGNATURE_INVALID = 0x8D
+RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE = 0x8E
+RESPONSE_ERROR_PARTITION_TABLE_VERIFY = 0x8F
+RESPONSE_ERROR_PARTITION_TABLE_UPDATE = 0x90
 RESPONSE_ERROR_UNKNOWN = 0xFF
 
 OTA_VERSION_1_0 = 1
@@ -49,9 +56,18 @@ OTA_VERSION_2_0 = 2
 
 MAGIC_BYTES = [0x6C, 0x26, 0xF7, 0x5C, 0x45]
 
-FEATURE_SUPPORTS_COMPRESSION = 0x01
-FEATURE_SUPPORTS_SHA256_AUTH = 0x02
+CLIENT_FEATURE_SUPPORTS_COMPRESSION = 0x01
+CLIENT_FEATURE_SUPPORTS_SHA256_AUTH = 0x02
+CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL = 0x04
+SERVER_FEATURE_SUPPORTS_COMPRESSION = 0x01
+SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS = 0x02
 
+# OTA types this client knows how to send. Future PRs that add bootloader/partition
+# updates extend this set. Anything outside the set is rejected up front so callers
+# of perform_ota/run_ota get a clear error instead of a post-auth 0x8E from the device.
+_SUPPORTED_OTA_TYPES: frozenset[int] = frozenset(
+    {OTA_TYPE_UPDATE_APP, OTA_TYPE_UPDATE_PARTITION_TABLE}
+)
 
 UPLOAD_BLOCK_SIZE = 8192
 UPLOAD_BUFFER_SIZE = UPLOAD_BLOCK_SIZE * 8
@@ -64,6 +80,72 @@ _AUTH_METHODS: dict[int, tuple[Callable[..., Any], int, str]] = {
     RESPONSE_REQUEST_AUTH: (hashlib.md5, 32, "MD5"),
 }
 
+# Error response code -> human-readable message (without the "Error: " prefix; check_error()
+# prepends it uniformly). Looked up by check_error() to translate a single byte from the device
+# into an OTAError. Add new error codes here rather than extending the if-chain in check_error().
+_ERROR_MESSAGES: dict[int, str] = {
+    RESPONSE_ERROR_MAGIC: "Invalid magic byte",
+    RESPONSE_ERROR_UPDATE_PREPARE: (
+        "Couldn't prepare flash memory for update. Is the binary too big? "
+        "Please try restarting the ESP."
+    ),
+    RESPONSE_ERROR_AUTH_INVALID: "Authentication invalid. Is the password correct?",
+    RESPONSE_ERROR_WRITING_FLASH: (
+        "Writing OTA data to flash memory failed. See USB logs for more information."
+    ),
+    RESPONSE_ERROR_UPDATE_END: (
+        "Finishing update failed. See the MQTT/USB logs for more information."
+    ),
+    RESPONSE_ERROR_INVALID_BOOTSTRAPPING: (
+        "Please press the reset button on the ESP. A manual reset is "
+        "required on the first OTA-Update after flashing via USB."
+    ),
+    RESPONSE_ERROR_WRONG_CURRENT_FLASH_CONFIG: (
+        "ESP has been flashed with wrong flash size. Please choose the "
+        "correct 'board' option (esp01_1m always works) and then flash over USB."
+    ),
+    RESPONSE_ERROR_WRONG_NEW_FLASH_CONFIG: (
+        "ESP does not have the requested flash size (wrong board). Please "
+        "choose the correct 'board' option (esp01_1m always works) and try "
+        "uploading again."
+    ),
+    RESPONSE_ERROR_ESP8266_NOT_ENOUGH_SPACE: (
+        "ESP does not have enough space to store OTA file. Please try "
+        "flashing a minimal firmware (remove everything except ota)"
+    ),
+    RESPONSE_ERROR_ESP32_NOT_ENOUGH_SPACE: (
+        "The OTA partition on the ESP is too small. ESPHome needs to resize "
+        "this partition, please flash over USB."
+    ),
+    RESPONSE_ERROR_NO_UPDATE_PARTITION: (
+        "The OTA partition on the ESP couldn't be found. ESPHome needs to "
+        "create this partition, please flash over USB."
+    ),
+    RESPONSE_ERROR_MD5_MISMATCH: (
+        "Application MD5 code mismatch. Please try again "
+        "or flash over USB with a good quality cable."
+    ),
+    RESPONSE_ERROR_SIGNATURE_INVALID: (
+        "Firmware signature verification failed. The firmware was not signed "
+        "with the correct key. Ensure the signing key matches the one used to build "
+        "the firmware currently running on the device."
+    ),
+    RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE: (
+        "The requested OTA type is not supported by the device."
+    ),
+    RESPONSE_ERROR_PARTITION_TABLE_VERIFY: (
+        "The partition table update could not be verified. No changes were "
+        "made to the flash content. Check the logs for more information and retry."
+    ),
+    RESPONSE_ERROR_PARTITION_TABLE_UPDATE: (
+        "An error occurred while updating the partition table. The device is now "
+        "in a degraded state (NVS handles are invalid; many components will fail) "
+        "and may not be able to boot. Check the logs, reboot the device, and "
+        "retry the update. If the device fails to boot, recover it via a serial flash."
+    ),
+    RESPONSE_ERROR_UNKNOWN: "Unknown error from ESP",
+}
+
 
 class OTAError(EsphomeError):
     pass
@@ -130,8 +212,10 @@ def check_error(data: list[int] | bytes, expect: int | list[int] | None) -> None
     :param expect: Expected response code(s), None to skip validation.
     :raises OTAError: If an error code is detected or response doesn't match expected.
     """
-    if expect is None:
-        return
+    # Detect device errors and connection-closed cases regardless of `expect`. If we
+    # only ran these checks when expect was set, error bytes returned during
+    # accept-any-response reads (e.g. feature negotiation, auth nonces) would be
+    # silently passed through and surface later as cryptic decode/timeout failures.
     if not data:
         raise OTAError(
             "Error: Device closed connection without responding. "
@@ -139,69 +223,11 @@ def check_error(data: list[int] | bytes, expect: int | list[int] | None) -> None
             "a network issue, or the connection was interrupted."
         )
     dat = data[0]
-    if dat == RESPONSE_ERROR_MAGIC:
-        raise OTAError("Error: Invalid magic byte")
-    if dat == RESPONSE_ERROR_UPDATE_PREPARE:
-        raise OTAError(
-            "Error: Couldn't prepare flash memory for update. Is the binary too big? "
-            "Please try restarting the ESP."
-        )
-    if dat == RESPONSE_ERROR_AUTH_INVALID:
-        raise OTAError("Error: Authentication invalid. Is the password correct?")
-    if dat == RESPONSE_ERROR_WRITING_FLASH:
-        raise OTAError(
-            "Error: Writing OTA data to flash memory failed. See USB logs for more "
-            "information."
-        )
-    if dat == RESPONSE_ERROR_UPDATE_END:
-        raise OTAError(
-            "Error: Finishing update failed. See the MQTT/USB logs for more "
-            "information."
-        )
-    if dat == RESPONSE_ERROR_INVALID_BOOTSTRAPPING:
-        raise OTAError(
-            "Error: Please press the reset button on the ESP. A manual reset is "
-            "required on the first OTA-Update after flashing via USB."
-        )
-    if dat == RESPONSE_ERROR_WRONG_CURRENT_FLASH_CONFIG:
-        raise OTAError(
-            "Error: ESP has been flashed with wrong flash size. Please choose the "
-            "correct 'board' option (esp01_1m always works) and then flash over USB."
-        )
-    if dat == RESPONSE_ERROR_WRONG_NEW_FLASH_CONFIG:
-        raise OTAError(
-            "Error: ESP does not have the requested flash size (wrong board). Please "
-            "choose the correct 'board' option (esp01_1m always works) and try "
-            "uploading again."
-        )
-    if dat == RESPONSE_ERROR_ESP8266_NOT_ENOUGH_SPACE:
-        raise OTAError(
-            "Error: ESP does not have enough space to store OTA file. Please try "
-            "flashing a minimal firmware (remove everything except ota)"
-        )
-    if dat == RESPONSE_ERROR_ESP32_NOT_ENOUGH_SPACE:
-        raise OTAError(
-            "Error: The OTA partition on the ESP is too small. ESPHome needs to resize "
-            "this partition, please flash over USB."
-        )
-    if dat == RESPONSE_ERROR_NO_UPDATE_PARTITION:
-        raise OTAError(
-            "Error: The OTA partition on the ESP couldn't be found. ESPHome needs to create "
-            "this partition, please flash over USB."
-        )
-    if dat == RESPONSE_ERROR_MD5_MISMATCH:
-        raise OTAError(
-            "Error: Application MD5 code mismatch. Please try again "
-            "or flash over USB with a good quality cable."
-        )
-    if dat == RESPONSE_ERROR_SIGNATURE_INVALID:
-        raise OTAError(
-            "Error: Firmware signature verification failed. The firmware was not signed "
-            "with the correct key. Ensure the signing key matches the one used to build "
-            "the firmware currently running on the device."
-        )
-    if dat == RESPONSE_ERROR_UNKNOWN:
-        raise OTAError("Unknown error from ESP")
+    error_msg = _ERROR_MESSAGES.get(dat)
+    if error_msg is not None:
+        raise OTAError(f"Error: {error_msg}")
+    if expect is None:
+        return
     if not isinstance(expect, (list, tuple)):
         expect = [expect]
     if dat not in expect:
@@ -232,8 +258,25 @@ def send_check(
 
 
 def perform_ota(
-    sock: socket.socket, password: str | None, file_handle: io.IOBase, filename: Path
+    sock: socket.socket,
+    password: str | None,
+    file_handle: io.IOBase,
+    filename: Path,
+    ota_type: int = OTA_TYPE_UPDATE_APP,
 ) -> None:
+    # Validate ota_type up front. It travels as a single byte on the wire, and
+    # passing an out-of-range value would only surface as a ValueError from
+    # bytes([ota_type]) deep inside send_check, bypassing OTAError handling.
+    if not isinstance(ota_type, int) or not 0 <= ota_type <= 0xFF:
+        raise OTAError(
+            f"Invalid ota_type {ota_type!r}; expected an integer in range 0-255"
+        )
+    if ota_type not in _SUPPORTED_OTA_TYPES:
+        supported = ", ".join(f"0x{t:02X}" for t in sorted(_SUPPORTED_OTA_TYPES))
+        raise OTAError(
+            f"Unsupported OTA type 0x{ota_type:02X}; this ESPHome supports: {supported}"
+        )
+
     file_contents = file_handle.read()
     file_size = len(file_contents)
     _LOGGER.info("Uploading %s (%s bytes)", filename, file_size)
@@ -251,7 +294,11 @@ def perform_ota(
         )
 
     # Features - send both compression and SHA256 auth support
-    features_to_send = FEATURE_SUPPORTS_COMPRESSION | FEATURE_SUPPORTS_SHA256_AUTH
+    features_to_send = (
+        CLIENT_FEATURE_SUPPORTS_COMPRESSION
+        | CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+        | CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
+    )
     send_check(sock, features_to_send, "features")
     features = receive_exactly(
         sock,
@@ -260,7 +307,36 @@ def perform_ota(
         None,  # Accept any response
     )[0]
 
-    if features == RESPONSE_SUPPORTS_COMPRESSION:
+    extended_proto = False
+    if features == RESPONSE_FEATURE_FLAGS:
+        extended_proto = True
+        features = receive_exactly(
+            sock,
+            1,
+            "feature flags",
+            None,  # Accept any response
+        )[0]
+    elif features == RESPONSE_SUPPORTS_COMPRESSION:
+        features = SERVER_FEATURE_SUPPORTS_COMPRESSION
+    else:
+        features = 0
+
+    if ota_type != OTA_TYPE_UPDATE_APP:
+        # Any non-app OTA type requires the extended protocol and the
+        # partition-access server feature. Reject up front so the user gets
+        # a clear capability error instead of a post-auth 0x8E from the device.
+        if not extended_proto:
+            raise OTAError(
+                f"Device does not support extended OTA protocol; "
+                f"OTA type 0x{ota_type:02X} requires it"
+            )
+        if not (features & SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS):
+            raise OTAError(
+                f"Device does not support partition access; "
+                f"OTA type 0x{ota_type:02X} cannot be used"
+            )
+
+    if features & SERVER_FEATURE_SUPPORTS_COMPRESSION:
         upload_contents = gzip.compress(file_contents, compresslevel=9)
         _LOGGER.info("Compressed to %s bytes", len(upload_contents))
     else:
@@ -315,6 +391,9 @@ def perform_ota(
     # Timeout must match device-side OTA_SOCKET_TIMEOUT_DATA to prevent premature failures
     sock.settimeout(90.0)
 
+    if extended_proto:
+        send_check(sock, ota_type, "ota type")
+
     upload_size = len(upload_contents)
     upload_size_encoded = [
         (upload_size >> 24) & 0xFF,
@@ -375,7 +454,11 @@ def perform_ota(
 
 
 def run_ota_impl_(
-    remote_host: str | list[str], remote_port: int, password: str | None, filename: Path
+    remote_host: str | list[str],
+    remote_port: int,
+    password: str | None,
+    filename: Path,
+    ota_type: int = OTA_TYPE_UPDATE_APP,
 ) -> tuple[int, str | None]:
     from esphome.core import CORE
 
@@ -413,7 +496,7 @@ def run_ota_impl_(
         _LOGGER.info("Connected to %s", sa[0])
         with open(filename, "rb") as file_handle:
             try:
-                perform_ota(sock, password, file_handle, filename)
+                perform_ota(sock, password, file_handle, filename, ota_type)
             except OTAError as err:
                 _LOGGER.error(str(err))
                 return 1, None
@@ -428,10 +511,14 @@ def run_ota_impl_(
 
 
 def run_ota(
-    remote_host: str | list[str], remote_port: int, password: str | None, filename: Path
+    remote_host: str | list[str],
+    remote_port: int,
+    password: str | None,
+    filename: Path,
+    ota_type: int = OTA_TYPE_UPDATE_APP,
 ) -> tuple[int, str | None]:
     try:
-        return run_ota_impl_(remote_host, remote_port, password, filename)
+        return run_ota_impl_(remote_host, remote_port, password, filename, ota_type)
     except OTAError as err:
         _LOGGER.error(err)
         return 1, None
diff --git a/esphome/external_files.py b/esphome/external_files.py
index b6f6149ebb..dfabc54f47 100644
--- a/esphome/external_files.py
+++ b/esphome/external_files.py
@@ -1,14 +1,20 @@
 from __future__ import annotations
 
+from collections.abc import Callable, Iterable
+from concurrent.futures import ThreadPoolExecutor
+import contextlib
 from datetime import UTC, datetime
 import logging
+import os
 from pathlib import Path
 
 import requests
 
 import esphome.config_validation as cv
-from esphome.const import __version__
-from esphome.core import CORE, TimePeriodSeconds
+from esphome.const import CONF_FILE, CONF_TYPE, CONF_URL, __version__
+from esphome.core import CORE, EsphomeError, TimePeriodSeconds
+from esphome.helpers import write_file
+from esphome.types import ConfigType
 
 _LOGGER = logging.getLogger(__name__)
 CODEOWNERS = ["@landonr"]
@@ -16,13 +22,75 @@ CODEOWNERS = ["@landonr"]
 NETWORK_TIMEOUT = 30
 
 IF_MODIFIED_SINCE = "If-Modified-Since"
+IF_NONE_MATCH = "If-None-Match"
+ETAG = "ETag"
 CACHE_CONTROL = "Cache-Control"
 CACHE_CONTROL_MAX_AGE = "max-age="
 CONTENT_DISPOSITION = "content-disposition"
 TEMP_DIR = "temp"
 
 
-def has_remote_file_changed(url: str, local_file_path: Path) -> bool:
+def _etag_sidecar_path(local_file_path: Path) -> Path:
+    return local_file_path.parent / f".{local_file_path.name}.etag"
+
+
+def _mtime_seconds(path: Path) -> int:
+    """Return `path`'s mtime as integer seconds.
+
+    Whole seconds is the common-denominator resolution across all
+    filesystems we run on (FAT/exFAT 2s, NTFS 100ns, APFS/ext4 ns), so
+    comparisons survive setting+reading round-trips that would lose
+    sub-second precision on lower-resolution filesystems.
+    """
+    return int(path.stat().st_mtime)
+
+
+def _read_etag(local_file_path: Path) -> str | None:
+    """Return the cached ETag if its sidecar's mtime still matches the cache
+    file's. A mismatch means the cache file was modified out-of-band, so the
+    ETag no longer describes its contents -- delete the stale sidecar and
+    return None.
+    """
+    etag_path = _etag_sidecar_path(local_file_path)
+    try:
+        if _mtime_seconds(etag_path) != _mtime_seconds(local_file_path):
+            _LOGGER.debug(
+                "ETag sidecar mtime mismatch at %s; treating as stale",
+                local_file_path,
+            )
+            etag_path.unlink()
+            return None
+        return etag_path.read_text().strip() or None
+    except OSError:
+        return None
+
+
+def _write_etag(local_file_path: Path, etag: str | None) -> None:
+    etag_path = _etag_sidecar_path(local_file_path)
+    if not etag:
+        # ETag persistence is best-effort; matches `_read_etag`'s tolerance.
+        with contextlib.suppress(OSError):
+            etag_path.unlink()
+        return
+    try:
+        write_file(etag_path, etag)
+    except EsphomeError as e:
+        _LOGGER.debug("Could not save ETag for %s: %s", local_file_path, e)
+        return
+    # Pin the sidecar's mtime to the cache file's mtime. _read_etag relies on
+    # this match to detect out-of-band edits to the cache file.
+    try:
+        file_mtime = _mtime_seconds(local_file_path)
+        os.utime(etag_path, (file_mtime, file_mtime))
+    except OSError as e:
+        _LOGGER.debug(
+            "Could not sync ETag sidecar mtime for %s: %s", local_file_path, e
+        )
+
+
+def has_remote_file_changed(
+    url: str, local_file_path: Path, timeout: int = NETWORK_TIMEOUT
+) -> bool:
     if local_file_path.exists():
         _LOGGER.debug("has_remote_file_changed: File exists at %s", local_file_path)
         try:
@@ -35,14 +103,17 @@ def has_remote_file_changed(url: str, local_file_path: Path) -> bool:
                 IF_MODIFIED_SINCE: local_modification_time_str,
                 CACHE_CONTROL: CACHE_CONTROL_MAX_AGE + "3600",
             }
+            if etag := _read_etag(local_file_path):
+                headers[IF_NONE_MATCH] = etag
             response = requests.head(
-                url, headers=headers, timeout=NETWORK_TIMEOUT, allow_redirects=True
+                url, headers=headers, timeout=timeout, allow_redirects=True
             )
 
             _LOGGER.debug(
-                "has_remote_file_changed: File %s, Local modified %s, response code %d",
+                "has_remote_file_changed: File %s, Local modified %s, ETag %s, response code %d",
                 local_file_path,
                 local_modification_time_str,
+                etag or "<none>",
                 response.status_code,
             )
 
@@ -51,6 +122,8 @@ def has_remote_file_changed(url: str, local_file_path: Path) -> bool:
                     "has_remote_file_changed: File not modified since %s",
                     local_modification_time_str,
                 )
+                if (new_etag := response.headers.get(ETAG)) and new_etag != etag:
+                    _write_etag(local_file_path, new_etag)
                 return False
             _LOGGER.debug("has_remote_file_changed: File modified")
             return True
@@ -85,7 +158,7 @@ def download_content(url: str, path: Path, timeout: int = NETWORK_TIMEOUT) -> by
     if CORE.skip_external_update and path.exists():
         _LOGGER.debug("Skipping update for %s (refresh disabled)", url)
         return path.read_bytes()
-    if not has_remote_file_changed(url, path):
+    if not has_remote_file_changed(url, path, timeout):
         _LOGGER.debug("Remote file has not changed %s", url)
         return path.read_bytes()
 
@@ -102,6 +175,11 @@ def download_content(url: str, path: Path, timeout: int = NETWORK_TIMEOUT) -> by
             headers={"User-agent": f"ESPHome/{__version__} (https://esphome.io)"},
         )
         req.raise_for_status()
+        # `.content` reads the body lazily; chunked-decode, gzip-decode,
+        # and mid-stream connection errors all surface here as
+        # RequestException subclasses, so this needs the same fall-back
+        # treatment as the request itself.
+        data = req.content
     except requests.exceptions.RequestException as e:
         if path.exists():
             _LOGGER.warning(
@@ -112,7 +190,91 @@ def download_content(url: str, path: Path, timeout: int = NETWORK_TIMEOUT) -> by
             return path.read_bytes()
         raise cv.Invalid(f"Could not download from {url}: {e}") from e
 
-    path.parent.mkdir(parents=True, exist_ok=True)
-    data = req.content
-    path.write_bytes(data)
+    write_file(path, data)
+    _write_etag(path, req.headers.get(ETAG))
     return data
+
+
+# Cap concurrent connections so a config with hundreds of remote files doesn't
+# open hundreds of sockets at once. 8 matches the requests connection-pool
+# default and the per-host connection limit browsers use, which keeps us
+# polite to the upstream host while still cutting wall time roughly 8x for
+# typical configs (a couple dozen files).
+DEFAULT_DOWNLOAD_WORKERS = 8
+
+
+def download_content_many(
+    items: Iterable[tuple[str, Path]],
+    timeout: int = NETWORK_TIMEOUT,
+    max_workers: int = DEFAULT_DOWNLOAD_WORKERS,
+) -> None:
+    """Run `download_content` for each (url, path) pair concurrently.
+
+    Wall time drops from `sum(latency)` to roughly `max(latency)` for cached
+    files where the HEAD round-trip dominates. All workers run to
+    completion before this returns; every `cv.Invalid` raised by a worker
+    is collected and surfaced together as `cv.MultipleInvalid` so the user
+    sees every broken file in a single validation pass instead of fixing
+    them one round-trip at a time.
+
+    Items are de-duplicated by `path` -- two callers asking for the same
+    cache file (e.g. the same URL referenced twice in a config) would
+    otherwise race on `download_content`'s non-atomic write. When the
+    same `path` appears more than once, the last URL wins (standard dict
+    comprehension semantics); in practice duplicate paths only arise when
+    the URL is duplicated, so the choice doesn't matter.
+    """
+    seen: dict[Path, str] = {path: url for url, path in items}
+    if not seen:
+        return
+    if len(seen) == 1:
+        path, url = next(iter(seen.items()))
+        download_content(url, path, timeout)
+        return
+
+    def _download_one(path_url: tuple[Path, str]) -> None:
+        # `seen` stores entries as (path, url) so the dict can dedupe by
+        # path; flip them back to download_content's (url, path) order.
+        path, url = path_url
+        download_content(url, path, timeout)
+
+    workers = max(1, min(max_workers, len(seen)))
+    errors: list[cv.Invalid] = []
+    with ThreadPoolExecutor(max_workers=workers) as ex:
+        futures = [ex.submit(_download_one, item) for item in seen.items()]
+        for future in futures:
+            try:
+                future.result()
+            except cv.Invalid as e:
+                errors.append(e)
+    if not errors:
+        return
+    if len(errors) == 1:
+        raise errors[0]
+    raise cv.MultipleInvalid(errors)
+
+
+# Each component that uses external_files defines its own local
+# `TYPE_WEB = "web"`; the string is repeated here rather than imported
+# because there is no canonical `TYPE_WEB` in `esphome.const` to share.
+WEB_TYPE = "web"
+
+
+def download_web_files_in_config(
+    config: list[ConfigType],
+    path_for: Callable[[ConfigType], Path],
+) -> list[ConfigType]:
+    """Voluptuous-friendly validator that downloads any web-sourced files in
+    `config` in parallel.
+
+    Each entry is expected to contain a `file` key whose value is a dict
+    that may be `{type: "web", url: ...}`; `path_for(file_dict)` returns
+    the cache path for that file. Returns `config` unchanged so it can be
+    slotted directly into a `cv.All(...)` chain.
+    """
+    download_content_many(
+        (conf_file[CONF_URL], path_for(conf_file))
+        for entry in config
+        if (conf_file := entry.get(CONF_FILE, {})).get(CONF_TYPE) == WEB_TYPE
+    )
+    return config
diff --git a/esphome/git.py b/esphome/git.py
index 4d6e14001a..0106f24845 100644
--- a/esphome/git.py
+++ b/esphome/git.py
@@ -128,7 +128,10 @@ def clone_or_update(
                 # We need to fetch the PR branch first, otherwise git will complain
                 # about missing objects
                 _LOGGER.info("Fetching %s", ref)
-                run_git_command(["git", "fetch", "--", "origin", ref], git_dir=repo_dir)
+                run_git_command(
+                    ["git", "fetch", "--depth=1", "--", "origin", ref],
+                    git_dir=repo_dir,
+                )
                 run_git_command(
                     ["git", "reset", "--hard", "FETCH_HEAD"], git_dir=repo_dir
                 )
@@ -138,7 +141,8 @@ def clone_or_update(
                     "Initializing submodules (%s) for %s", ", ".join(submodules), key
                 )
                 run_git_command(
-                    ["git", "submodule", "update", "--init"] + submodules,
+                    ["git", "submodule", "update", "--init", "--depth=1", "--"]
+                    + submodules,
                     git_dir=repo_dir,
                 )
         except GitException:
@@ -179,8 +183,13 @@ def clone_or_update(
                     git_dir=repo_dir,
                 )
 
-                # Fetch remote ref
-                cmd = ["git", "fetch", "--", "origin"]
+                # Fetch from the remote. --depth=1 keeps the clone shallow
+                # while still picking up new commits when the remote tip
+                # moves: a shallow fetch retrieves the current tip being
+                # fetched, whether that's an explicit ref or the remote's
+                # default branch, then reset --hard FETCH_HEAD updates the
+                # working tree to it.
+                cmd = ["git", "fetch", "--depth=1", "--", "origin"]
                 if ref is not None:
                     cmd.append(ref)
                 run_git_command(cmd, git_dir=repo_dir)
@@ -229,7 +238,8 @@ def clone_or_update(
                     "Updating submodules (%s) for %s", ", ".join(submodules), key
                 )
                 run_git_command(
-                    ["git", "submodule", "update", "--init"] + submodules,
+                    ["git", "submodule", "update", "--init", "--depth=1", "--"]
+                    + submodules,
                     git_dir=repo_dir,
                 )
 
diff --git a/esphome/helpers.py b/esphome/helpers.py
index f41bec357d..bb1984e17c 100644
--- a/esphome/helpers.py
+++ b/esphome/helpers.py
@@ -120,6 +120,24 @@ def slugify(value: str) -> str:
     return "".join(c for c in value if c in ALLOWED_NAME_CHARS)
 
 
+def friendly_name_slugify(value: str) -> str:
+    """Convert a friendly name to a slug with dashes instead of underscores.
+
+    Used by:
+    - esphome.dashboard.web_server (legacy dashboard)
+    - device-builder (esphome/device-builder) — slugifies friendly names
+      into the YAML filename / device name during adoption + wizard flows.
+
+    Lives here rather than in ``esphome.dashboard.util.text`` so it
+    survives the legacy dashboard's eventual removal.
+    The dashboard module re-exports this name as a back-compat shim.
+    Coordinate with the device-builder team before changing the
+    slugification rules — the mapping must stay stable so existing
+    on-disk filenames keep matching across releases.
+    """
+    return slugify(value).replace("_", "-")
+
+
 def indent_all_but_first_and_last(text, padding="  "):
     lines = text.splitlines(True)
     if len(lines) <= 2:
@@ -370,7 +388,11 @@ def rmtree(path: Path | str) -> None:
         os.chmod(path, stat.S_IWUSR | stat.S_IRUSR)
         func(path)
 
-    shutil.rmtree(path, onerror=_onerror)
+    # ``onerror`` is deprecated in 3.12 in favour of ``onexc`` (different
+    # callable signature); keep the existing handler shape for now and
+    # silence the lint locally so this PR doesn't bundle an unrelated
+    # migration.
+    shutil.rmtree(path, onerror=_onerror)  # pylint: disable=deprecated-argument
 
 
 def walk_files(path: Path):
diff --git a/esphome/idf_component.yml b/esphome/idf_component.yml
index cb7f5903cf..f5a8dd8c60 100644
--- a/esphome/idf_component.yml
+++ b/esphome/idf_component.yml
@@ -10,7 +10,7 @@ dependencies:
   esphome/micro-flac:
     version: 0.1.1
   esphome/micro-opus:
-    version: 0.3.6
+    version: 0.4.0
   espressif/esp-dsp:
     version: "1.7.1"
   espressif/esp-tflite-micro:
@@ -20,15 +20,19 @@ dependencies:
   espressif/mdns:
     version: 1.11.0
   espressif/esp_wifi_remote:
-    version: 1.4.0
+    version: 1.5.1
+    rules:
+      - if: "target in [esp32h2, esp32p4]"
+  espressif/wifi_remote_over_eppp:
+    version: 0.3.2
     rules:
       - if: "target in [esp32h2, esp32p4]"
   espressif/eppp_link:
-    version: 1.1.4
+    version: 1.1.5
     rules:
       - if: "target in [esp32h2, esp32p4]"
   espressif/esp_hosted:
-    version: 2.12.1
+    version: 2.12.6
     rules:
       - if: "target in [esp32h2, esp32p4]"
   zorxx/multipart-parser:
@@ -92,6 +96,6 @@ dependencies:
   esp32async/asynctcp:
     version: 3.4.91
   sendspin/sendspin-cpp:
-    version: 0.3.1
+    version: 0.4.0
   lvgl/lvgl:
     version: 9.5.0
diff --git a/esphome/loader.py b/esphome/loader.py
index 68664aaa26..d50554f8c9 100644
--- a/esphome/loader.py
+++ b/esphome/loader.py
@@ -9,13 +9,23 @@ import logging
 from pathlib import Path
 import sys
 from types import ModuleType
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
 from esphome.const import SOURCE_FILE_EXTENSIONS
 from esphome.core import CORE
-import esphome.core.config
 from esphome.types import ConfigType
 
+if TYPE_CHECKING:
+    from esphome.cpp_generator import MockObjClass
+
+# `esphome.core.config` is imported lazily in `_lookup_module` when the
+# "esphome" pseudo-component is first resolved. It pulls in
+# `esphome.automation` and `esphome.config_validation`, which together
+# dominate `esphome.__main__` startup cost when loaded eagerly.
+# `esphome.cpp_generator` is similarly avoided at module scope; it pulls
+# in `esphome.yaml_util` and is only needed for the `MockObjClass` type
+# annotation, which is resolved lazily via `TYPE_CHECKING`.
+
 _LOGGER = logging.getLogger(__name__)
 
 
@@ -31,8 +41,9 @@ class FileResource:
 
 
 class ComponentManifest:
-    def __init__(self, module: ModuleType):
+    def __init__(self, module: ModuleType, recursive_sources: bool = False):
         self.module = module
+        self.recursive_sources = recursive_sources
 
     @property
     def package(self) -> str:
@@ -92,7 +103,7 @@ class ComponentManifest:
         return getattr(self.module, "CODEOWNERS", [])
 
     @property
-    def instance_type(self) -> list[str]:
+    def instance_type(self) -> "MockObjClass | None":
         return getattr(self.module, "INSTANCE_TYPE", None)
 
     @property
@@ -108,8 +119,10 @@ class ComponentManifest:
     def resources(self) -> list[FileResource]:
         """Return a list of all file resources defined in the package of this component.
 
-        This will return all cpp source files that are located in the same folder as the
-        loaded .py file (does not look through subdirectories)
+        By default only files directly in the package directory are returned. Manifests
+        constructed with ``recursive_sources=True`` also descend into non-subpackage
+        subdirectories (subdirectories without an ``__init__.py``), so core code can
+        live under ``esphome/core/<group>/`` without every component paying the cost.
         """
         ret: list[FileResource] = []
 
@@ -121,23 +134,30 @@ class ComponentManifest:
             set(filter_source_files_func()) if filter_source_files_func else set()
         )
 
-        # Process all resources
-        for resource in (
-            r.name
-            for r in importlib.resources.files(self.package).iterdir()
-            if r.is_file()
-        ):
-            if Path(resource).suffix not in SOURCE_FILE_EXTENSIONS:
-                continue
-            if not importlib.resources.files(self.package).joinpath(resource).is_file():
-                # Not a resource = this is a directory (yeah this is confusing)
-                continue
+        root = importlib.resources.files(self.package)
 
-            # Skip excluded files
-            if resource in excluded_files:
-                continue
+        for child in root.iterdir():
+            name = child.name
+            if child.is_file():
+                if Path(name).suffix not in SOURCE_FILE_EXTENSIONS:
+                    continue
+                if name in excluded_files:
+                    continue
+                ret.append(FileResource(self.package, name))
+            elif self.recursive_sources and child.is_dir() and name != "__pycache__":
+                # Skip Python subpackages — they load as their own components.
+                if child.joinpath("__init__.py").is_file():
+                    continue
+                for sub in child.iterdir():
+                    if not sub.is_file():
+                        continue
+                    if Path(sub.name).suffix not in SOURCE_FILE_EXTENSIONS:
+                        continue
+                    resource = f"{name}/{sub.name}"
+                    if resource in excluded_files:
+                        continue
+                    ret.append(FileResource(self.package, resource))
 
-            ret.append(FileResource(self.package, resource))
         return ret
 
 
@@ -202,6 +222,13 @@ def _lookup_module(domain: str, exception: bool) -> ComponentManifest | None:
     if domain in _COMPONENT_CACHE:
         return _COMPONENT_CACHE[domain]
 
+    if domain == "esphome":
+        import esphome.core.config
+
+        manif = ComponentManifest(esphome.core.config, recursive_sources=True)
+        _COMPONENT_CACHE[domain] = manif
+        return manif
+
     try:
         module = importlib.import_module(f"esphome.components.{domain}")
     except ImportError as e:
@@ -237,7 +264,6 @@ def get_platform(domain: str, platform: str) -> ComponentManifest | None:
 
 _COMPONENT_CACHE: dict[str, ComponentManifest] = {}
 CORE_COMPONENTS_PATH = (Path(__file__).parent / "components").resolve()
-_COMPONENT_CACHE["esphome"] = ComponentManifest(esphome.core.config)
 
 
 def _replace_component_manifest(domain: str, manifest: ComponentManifest) -> None:
diff --git a/esphome/platformio_api.py b/esphome/platformio_api.py
index dec541985f..c0cd048890 100644
--- a/esphome/platformio_api.py
+++ b/esphome/platformio_api.py
@@ -14,6 +14,37 @@ from esphome.util import run_external_process
 _LOGGER = logging.getLogger(__name__)
 
 
+def _strip_win_long_path_prefix(path: str) -> str:
+    r"""Strip the Windows extended-length path prefix from ``path``.
+
+    Handles both forms documented at
+    https://learn.microsoft.com/windows/win32/fileio/naming-a-file:
+
+    * ``\\?\C:\path\to\file`` -> ``C:\path\to\file``
+    * ``\\?\UNC\server\share\path`` -> ``\\server\share\path``
+
+    The NSIS-installed ``esphome.exe`` launcher on Windows starts Python with
+    ``sys.executable`` already prefixed with ``\\?\``. That prefix propagates
+    into PlatformIO's ``$PYTHONEXE`` (PlatformIO reads ``PYTHONEXEPATH`` from
+    the environment, falling back to ``os.path.normpath(sys.executable)``)
+    and ends up baked into SCons-emitted command lines for build steps such
+    as the esp8266 ``elf2bin`` invocation. ``cmd.exe`` does not understand
+    the ``\\?\`` prefix, so the build fails with
+    "The system cannot find the path specified." Stripping the prefix early
+    keeps the path shell-quotable.
+
+    No-op on non-Windows platforms.
+    """
+    if sys.platform != "win32":
+        return path
+    if path.startswith("\\\\?\\UNC\\"):
+        # \\?\UNC\server\share\... -> \\server\share\...
+        return "\\\\" + path[len("\\\\?\\UNC\\") :]
+    if path.startswith("\\\\?\\"):
+        return path[len("\\\\?\\") :]
+    return path
+
+
 def run_platformio_cli(*args, **kwargs) -> str | int:
     os.environ["PLATFORMIO_FORCE_COLOR"] = "true"
     os.environ["PLATFORMIO_BUILD_DIR"] = str(CORE.relative_pioenvs_path().absolute())
@@ -24,7 +55,18 @@ def run_platformio_cli(*args, **kwargs) -> str | int:
     os.environ.setdefault("PYTHONWARNINGS", "ignore::SyntaxWarning")
     # Increase uv retry count to handle transient network errors (default is 3)
     os.environ.setdefault("UV_HTTP_RETRIES", "10")
-    cmd = [sys.executable, "-m", "esphome.platformio_runner"] + list(args)
+    # Strip the Windows extended-length path prefix from sys.executable so it
+    # doesn't propagate into PlatformIO's $PYTHONEXE and break SCons-emitted
+    # command lines run through cmd.exe.
+    python_exe = _strip_win_long_path_prefix(sys.executable)
+    if python_exe != sys.executable:
+        # Only override PYTHONEXEPATH when we actually stripped a prefix.
+        # PlatformIO's get_pythonexe_path() reads this and falls back to
+        # sys.executable otherwise; setting it unconditionally would clobber
+        # a user-provided value (or the unmodified path on platforms that
+        # don't need the strip).
+        os.environ["PYTHONEXEPATH"] = python_exe
+    cmd = [python_exe, "-m", "esphome.platformio_runner"] + list(args)
 
     return run_external_process(*cmd, **kwargs)
 
diff --git a/esphome/platformio_runner.py b/esphome/platformio_runner.py
index 599c9408a4..5b14a72557 100644
--- a/esphome/platformio_runner.py
+++ b/esphome/platformio_runner.py
@@ -101,7 +101,7 @@ def patch_file_downloader() -> None:
     FileDownloader.__init__ = patched_init
 
 
-_IGNORE_LIB_WARNINGS = f"(?:{'|'.join(['Hash', 'Update'])})"
+_IGNORE_LIB_WARNINGS = "(?:Hash|Update)"
 # Regex patterns matched against each line of PlatformIO output. Lines that
 # match are dropped by RedirectText before they reach the parent process.
 # Patterns are anchored at the start of the line (RedirectText uses
diff --git a/esphome/storage_json.py b/esphome/storage_json.py
index d5423ab1c7..c6df16ce78 100644
--- a/esphome/storage_json.py
+++ b/esphome/storage_json.py
@@ -21,6 +21,14 @@ def storage_path() -> Path:
 
 
 def ext_storage_path(config_filename: str) -> Path:
+    """Path to the per-config StorageJSON sidecar.
+
+    Used by:
+    - device-builder (esphome/device-builder) — locates the sidecar
+      to read board / framework / firmware-bin / loaded_integrations
+      info for the dashboard. Coordinate before changing the path
+      shape; device-builder reads the same file on disk.
+    """
     return CORE.data_dir / "storage" / f"{config_filename}.json"
 
 
@@ -29,6 +37,14 @@ def esphome_storage_path() -> Path:
 
 
 def ignored_devices_storage_path() -> Path:
+    """Path to the dashboard's ignored-devices list.
+
+    Used by:
+    - device-builder (esphome/device-builder) — reads the same
+      ``ignored-devices.json`` so the new dashboard's "ignore" toggle
+      stays compatible with the legacy one. Don't change the file
+      shape without coordinating.
+    """
     return CORE.data_dir / "ignored-devices.json"
 
 
@@ -46,6 +62,18 @@ def _to_path_if_not_none(value: str | None) -> Path | None:
 
 
 class StorageJSON:
+    """Persisted device metadata sidecar.
+
+    Used by:
+    - esphome.dashboard (legacy dashboard)
+    - device-builder (esphome/device-builder) — reads/writes the same
+      JSON file as the legacy dashboard so a single config_dir can be
+      shared between the two during the transition. The schema
+      (``storage_version``, field names, types) must stay backwards
+      compatible — coordinate with the device-builder team before
+      adding required fields or changing semantics of existing ones.
+    """
+
     def __init__(
         self,
         storage_version: int,
diff --git a/esphome/zeroconf.py b/esphome/zeroconf.py
index 6f5d33c808..5d922ea911 100644
--- a/esphome/zeroconf.py
+++ b/esphome/zeroconf.py
@@ -60,6 +60,18 @@ TXT_RECORD_VERSION = b"version"
 
 @dataclass
 class DiscoveredImport:
+    """An importable device discovered via mDNS ``_esphomelib._tcp.local.``.
+
+    Used by:
+    - esphome.dashboard (legacy dashboard)
+    - device-builder (esphome/device-builder) — surfaces these as
+      "discovered devices" on the new dashboard's adoption flow.
+
+    Fields are populated from TXT records on the broadcast service
+    info (see :class:`DashboardImportDiscovery`). Coordinate before
+    adding/removing fields — both consumers persist them.
+    """
+
     friendly_name: str | None
     device_name: str
     package_import_url: str
@@ -73,6 +85,22 @@ class DashboardBrowser(AsyncServiceBrowser):
 
 
 class DashboardImportDiscovery:
+    """Track importable devices announcing on ``_esphomelib._tcp.local.``.
+
+    Used by:
+    - esphome.dashboard (legacy dashboard)
+    - device-builder (esphome/device-builder) — wired up alongside
+      the dashboard's own ``ServiceBrowser`` to populate the
+      "Discovered devices" panel and the adoption flow.
+
+    The class maintains ``import_state: dict[str, DiscoveredImport]``
+    keyed by the mDNS service name. ``on_update`` is invoked with
+    ``(name, info | None)`` for additions and removals; update events
+    refresh ``import_state`` without firing the callback.
+    Coordinate before changing the callback signature or the keys
+    of ``import_state`` — device-builder reads both directly.
+    """
+
     def __init__(
         self, on_update: Callable[[str, DiscoveredImport | None], None] | None = None
     ) -> None:
@@ -232,6 +260,19 @@ async def async_resolve_hosts(
 
 
 class AsyncEsphomeZeroconf(AsyncZeroconf):
+    """ESPHome-tuned ``AsyncZeroconf`` with a hostname-resolve helper.
+
+    Used by:
+    - esphome.dashboard (legacy dashboard)
+    - device-builder (esphome/device-builder) — drives both the live
+      mDNS browser and the per-sweep ``async_resolve_host`` fallback
+      for non-API devices that don't broadcast esphomelib.
+
+    Coordinate before adding required constructor args or changing
+    the ``async_resolve_host`` signature — device-builder calls it
+    on every ping cycle.
+    """
+
     async def async_resolve_host(
         self, host: str, timeout: float = DEFAULT_TIMEOUT
     ) -> list[str] | None:
diff --git a/pyproject.toml b/pyproject.toml
index dc6785001d..d16bf2b625 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -113,6 +113,7 @@ exclude = ['generated']
 select = [
   "E",    # pycodestyle
   "F",    # pyflakes/autoflake
+  "FLY",  # flynt: convert string formatting to f-strings
   "FURB", # refurb
   "I",    # isort
   "PERF", # performance
diff --git a/requirements.txt b/requirements.txt
index abc8ac5dbb..789a3f7995 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,7 +12,7 @@ platformio==6.1.19
 esptool==5.2.0
 click==8.3.3
 esphome-dashboard==20260425.0
-aioesphomeapi==44.22.0
+aioesphomeapi==44.23.0
 zeroconf==0.148.0
 puremagic==1.30
 ruamel.yaml==0.19.1 # dashboard_import
diff --git a/requirements_dev.txt b/requirements_dev.txt
index 0884e5b5e4..31463e07c3 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,4 +1,4 @@
 # Useful stuff when working in a development environment
 clang-format==13.0.1  # also change in .pre-commit-config.yaml and Dockerfile when updating
-clang-tidy==18.1.8  # When updating clang-tidy, also update Dockerfile
+clang-tidy==22.1.0.1
 yamllint==1.38.0  # also change in .pre-commit-config.yaml when updating
diff --git a/requirements_test.txt b/requirements_test.txt
index b35025fa04..568d79d676 100644
--- a/requirements_test.txt
+++ b/requirements_test.txt
@@ -12,3 +12,6 @@ pytest-asyncio==1.3.0
 pytest-xdist==3.8.0
 asyncmock==0.4.2
 hypothesis==6.92.1
+
+# Used by the import-time regression check (.github/workflows/ci.yml → import-time job)
+importtime-waterfall==1.0.0
diff --git a/script/api_protobuf/api_protobuf.py b/script/api_protobuf/api_protobuf.py
index c10479a726..bf672d0567 100755
--- a/script/api_protobuf/api_protobuf.py
+++ b/script/api_protobuf/api_protobuf.py
@@ -184,6 +184,11 @@ class TypeInfo(ABC):
         """Check if this field should always be encoded (skip zero/empty check)."""
         return get_field_opt(self._field, pb.force, False)
 
+    @property
+    def mac_address(self) -> bool:
+        """Check if this uint64 field is a 48-bit MAC address (use 7-byte fast path)."""
+        return get_field_opt(self._field, pb.mac_address, False)
+
     @property
     def max_value(self) -> int | None:
         """Get the max_value option for this field, or None if not set."""
@@ -665,8 +670,22 @@ class UInt64Type(VarintTypeMixin, TypeInfo):
         return o
 
     def get_size_calculation(self, name: str, force: bool = False) -> str:
+        if self.mac_address and force:
+            field_id_size = self.calculate_field_id_size()
+            return (
+                f"size += ProtoSize::calc_uint64_48bit_force({field_id_size}, {name});"
+            )
         return self._get_simple_size_calculation(name, force, "uint64")
 
+    @property
+    def RAW_ENCODE_MAP(self) -> dict[str, str]:  # noqa: N802
+        if self.mac_address:
+            return {
+                **TypeInfo.RAW_ENCODE_MAP,
+                "encode_uint64": "ProtoEncode::encode_varint_raw_48bit(pos, {value});",
+            }
+        return TypeInfo.RAW_ENCODE_MAP
+
     def get_estimated_size(self) -> int:
         return self.calculate_field_id_size() + 3  # field ID + 3 bytes typical varint
 
@@ -3558,8 +3577,13 @@ static const char *const TAG = "api.service";
     # Generate read_message_ as APIConnection method (not base class) so the compiler
     # can devirtualize and inline the on_* handler calls within the same class.
     # APIConnection declares this method in api_connection.h.
+    # Guard with #ifdef USE_API since APIConnection itself is only defined when
+    # USE_API is set; without this, builds that compile this .cpp without
+    # USE_API (e.g. C++ unit tests for api dependencies) fail to find the
+    # class declaration.
 
-    out = "void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const uint8_t *msg_data) {\n"
+    out = "#ifdef USE_API\n"
+    out += "void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const uint8_t *msg_data) {\n"
 
     # Auth check block before dispatch switch
     out += "  // Check authentication/connection requirements\n"
@@ -3604,6 +3628,7 @@ static const char *const TAG = "api.service";
     out += "      break;\n"
     out += "  }\n"
     out += "}\n"
+    out += "#endif  // USE_API\n"
     cpp += out
     hpp += "};\n"
 
diff --git a/script/build_helpers.py b/script/build_helpers.py
index 1cfae51fca..0e0e8170a0 100644
--- a/script/build_helpers.py
+++ b/script/build_helpers.py
@@ -57,6 +57,59 @@ def hash_components(components: list[str]) -> str:
     return hashlib.sha256(key.encode()).hexdigest()[:16]
 
 
+def populate_dependency_config(
+    config: dict,
+    component_names: list[str],
+    *,
+    get_component_fn: Callable[[str], object | None] = get_component,
+    register_platform_fn: Callable[[str], None] | None = None,
+) -> None:
+    """Populate ``config`` with empty entries for transitive dependencies.
+
+    For every name in ``component_names``:
+
+    * ``domain.platform`` form (e.g. ``sensor.gpio``) appends
+      ``{platform: <name>}`` to ``config[domain]``, creating the list if needed.
+    * Bare components are looked up via ``get_component_fn``. Platform
+      components (``IS_PLATFORM_COMPONENT``) and ``MULTI_CONF`` components are
+      initialised as ``[]`` so the sibling ``domain.platform`` branch can
+      ``append`` into them. Everything else is populated by running the
+      component's schema with ``{}`` so defaults exist; if the schema requires
+      explicit input, an empty ``{}`` is used as a fallback.
+
+    Platform components must always be a list here even when no
+    ``domain.platform`` entry follows, because the ``domain.platform`` branch
+    does ``config.setdefault(domain, []).append(...)`` and would crash on a
+    leftover dict.
+    """
+    if register_platform_fn is None:
+        register_platform_fn = CORE.testing_ensure_platform_registered
+    for component_name in component_names:
+        if "." in component_name:
+            domain, component = component_name.split(".", maxsplit=1)
+            domain_list = config.setdefault(domain, [])
+            register_platform_fn(domain)
+            domain_list.append({CONF_PLATFORM: component})
+            continue
+        # Skip "core" — it's a pseudo-component handled by the build
+        # system, not a real loadable component (get_component returns None)
+        component = get_component_fn(component_name)
+        if component is None:
+            continue
+        if component.multi_conf or component.is_platform_component:
+            config.setdefault(component_name, [])
+        elif component_name not in config:
+            schema = component.config_schema
+            try:
+                config[component_name] = schema({}) if schema is not None else {}
+            except Exception:  # noqa: BLE001
+                # Schema requires explicit input we can't synthesize; fall
+                # back to an empty mapping so subscripting at least returns
+                # KeyError on missing keys rather than crashing on the
+                # wrong type.
+                config[component_name] = {}
+
+
 def filter_components_with_files(components: list[str], tests_dir: Path) -> list[str]:
     """Filter out components that do not have .cpp or .h files in the tests dir.
 
@@ -316,16 +369,7 @@ def compile_and_get_binary(
 
     # Add remaining components and dependencies to the configuration after
     # validation, so their source files are included in the build.
-    for component_name in components_with_dependencies:
-        if "." in component_name:
-            domain, component = component_name.split(".", maxsplit=1)
-            domain_list = config.setdefault(domain, [])
-            CORE.testing_ensure_platform_registered(domain)
-            domain_list.append({CONF_PLATFORM: component})
-        # Skip "core" — it's a pseudo-component handled by the build
-        # system, not a real loadable component (get_component returns None)
-        elif get_component(component_name) is not None:
-            config.setdefault(component_name, [])
+    populate_dependency_config(config, components_with_dependencies)
 
     # Register platforms from the extra config (benchmark.yaml) so
     # USE_SENSOR, USE_LIGHT, etc. defines are emitted without needing
diff --git a/script/check_import_time.py b/script/check_import_time.py
new file mode 100755
index 0000000000..0d5362c968
--- /dev/null
+++ b/script/check_import_time.py
@@ -0,0 +1,241 @@
+#!/usr/bin/env python3
+"""Regression check for `import esphome.__main__` cost.
+
+Runs `python -m importtime_waterfall --har esphome.__main__` (which invokes
+`-X importtime` in fresh subprocesses, best-of-N) and compares the root
+cumulative import time against a checked-in budget
+(`script/import_time_budget.json`).
+
+The CLI pays this cost on every invocation before the requested command even
+runs, so a regression here hurts every user.
+"""
+
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+import subprocess
+import sys
+from typing import Any, TextIO
+
+SCRIPT_DIR = Path(__file__).parent
+BUDGET_PATH = SCRIPT_DIR / "import_time_budget.json"
+
+TARGET_MODULE = "esphome.__main__"
+DEFAULT_MARGIN_PCT = 15
+OFFENDERS_TOP_N = 15
+
+
+def run_waterfall(module: str) -> str:
+    """Run `importtime_waterfall --har <module>` and return the HAR JSON text.
+
+    `importtime_waterfall` itself runs the target in 6 fresh subprocesses
+    under `-X importtime` and emits the HAR of the fastest run.
+    """
+    result = subprocess.run(
+        [sys.executable, "-m", "importtime_waterfall", "--har", module],
+        check=True,
+        stdout=subprocess.PIPE,
+        text=True,
+    )
+    return result.stdout
+
+
+def measure(module: str, har_path: Path | None = None) -> dict[str, Any]:
+    """Return the parsed HAR for importing `module`.
+
+    When `har_path` is given, also write the raw HAR JSON to that path so
+    callers can combine `--check` with `--har` without measuring twice.
+    """
+    har_text = run_waterfall(module)
+    if har_path is not None:
+        har_path.write_text(har_text)
+    return json.loads(har_text)
+
+
+def _entries(har: dict[str, Any]) -> list[dict[str, Any]]:
+    return har["log"]["entries"]
+
+
+def root_cumulative_us(har: dict[str, Any], module: str) -> int:
+    """Return the cumulative import time (µs) of `module` from a HAR.
+
+    The HAR `time` field is authored by importtime_waterfall using µs values
+    fed through `timedelta(milliseconds=...)`, so the number read back is the
+    original self/cumulative time in microseconds (labelled "ms" in HAR).
+    """
+    for entry in _entries(har):
+        if entry["request"]["url"] == module:
+            return entry["time"]
+    raise RuntimeError(
+        f"No HAR entry for {module!r}. Is it importable with "
+        f"`python -c 'import {module}'`?"
+    )
+
+
+def top_offenders(har: dict[str, Any], n: int) -> list[tuple[str, int, int]]:
+    """Return up to `n` (name, self_us, cumulative_us), ranked by self_us desc.
+
+    A module imported from multiple places is counted once (first entry wins,
+    matching importtime's own de-duplication).
+    """
+    seen: dict[str, tuple[int, int]] = {}
+    for entry in _entries(har):
+        name = entry["request"]["url"]
+        if name in seen:
+            continue
+        self_us = entry["timings"]["receive"]
+        cumulative_us = entry["time"]
+        seen[name] = (self_us, cumulative_us)
+    ranked = sorted(
+        ((name, s, c) for name, (s, c) in seen.items()),
+        key=lambda row: row[1],
+        reverse=True,
+    )
+    return ranked[:n]
+
+
+def read_budget() -> dict[str, Any]:
+    if not BUDGET_PATH.exists():
+        return {}
+    with BUDGET_PATH.open() as f:
+        return json.load(f)
+
+
+def write_budget(cumulative_us: int, margin_pct: int) -> None:
+    payload = {
+        "target_module": TARGET_MODULE,
+        "margin_pct": margin_pct,
+        "cumulative_us": cumulative_us,
+    }
+    with BUDGET_PATH.open("w") as f:
+        json.dump(payload, f, indent=2)
+        f.write("\n")
+
+
+def _format_us(us: int) -> str:
+    if us >= 1000:
+        return f"{us / 1000:.1f}ms"
+    return f"{us}us"
+
+
+def _print_offenders_table(
+    offenders: list[tuple[str, int, int]], stream: TextIO
+) -> None:
+    name_w = max(len(name) for name, _, _ in offenders)
+    print(f"\n{'module':<{name_w}}  {'self':>10}  {'cumulative':>12}", file=stream)
+    print(f"{'-' * name_w}  {'-' * 10}  {'-' * 12}", file=stream)
+    for name, self_us, cum_us in offenders:
+        print(
+            f"{name:<{name_w}}  {_format_us(self_us):>10}  {_format_us(cum_us):>12}",
+            file=stream,
+        )
+
+
+def cmd_check(args: argparse.Namespace) -> int:
+    budget = read_budget()
+    if not budget:
+        print(
+            f"ERROR: {BUDGET_PATH.name} missing. Run with --update first.",
+            file=sys.stderr,
+        )
+        return 2
+
+    har = measure(TARGET_MODULE, har_path=Path(args.har) if args.har else None)
+    measured = root_cumulative_us(har, TARGET_MODULE)
+
+    baseline = budget["cumulative_us"]
+    margin_pct = budget.get("margin_pct", DEFAULT_MARGIN_PCT)
+    ceiling = int(baseline * (1 + margin_pct / 100))
+
+    summary = (
+        f"measured   {TARGET_MODULE}: {_format_us(measured)} "
+        f"(budget {_format_us(baseline)} + {margin_pct}% = {_format_us(ceiling)})"
+    )
+    passed = measured <= ceiling
+    stream = sys.stdout if passed else sys.stderr
+
+    if passed:
+        print(summary)
+    else:
+        print(
+            f"REGRESSION: `import {TARGET_MODULE}` took {_format_us(measured)}, "
+            f"exceeding the budget of {_format_us(baseline)} + {margin_pct}% "
+            f"({_format_us(ceiling)}).",
+            file=stream,
+        )
+
+    print("\nTop import-time offenders (by self time):", file=stream)
+    _print_offenders_table(top_offenders(har, OFFENDERS_TOP_N), stream)
+
+    if not passed:
+        print(
+            "\nIf this regression is intentional, regenerate the budget with:\n"
+            "  script/check_import_time.py --update\n"
+            "Otherwise, consider making the new import lazy "
+            "(import inside the function that uses it).",
+            file=stream,
+        )
+        return 1
+    return 0
+
+
+def cmd_update(args: argparse.Namespace) -> int:
+    har = measure(TARGET_MODULE, har_path=Path(args.har) if args.har else None)
+    measured = root_cumulative_us(har, TARGET_MODULE)
+    write_budget(measured, args.margin_pct)
+    print(
+        f"Wrote {BUDGET_PATH.name}: "
+        f"{TARGET_MODULE}={_format_us(measured)} "
+        f"(margin {args.margin_pct}%)"
+    )
+    return 0
+
+
+def cmd_har_only(args: argparse.Namespace) -> int:
+    Path(args.har).write_text(run_waterfall(TARGET_MODULE))
+    print(f"Wrote waterfall HAR to {args.har}")
+    return 0
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        "--margin-pct",
+        type=int,
+        default=DEFAULT_MARGIN_PCT,
+        help=(f"Margin over baseline for --update (default: {DEFAULT_MARGIN_PCT}%%)."),
+    )
+    parser.add_argument(
+        "--har",
+        metavar="PATH",
+        help=(
+            "Write a waterfall HAR file at PATH. Can be combined with "
+            "--check or --update to reuse that run's measurement (avoids "
+            "measuring twice)."
+        ),
+    )
+    mode = parser.add_mutually_exclusive_group()
+    mode.add_argument(
+        "--check", action="store_true", help="Fail if measured time exceeds budget."
+    )
+    mode.add_argument(
+        "--update",
+        action="store_true",
+        help="Rewrite the budget from a fresh measurement.",
+    )
+    args = parser.parse_args()
+
+    if args.check:
+        return cmd_check(args)
+    if args.update:
+        return cmd_update(args)
+    if args.har:
+        return cmd_har_only(args)
+    parser.error("Specify at least one of --check, --update, or --har PATH.")
+    return 2  # unreachable; parser.error exits. Here to satisfy ruff RET503.
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/script/ci-custom.py b/script/ci-custom.py
index 4d71df74cf..b257a3818b 100755
--- a/script/ci-custom.py
+++ b/script/ci-custom.py
@@ -511,6 +511,40 @@ def lint_no_std_string_view(fname, match):
     )
 
 
+@lint_re_check(
+    r"(?:"
+    # `from esphome.components.const import ...`
+    r"from\s+esphome\.components\.const\s+import"
+    r"|"
+    # `import esphome.components.const` (with optional `as` alias)
+    r"import\s+esphome\.components\.const\b"
+    r"|"
+    # `from esphome.components import [(] ... const ... [)]`
+    # Handles parenthesized + multiline import lists by allowing newlines inside
+    # the parens via [^)]*. Single-line form falls back to the [^#\n]* branch.
+    r"from\s+esphome\.components\s+import\s*"
+    r"(?:\([^)]*\bconst\b[^)]*\)|(?:[^#\n]*[\s,])?\bconst\b)"
+    r")",
+    include=["*.py"],
+    exclude=[
+        "esphome/components/*",
+        "tests/*",
+        "script/ci-custom.py",
+    ],
+)
+def lint_no_components_const_outside_components(fname, match):
+    return (
+        f"Constants in {highlight('esphome/components/const/__init__.py')} are intended "
+        f"to be shared only between components in {highlight('esphome/components/')}. "
+        f"Code outside this folder must not import from "
+        f"{highlight('esphome.components.const')}.\n"
+        f"For core code (used outside {highlight('esphome/components/')}), define the "
+        f"constant in {highlight('esphome/const.py')} instead. When adding a new "
+        f"{highlight('CONF_')} constant there, bump {highlight('CONST_PY_MAX_CONF')} "
+        f"in this file accordingly (see {highlight('lint_const_py_frozen')})."
+    )
+
+
 @lint_post_check
 def lint_constants_usage():
     errs = []
diff --git a/script/clang-tidy b/script/clang-tidy
index f2834b44ac..1c413ffa23 100755
--- a/script/clang-tidy
+++ b/script/clang-tidy
@@ -295,7 +295,7 @@ def main():
 
     failed_files = []
     try:
-        executable = get_binary("clang-tidy", 18)
+        executable = get_binary("clang-tidy", 22)
         task_queue = queue.Queue(args.jobs)
         lock = threading.Lock()
         for _ in range(args.jobs):
@@ -341,13 +341,13 @@ def main():
         try:
             try:
                 subprocess.call(
-                    ["clang-apply-replacements-18", tmpdir], close_fds=False
+                    ["clang-apply-replacements-22", tmpdir], close_fds=False
                 )
             except FileNotFoundError:
                 subprocess.call(["clang-apply-replacements", tmpdir], close_fds=False)
         except FileNotFoundError:
             print(
-                "Error please install clang-apply-replacements-18 or clang-apply-replacements.\n",
+                "Error please install clang-apply-replacements-22 or clang-apply-replacements.\n",
                 file=sys.stderr,
             )
         except:
diff --git a/script/determine-jobs.py b/script/determine-jobs.py
index f036447542..b8f324784d 100755
--- a/script/determine-jobs.py
+++ b/script/determine-jobs.py
@@ -6,11 +6,11 @@ what files have changed. It outputs JSON with the following structure:
 
 {
   "integration_tests": true/false,
-  "integration_tests_run_all": true/false,
-  "integration_test_files": ["tests/integration/test_foo.py", ...],
+  "integration_test_buckets": [{"name": "1/3", "tests": ["tests/integration/test_foo.py", ...]}, ...],
   "clang_tidy": true/false,
   "clang_format": true/false,
   "python_linters": true/false,
+  "device_builder": true/false,
   "changed_components": ["component1", "component2", ...],
   "component_test_count": 5,
   "memory_impact": {
@@ -26,6 +26,7 @@ The CI workflow uses this information to:
 - Skip or run clang-tidy (and whether to do a full scan)
 - Skip or run clang-format
 - Skip or run Python linters (ruff, flake8, pylint, pyupgrade)
+- Skip or run downstream esphome/device-builder tests against the PR's Python code
 - Determine which components to test individually
 - Decide how to split component tests (if there are many)
 - Run memory impact analysis whenever there are changed components (merged config), and also for core-only changes
@@ -81,6 +82,62 @@ CLANG_TIDY_SPLIT_THRESHOLD = 65
 # Isolated components count as 10x, groupable components count as 1x
 COMPONENT_TEST_BATCH_SIZE = 40
 
+# Integration test bucketing: when more than the threshold tests are scheduled,
+# fan out across this many parallel jobs. Below the threshold, a single job runs.
+INTEGRATION_TESTS_SPLIT_THRESHOLD = 10
+INTEGRATION_TESTS_SPLIT_BUCKETS = 3
+
+
+def _split_list(items: list[str], n: int) -> list[list[str]]:
+    """Split a list into n roughly-equal contiguous parts (matches script/clang-tidy)."""
+    k, m = divmod(len(items), n)
+    return [items[i * k + min(i, m) : (i + 1) * k + min(i + 1, m)] for i in range(n)]
+
+
+def _all_integration_test_files() -> list[str]:
+    """Return all integration test file paths, sorted, relative to repo root."""
+    return sorted(
+        str(p.relative_to(root_path))
+        for p in (Path(root_path) / "tests" / "integration").glob("test_*.py")
+    )
+
+
+def _compute_integration_test_buckets(
+    integration_run_all: bool,
+    integration_test_files: list[str],
+) -> tuple[bool, list[dict[str, Any]]]:
+    """Compute (run_integration, buckets) from the determine_integration_tests result.
+
+    Pure function for unit testing — no I/O beyond `_all_integration_test_files`
+    when `integration_run_all` is set.
+
+    `buckets` is a list of `{name, tests}` dicts where `tests` is a JSON-friendly
+    list of file paths so the workflow can build a bash array via jq, avoiding
+    shell word-splitting / glob hazards.
+    """
+    if integration_run_all:
+        files = _all_integration_test_files()
+    else:
+        files = sorted(integration_test_files)
+
+    # Empty list (e.g. run_all expansion with no files on disk) would otherwise
+    # cause the workflow to invoke pytest with no path argument and collect
+    # tests outside tests/integration/. Suppress the run instead.
+    if not files:
+        return False, []
+
+    if len(files) > INTEGRATION_TESTS_SPLIT_THRESHOLD:
+        parts = [
+            part for part in _split_list(files, INTEGRATION_TESTS_SPLIT_BUCKETS) if part
+        ]
+        buckets = [
+            {"name": f"{i + 1}/{len(parts)}", "tests": part}
+            for i, part in enumerate(parts)
+        ]
+    else:
+        buckets = [{"name": "1/1", "tests": files}]
+    return True, buckets
+
 
 class Platform(StrEnum):
     """Platform identifiers for memory impact analysis."""
@@ -349,6 +406,92 @@ def should_run_python_linters(branch: str | None = None) -> bool:
     return _any_changed_file_endswith(branch, PYTHON_FILE_EXTENSIONS)
 
 
+# Files outside esphome/**/*.py whose changes can affect `import esphome.__main__`
+# cost. requirements.txt / pyproject.toml change the dependency graph pulled in
+# by top-level imports; check_import_time.py itself changes the check's behavior.
+IMPORT_TIME_TRIGGER_FILES = frozenset(
+    {
+        "requirements.txt",
+        "requirements_dev.txt",
+        "requirements_test.txt",
+        "pyproject.toml",
+        "script/check_import_time.py",
+        "script/import_time_budget.json",
+    }
+)
+
+
+def should_run_import_time(branch: str | None = None) -> bool:
+    """Determine if the `import esphome.__main__` time regression check should run.
+
+    Runs when any Python file under `esphome/` changes (those modules are
+    loaded transitively from `esphome.__main__`), when dependency
+    declarations change, or when the check script/budget itself changes.
+
+    Args:
+        branch: Branch to compare against. If None, uses default.
+
+    Returns:
+        True if the import-time check should run, False otherwise.
+    """
+    for file in changed_files(branch):
+        if file.startswith("esphome/") and file.endswith(PYTHON_FILE_EXTENSIONS):
+            return True
+        if file in IMPORT_TIME_TRIGGER_FILES:
+            return True
+    return False
+
+
+# Files outside esphome/**/*.py whose changes can affect the downstream
+# device-builder build. requirements.txt / pyproject.toml change the runtime
+# dependency graph that device-builder picks up when it installs esphome.
+DEVICE_BUILDER_TRIGGER_FILES = frozenset(
+    {
+        "requirements.txt",
+        "pyproject.toml",
+    }
+)
+
+
+def should_run_device_builder(branch: str | None = None) -> bool:
+    """Determine if downstream esphome/device-builder tests should run.
+
+    device-builder imports esphome as a library, so whenever the importable
+    Python surface, the runtime dependencies, or any non-C++ file packaged
+    with esphome (pyproject.toml has ``include-package-data = true``, so
+    things like esphome/idf_component.yml ship and can affect installs)
+    changes we re-run its test suite against the PR's code to catch
+    breakage we'd otherwise only see after a release.
+
+    Skipped on beta/release branches: those branches typically lag behind
+    device-builder@main, so a new device-builder API dependency would
+    falsely fail the run without reflecting any problem in the PR itself.
+
+    Args:
+        branch: Branch to compare against. If None, uses default.
+
+    Returns:
+        True if the device-builder downstream tests should run, False otherwise.
+    """
+    target_branch = get_target_branch()
+    if target_branch and (
+        target_branch.startswith("release") or target_branch.startswith("beta")
+    ):
+        return False
+
+    for file in changed_files(branch):
+        if file in DEVICE_BUILDER_TRIGGER_FILES:
+            return True
+        # Anything under esphome/ that isn't C++ source can change the
+        # importable / packaged surface device-builder consumes
+        # (Python sources, packaged YAML/JSON like idf_component.yml,
+        # etc.). C++ files only affect compiled firmware, not the
+        # Python install device-builder pulls in.
+        if file.startswith("esphome/") and not file.endswith(CPP_FILE_EXTENSIONS):
+            return True
+    return False
+
+
 def determine_cpp_unit_tests(
     branch: str | None = None,
 ) -> tuple[bool, list[str]]:
@@ -776,10 +919,14 @@ def main() -> None:
     integration_run_all, integration_test_files = determine_integration_tests(
         args.branch
     )
-    run_integration = integration_run_all or bool(integration_test_files)
+    run_integration, integration_test_buckets = _compute_integration_test_buckets(
+        integration_run_all, integration_test_files
+    )
     run_clang_tidy = should_run_clang_tidy(args.branch)
     run_clang_format = should_run_clang_format(args.branch)
     run_python_linters = should_run_python_linters(args.branch)
+    run_import_time = should_run_import_time(args.branch)
+    run_device_builder = should_run_device_builder(args.branch)
     changed_cpp_file_count = count_changed_cpp_files(args.branch)
 
     # Get changed components
@@ -907,12 +1054,13 @@ def main() -> None:
 
     output: dict[str, Any] = {
         "integration_tests": run_integration,
-        "integration_tests_run_all": integration_run_all,
-        "integration_test_files": integration_test_files,
+        "integration_test_buckets": integration_test_buckets,
         "clang_tidy": run_clang_tidy,
         "clang_tidy_mode": clang_tidy_mode,
         "clang_format": run_clang_format,
         "python_linters": run_python_linters,
+        "import_time": run_import_time,
+        "device_builder": run_device_builder,
         "changed_components": changed_components,
         "changed_components_with_tests": changed_components_with_tests,
         "directly_changed_components_with_tests": list(directly_changed_with_tests),
diff --git a/script/import_time_budget.json b/script/import_time_budget.json
new file mode 100644
index 0000000000..af3aa83511
--- /dev/null
+++ b/script/import_time_budget.json
@@ -0,0 +1,5 @@
+{
+  "target_module": "esphome.__main__",
+  "margin_pct": 15,
+  "cumulative_us": 91000
+}
diff --git a/tests/benchmarks/components/api/__init__.py b/tests/benchmarks/components/api/__init__.py
index eb86492964..0d02e0b054 100644
--- a/tests/benchmarks/components/api/__init__.py
+++ b/tests/benchmarks/components/api/__init__.py
@@ -11,11 +11,19 @@ def override_manifest(manifest: ComponentManifestOverride) -> None:
 
     async def to_code(config):
         await original_to_code(config)
-        # Enable BLE proto message types for benchmarks.  The real
-        # bluetooth_proxy component is ESP32-only; a lightweight stub
-        # header in tests/benchmarks/stubs/ satisfies the include.
+        # Enable proxy proto message types for benchmarks.  The real
+        # components have hardware dependencies (BLE/UART/RMT); lightweight
+        # stub headers in tests/benchmarks/stubs/ satisfy the includes.
         cg.add_define("USE_BLUETOOTH_PROXY")
         cg.add_define("BLUETOOTH_PROXY_MAX_CONNECTIONS", 3)
         cg.add_define("BLUETOOTH_PROXY_ADVERTISEMENT_BATCH_SIZE", 16)
+        cg.add_define("USE_ZWAVE_PROXY")
+        cg.add_define("USE_INFRARED")
+        cg.add_define("USE_IR_RF")
+        cg.add_define("USE_RADIO_FREQUENCY")
+        cg.add_define("USE_SERIAL_PROXY")
+        cg.add_define("SERIAL_PROXY_COUNT", 0)
+        cg.add_define("ESPHOME_ENTITY_INFRARED_COUNT", 0)
+        cg.add_define("ESPHOME_ENTITY_RADIO_FREQUENCY_COUNT", 0)
 
     manifest.to_code = to_code
diff --git a/tests/benchmarks/components/api/bench_proto_proxy.cpp b/tests/benchmarks/components/api/bench_proto_proxy.cpp
new file mode 100644
index 0000000000..fa3191a969
--- /dev/null
+++ b/tests/benchmarks/components/api/bench_proto_proxy.cpp
@@ -0,0 +1,280 @@
+// Encode/decode microbenchmarks for proxy message families that carry
+// high-volume traffic (Z-Wave, IR/RF, serial). Mirrors the existing
+// BluetoothLERawAdvertisementsResponse benchmarks in bench_proto_encode.cpp.
+
+#include <benchmark/benchmark.h>
+
+#include <cstring>
+
+#include "esphome/components/api/api_pb2.h"
+#include "esphome/components/api/api_buffer.h"
+
+namespace esphome::api::benchmarks {
+
+static constexpr int kInnerIterations = 2000;
+
+// Encodes `src` into `out`. Caller owns `out` and must keep it alive across
+// the decode loop (decoded messages may store pointers back into its bytes).
+template<typename T> static void encode_into(APIBuffer &out, const T &src) {
+  out.resize(src.calculate_size());
+  ProtoWriteBuffer writer(&out, 0);
+  src.encode(writer);
+}
+
+// --- ZWaveProxyFrame (Z-Wave frame, ~16 bytes payload) ---
+
+#ifdef USE_ZWAVE_PROXY
+
+static const uint8_t kZWaveFrameData[] = {0x01, 0x09, 0x00, 0x13, 0x01, 0x02, 0x00, 0x00,
+                                          0x25, 0x00, 0x05, 0xC4, 0x00, 0x00, 0x00, 0x00};
+
+static void Encode_ZWaveProxyFrame(benchmark::State &state) {
+  ZWaveProxyFrame msg;
+  msg.data = kZWaveFrameData;
+  msg.data_len = sizeof(kZWaveFrameData);
+  APIBuffer buffer;
+  buffer.resize(msg.calculate_size());
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
+    benchmark::DoNotOptimize(buffer.data());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Encode_ZWaveProxyFrame);
+
+static void Decode_ZWaveProxyFrame(benchmark::State &state) {
+  ZWaveProxyFrame source;
+  source.data = kZWaveFrameData;
+  source.data_len = sizeof(kZWaveFrameData);
+  APIBuffer encoded;
+  encode_into(encoded, source);
+  const uint8_t *data = encoded.data();
+  size_t size = encoded.size();
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      ZWaveProxyFrame msg;
+      msg.decode(data, size);
+      benchmark::DoNotOptimize(msg);
+    }
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Decode_ZWaveProxyFrame);
+
+static const uint8_t kZWaveRequestData[] = {0xDE, 0xAD, 0xBE, 0xEF};
+
+static void Decode_ZWaveProxyRequest(benchmark::State &state) {
+  ZWaveProxyRequest source;
+  source.type = enums::ZWAVE_PROXY_REQUEST_TYPE_HOME_ID_CHANGE;
+  source.data = kZWaveRequestData;
+  source.data_len = sizeof(kZWaveRequestData);
+  APIBuffer encoded;
+  encode_into(encoded, source);
+  const uint8_t *data = encoded.data();
+  size_t size = encoded.size();
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      ZWaveProxyRequest msg;
+      msg.decode(data, size);
+      benchmark::DoNotOptimize(msg);
+    }
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Decode_ZWaveProxyRequest);
+
+#endif  // USE_ZWAVE_PROXY
+
+// --- SerialProxyDataReceived encode + SerialProxyWriteRequest decode ---
+//
+// SerialProxyWriteRequest is decode-only (SOURCE_CLIENT) but has the same
+// wire layout as SerialProxyDataReceived, so we encode via the latter and
+// decode as the former.
+
+#ifdef USE_SERIAL_PROXY
+
+static constexpr size_t kSerialPayloadSize = 64;
+static const uint8_t kSerialPayload[kSerialPayloadSize] = {
+    0x55, 0xAA, 0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0, 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB,
+    0xCD, 0xEF, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE,
+    0xFF, 0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70, 0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0,
+    0xF0, 0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F, 0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF};
+
+static void Encode_SerialProxyDataReceived(benchmark::State &state) {
+  SerialProxyDataReceived msg;
+  msg.instance = 0;
+  msg.set_data(kSerialPayload, kSerialPayloadSize);
+  APIBuffer buffer;
+  buffer.resize(msg.calculate_size());
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
+    benchmark::DoNotOptimize(buffer.data());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Encode_SerialProxyDataReceived);
+
+static void Decode_SerialProxyWriteRequest(benchmark::State &state) {
+  SerialProxyDataReceived source;
+  source.instance = 0;
+  source.set_data(kSerialPayload, kSerialPayloadSize);
+  APIBuffer encoded;
+  encode_into(encoded, source);
+  const uint8_t *data = encoded.data();
+  size_t size = encoded.size();
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      SerialProxyWriteRequest msg;
+      msg.decode(data, size);
+      benchmark::DoNotOptimize(msg);
+    }
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Decode_SerialProxyWriteRequest);
+
+#endif  // USE_SERIAL_PROXY
+
+// --- InfraredRFReceiveEvent encode (100 sint32 timings) +
+//     InfraredRFTransmitRawTimingsRequest decode (hand-built wire bytes) ---
+
+#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+
+// Mark/space pairs simulating a typical RC-5 / NEC capture (100 timings).
+static std::vector<int32_t> make_ir_timings_100() {
+  std::vector<int32_t> v;
+  v.reserve(100);
+  for (int i = 0; i < 100; i++) {
+    v.push_back((i % 2 == 0) ? 560 : -560);
+  }
+  return v;
+}
+
+static const std::vector<int32_t> &get_ir_timings_100() {
+  static const std::vector<int32_t> timings = make_ir_timings_100();
+  return timings;
+}
+
+static void Encode_InfraredRFReceiveEvent(benchmark::State &state) {
+  InfraredRFReceiveEvent msg;
+  msg.key = 0xDEADBEEF;
+  msg.timings = &get_ir_timings_100();
+  APIBuffer buffer;
+  buffer.resize(msg.calculate_size());
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
+    benchmark::DoNotOptimize(buffer.data());
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Encode_InfraredRFReceiveEvent);
+
+static void CalculateSize_InfraredRFReceiveEvent(benchmark::State &state) {
+  InfraredRFReceiveEvent msg;
+  msg.key = 0xDEADBEEF;
+  msg.timings = &get_ir_timings_100();
+
+  for (auto _ : state) {
+    uint32_t result = 0;
+    for (int i = 0; i < kInnerIterations; i++) {
+      result += msg.calculate_size();
+    }
+    benchmark::DoNotOptimize(result);
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(CalculateSize_InfraredRFReceiveEvent);
+
+// Hand-built wire bytes for InfraredRFTransmitRawTimingsRequest (decode-only,
+// no sister message with identical wire layout).
+//   field 2 (key, fixed32):           tag=0x15, 4 LE bytes
+//   field 3 (carrier_frequency):      tag=0x18, varint
+//   field 4 (repeat_count):           tag=0x20, varint
+//   field 5 (timings, packed sint32): tag=0x2A, length varint, packed payload
+//   field 6 (modulation):             tag=0x30, varint
+static APIBuffer build_infrared_rf_transmit_wire() {
+  uint8_t bytes[256];
+  size_t len = 0;
+
+  auto put_byte = [&](uint8_t b) { bytes[len++] = b; };
+  auto put_varint = [&](uint32_t v) {
+    while (v >= 0x80) {
+      bytes[len++] = static_cast<uint8_t>((v & 0x7F) | 0x80);
+      v >>= 7;
+    }
+    bytes[len++] = static_cast<uint8_t>(v);
+  };
+  auto encode_zigzag = [](int32_t v) -> uint32_t {
+    return (static_cast<uint32_t>(v) << 1) ^ static_cast<uint32_t>(v >> 31);
+  };
+
+  put_byte(0x15);
+  put_byte(0xEF);
+  put_byte(0xBE);
+  put_byte(0xAD);
+  put_byte(0xDE);
+  put_byte(0x18);
+  put_varint(38000);
+  put_byte(0x20);
+  put_varint(2);
+
+  uint8_t packed[200];
+  size_t packed_len = 0;
+  for (int i = 0; i < 100; i++) {
+    int32_t value = (i % 2 == 0) ? 560 : -560;
+    uint32_t zz = encode_zigzag(value);
+    while (zz >= 0x80) {
+      packed[packed_len++] = static_cast<uint8_t>((zz & 0x7F) | 0x80);
+      zz >>= 7;
+    }
+    packed[packed_len++] = static_cast<uint8_t>(zz);
+  }
+  put_byte(0x2A);
+  put_varint(static_cast<uint32_t>(packed_len));
+  std::memcpy(bytes + len, packed, packed_len);
+  len += packed_len;
+  // field 6: modulation = 1 (non-zero so it's actually emitted and exercises
+  // decode_varint for this field, matching the documented layout above).
+  put_byte(0x30);
+  put_varint(1);
+
+  APIBuffer buf;
+  buf.resize(len);
+  std::memcpy(buf.data(), bytes, len);
+  return buf;
+}
+
+static void Decode_InfraredRFTransmitRawTimingsRequest(benchmark::State &state) {
+  auto encoded = build_infrared_rf_transmit_wire();
+  const uint8_t *data = encoded.data();
+  size_t size = encoded.size();
+
+  for (auto _ : state) {
+    for (int i = 0; i < kInnerIterations; i++) {
+      InfraredRFTransmitRawTimingsRequest msg;
+      msg.decode(data, size);
+      benchmark::DoNotOptimize(msg);
+    }
+  }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
+}
+BENCHMARK(Decode_InfraredRFTransmitRawTimingsRequest);
+
+#endif  // USE_IR_RF || USE_RADIO_FREQUENCY
+
+}  // namespace esphome::api::benchmarks
diff --git a/tests/benchmarks/stubs/esphome/components/infrared/infrared.h b/tests/benchmarks/stubs/esphome/components/infrared/infrared.h
new file mode 100644
index 0000000000..874e7a270b
--- /dev/null
+++ b/tests/benchmarks/stubs/esphome/components/infrared/infrared.h
@@ -0,0 +1,45 @@
+// Stub for benchmark builds — provides the minimal interface that
+// api_connection.cpp and Application need when USE_INFRARED is defined,
+// without pulling in the real remote_base/RMT dependencies.
+#pragma once
+
+#include <cstdint>
+#include "esphome/core/component.h"
+#include "esphome/core/entity_base.h"
+
+namespace esphome::infrared {
+
+class Infrared;
+
+class InfraredCall {
+ public:
+  explicit InfraredCall(Infrared *parent) : parent_(parent) {}
+  InfraredCall &set_carrier_frequency(uint32_t /*frequency*/) { return *this; }
+  InfraredCall &set_raw_timings_packed(const uint8_t * /*data*/, uint16_t /*length*/, uint16_t /*count*/) {
+    return *this;
+  }
+  InfraredCall &set_repeat_count(uint32_t /*count*/) { return *this; }
+  void perform() {}
+
+ protected:
+  Infrared *parent_;
+};
+
+class InfraredTraits {
+ public:
+  uint32_t get_receiver_frequency_hz() const { return 0; }
+};
+
+class Infrared : public Component, public EntityBase {
+ public:
+  Infrared() = default;
+  InfraredTraits &get_traits() { return this->traits_; }
+  const InfraredTraits &get_traits() const { return this->traits_; }
+  InfraredCall make_call() { return InfraredCall(this); }
+  uint32_t get_capability_flags() const { return 0; }
+
+ protected:
+  InfraredTraits traits_;
+};
+
+}  // namespace esphome::infrared
diff --git a/tests/benchmarks/stubs/esphome/components/radio_frequency/radio_frequency.h b/tests/benchmarks/stubs/esphome/components/radio_frequency/radio_frequency.h
new file mode 100644
index 0000000000..72fc08034b
--- /dev/null
+++ b/tests/benchmarks/stubs/esphome/components/radio_frequency/radio_frequency.h
@@ -0,0 +1,51 @@
+// Stub for benchmark builds — provides the minimal interface that
+// api_connection.cpp and Application need when USE_RADIO_FREQUENCY is defined.
+#pragma once
+
+#include <cstdint>
+#include "esphome/core/component.h"
+#include "esphome/core/entity_base.h"
+
+namespace esphome::radio_frequency {
+
+enum RadioFrequencyModulation : uint32_t {
+  RADIO_FREQUENCY_MODULATION_OOK = 0,
+};
+
+class RadioFrequency;
+
+class RadioFrequencyCall {
+ public:
+  explicit RadioFrequencyCall(RadioFrequency *parent) : parent_(parent) {}
+  RadioFrequencyCall &set_frequency(uint32_t /*frequency*/) { return *this; }
+  RadioFrequencyCall &set_modulation(RadioFrequencyModulation /*mod*/) { return *this; }
+  RadioFrequencyCall &set_repeat_count(uint32_t /*count*/) { return *this; }
+  RadioFrequencyCall &set_raw_timings_packed(const uint8_t * /*data*/, uint16_t /*length*/, uint16_t /*count*/) {
+    return *this;
+  }
+  void perform() {}
+
+ protected:
+  RadioFrequency *parent_;
+};
+
+class RadioFrequencyTraits {
+ public:
+  uint32_t get_frequency_min_hz() const { return 0; }
+  uint32_t get_frequency_max_hz() const { return 0; }
+  uint32_t get_supported_modulations() const { return 0; }
+};
+
+class RadioFrequency : public Component, public EntityBase {
+ public:
+  RadioFrequency() = default;
+  RadioFrequencyTraits &get_traits() { return this->traits_; }
+  const RadioFrequencyTraits &get_traits() const { return this->traits_; }
+  RadioFrequencyCall make_call() { return RadioFrequencyCall(this); }
+  uint32_t get_capability_flags() const { return 0; }
+
+ protected:
+  RadioFrequencyTraits traits_;
+};
+
+}  // namespace esphome::radio_frequency
diff --git a/tests/benchmarks/stubs/esphome/components/serial_proxy/serial_proxy.h b/tests/benchmarks/stubs/esphome/components/serial_proxy/serial_proxy.h
new file mode 100644
index 0000000000..bab27549e7
--- /dev/null
+++ b/tests/benchmarks/stubs/esphome/components/serial_proxy/serial_proxy.h
@@ -0,0 +1,46 @@
+// Stub for benchmark builds — provides the minimal interface that
+// api_connection.cpp and Application need when USE_SERIAL_PROXY is defined,
+// without pulling in the real UART implementation.
+#pragma once
+
+#include <cstdint>
+#include <cstddef>
+#include "esphome/components/api/api_pb2.h"
+
+namespace esphome {
+
+namespace api {
+class APIConnection;
+}  // namespace api
+
+namespace uart {
+enum class UARTFlushResult : uint8_t {
+  UART_FLUSH_RESULT_SUCCESS,
+  UART_FLUSH_RESULT_ASSUMED_SUCCESS,
+  UART_FLUSH_RESULT_TIMEOUT,
+  UART_FLUSH_RESULT_FAILED,
+};
+}  // namespace uart
+
+namespace serial_proxy {
+
+class SerialProxy {
+ public:
+  void set_instance_index(uint32_t index) { this->instance_index_ = index; }
+  uint32_t get_instance_index() const { return this->instance_index_; }
+  const char *get_name() const { return ""; }
+  api::enums::SerialProxyPortType get_port_type() const { return {}; }
+  api::APIConnection *get_api_connection() { return nullptr; }
+  void serial_proxy_request(api::APIConnection *conn, api::enums::SerialProxyRequestType type) {}
+  void configure(uint32_t baudrate, bool flow_control, uint8_t parity, uint32_t stop_bits, uint32_t data_size) {}
+  void write_from_client(const uint8_t *data, size_t len) {}
+  void set_modem_pins(uint32_t line_states) {}
+  uint32_t get_modem_pins() const { return 0; }
+  uart::UARTFlushResult flush_port() { return uart::UARTFlushResult::UART_FLUSH_RESULT_SUCCESS; }
+
+ protected:
+  uint32_t instance_index_{0};
+};
+
+}  // namespace serial_proxy
+}  // namespace esphome
diff --git a/tests/benchmarks/stubs/esphome/components/zwave_proxy/zwave_proxy.h b/tests/benchmarks/stubs/esphome/components/zwave_proxy/zwave_proxy.h
new file mode 100644
index 0000000000..ba97e81236
--- /dev/null
+++ b/tests/benchmarks/stubs/esphome/components/zwave_proxy/zwave_proxy.h
@@ -0,0 +1,29 @@
+// Stub for benchmark builds — provides the minimal interface that
+// api_connection.cpp needs when USE_ZWAVE_PROXY is defined,
+// without pulling in the real UART-based ZWaveProxy implementation.
+#pragma once
+
+#include "esphome/components/api/api_pb2.h"
+
+namespace esphome {
+namespace api {
+class APIConnection;
+}  // namespace api
+
+namespace zwave_proxy {
+
+class ZWaveProxy {
+ public:
+  api::APIConnection *get_api_connection() { return nullptr; }
+  void zwave_proxy_request(api::APIConnection *conn, api::enums::ZWaveProxyRequestType type) {}
+  void send_frame(const uint8_t *data, size_t length) {}
+  void api_connection_authenticated(api::APIConnection *conn) {}
+  uint32_t get_feature_flags() const { return 0; }
+  uint32_t get_home_id() { return 0; }
+};
+
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+extern ZWaveProxy *global_zwave_proxy;
+
+}  // namespace zwave_proxy
+}  // namespace esphome
diff --git a/tests/component_tests/esp32/config/reproducible_build_arduino.yaml b/tests/component_tests/esp32/config/reproducible_build_arduino.yaml
new file mode 100644
index 0000000000..a5433a441d
--- /dev/null
+++ b/tests/component_tests/esp32/config/reproducible_build_arduino.yaml
@@ -0,0 +1,8 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+  variant: esp32
+  framework:
+    type: arduino
diff --git a/tests/component_tests/esp32/test_esp32.py b/tests/component_tests/esp32/test_esp32.py
index c39a4aafc8..203f484107 100644
--- a/tests/component_tests/esp32/test_esp32.py
+++ b/tests/component_tests/esp32/test_esp32.py
@@ -16,6 +16,7 @@ from esphome.const import (
     CONF_ESPHOME,
     CONF_IGNORE_PIN_VALIDATION_ERROR,
     CONF_NUMBER,
+    KEY_NATIVE_IDF,
     PlatformFramework,
 )
 from esphome.core import CORE
@@ -243,3 +244,30 @@ def test_platformio_idf_enables_reproducible_build(
 
     sdkconfig = CORE.data[KEY_ESP32][KEY_SDKCONFIG_OPTIONS]
     assert sdkconfig.get("CONFIG_APP_REPRODUCIBLE_BUILD") is True
+
+
+def test_platformio_arduino_enables_reproducible_build(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """Test PlatformIO Arduino builds enable reproducible app metadata."""
+    generate_main(component_config_path("reproducible_build_arduino.yaml"))
+
+    sdkconfig = CORE.data[KEY_ESP32][KEY_SDKCONFIG_OPTIONS]
+    assert sdkconfig.get("CONFIG_APP_REPRODUCIBLE_BUILD") is True
+
+
+def test_native_idf_enables_reproducible_build(
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """Test native ESP-IDF builds enable reproducible app metadata."""
+    from esphome.__main__ import generate_cpp_contents
+    from esphome.config import read_config
+
+    CORE.config_path = component_config_path("reproducible_build.yaml")
+    CORE.config = read_config({})
+    CORE.data[KEY_NATIVE_IDF] = True
+    generate_cpp_contents(CORE.config)
+
+    sdkconfig = CORE.data[KEY_ESP32][KEY_SDKCONFIG_OPTIONS]
+    assert sdkconfig.get("CONFIG_APP_REPRODUCIBLE_BUILD") is True
diff --git a/tests/component_tests/image/test_init.py b/tests/component_tests/image/test_init.py
index 6f73888c7d..f7f60a1f4d 100644
--- a/tests/component_tests/image/test_init.py
+++ b/tests/component_tests/image/test_init.py
@@ -7,10 +7,12 @@ from pathlib import Path
 from typing import Any
 from unittest.mock import MagicMock, patch
 
+from PIL import Image as PILImage
 import pytest
 
 from esphome import config_validation as cv
 from esphome.components.image import (
+    CONF_ALPHA_CHANNEL,
     CONF_INVERT_ALPHA,
     CONF_OPAQUE,
     CONF_TRANSPARENCY,
@@ -411,3 +413,70 @@ async def test_svg_with_mm_dimensions_succeeds(
     assert 30 < height < 50, (
         f"Height should be around 39 pixels for 10mm at 100dpi, got {height}"
     )
+
+
+@pytest.mark.asyncio
+async def test_rgb565_alpha_animation_layout_per_frame(
+    tmp_path: Path,
+    mock_progmem_array: MagicMock,
+) -> None:
+    """RGB565+alpha animations must store each frame as a self-contained
+    [RGB plane | alpha plane] block. Animation::update_data_start_ steps frames
+    with a single per-frame stride, so any cross-frame layout (all RGB then all
+    alpha) makes the C++ alpha read land in the next frame's RGB bytes — that
+    was the regression behind issue #15999.
+    """
+    # Build a 2-frame APNG where each frame is a solid color with a known
+    # alpha. APNG preserves full RGBA per pixel (GIF only has 1-bit alpha so
+    # round-tripping mid-range alpha values does not work). Frame 0 is fully
+    # opaque red, frame 1 is fully transparent blue.
+    width = 4
+    height = 3
+    frame0 = PILImage.new("RGBA", (width, height), (255, 0, 0, 0xFF))
+    frame1 = PILImage.new("RGBA", (width, height), (0, 0, 255, 0x00))
+    apng_path = tmp_path / "anim.png"
+    frame0.save(
+        apng_path,
+        format="PNG",
+        save_all=True,
+        append_images=[frame1],
+        duration=100,
+        loop=0,
+    )
+
+    config = {
+        CONF_FILE: str(apng_path),
+        CONF_TYPE: "RGB565",
+        CONF_TRANSPARENCY: CONF_ALPHA_CHANNEL,
+        CONF_DITHER: "NONE",
+        CONF_INVERT_ALPHA: False,
+        CONF_RAW_DATA_ID: "test_raw_data_id",
+    }
+
+    _, _, _, _, _, frame_count = await write_image(config, all_frames=True)
+    assert frame_count == 2
+
+    # Recover the bytes handed to progmem_array. Signature is (id_, rhs).
+    _, raw_data = mock_progmem_array.call_args.args
+    data = [int(x) for x in raw_data]
+
+    rgb_size = width * height * 2
+    alpha_size = width * height
+    frame_size = rgb_size + alpha_size
+    assert len(data) == frame_size * frame_count, (
+        "RGB565+alpha animation buffer must be (RGB + alpha) per frame, not "
+        "all RGB followed by all alpha"
+    )
+
+    # Frame 0: RGB plane is red, alpha plane is 0xFF. Frame 1: alpha plane is
+    # 0x00. If the layout regresses to [all RGB | all alpha], the alpha bytes
+    # would all land at the tail of the buffer and the per-frame slices below
+    # would point at RGB565 noise instead.
+    frame0_alpha = data[rgb_size : rgb_size + alpha_size]
+    frame1_alpha = data[frame_size + rgb_size : frame_size + rgb_size + alpha_size]
+    assert all(a == 0xFF for a in frame0_alpha), (
+        f"Frame 0 alpha plane should be opaque, got {frame0_alpha}"
+    )
+    assert all(a == 0x00 for a in frame1_alpha), (
+        f"Frame 1 alpha plane should be transparent, got {frame1_alpha}"
+    )
diff --git a/tests/component_tests/lvgl/__init__.py b/tests/component_tests/lvgl/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/component_tests/lvgl/test_grid_layout.py b/tests/component_tests/lvgl/test_grid_layout.py
new file mode 100644
index 0000000000..dfd4b2460c
--- /dev/null
+++ b/tests/component_tests/lvgl/test_grid_layout.py
@@ -0,0 +1,239 @@
+"""Unit tests for the LVGL grid layout shorthand and rows/columns auto-sizing."""
+
+from __future__ import annotations
+
+import pytest
+from voluptuous import Invalid
+
+from esphome.components.lvgl.defines import (
+    CONF_GRID_COLUMNS,
+    CONF_GRID_ROWS,
+    CONF_LAYOUT,
+    CONF_WIDGETS,
+    TYPE_GRID,
+)
+from esphome.components.lvgl.layout import GridLayout, grid_dimension
+from esphome.const import CONF_TYPE
+
+FR1 = "LV_GRID_FR(1)"
+
+
+def _widgets(n: int) -> list[dict]:
+    """Build a list of `n` placeholder widgets for the validate() input."""
+    return [{"label": {}} for _ in range(n)]
+
+
+# ---------------------------------------------------------------------------
+# grid_dimension validator
+# ---------------------------------------------------------------------------
+
+
+def test_grid_dimension_int_expands_to_fr1_list() -> None:
+    """A positive integer should expand to a list of LV_GRID_FR(1) entries."""
+    assert grid_dimension(1) == [FR1]
+    assert grid_dimension(3) == [FR1, FR1, FR1]
+
+
+def test_grid_dimension_zero_or_negative_rejected() -> None:
+    """Non-positive integers must be rejected."""
+    with pytest.raises(Invalid):
+        grid_dimension(0)
+    with pytest.raises(Invalid):
+        grid_dimension(-2)
+
+
+def test_grid_dimension_list_passes_through() -> None:
+    """A list should be validated through the existing grid_spec list schema."""
+    result = grid_dimension(["100px", "content", "fr(2)"])
+    # `grid_spec` normalises each entry: pixel sizes become ints, the
+    # CONTENT keyword is uppercased and prefixed, and FR(n) is normalised.
+    assert result == [100, "LV_GRID_CONTENT", "LV_GRID_FR(2)"]
+
+
+def test_grid_dimension_invalid_string_rejected() -> None:
+    """A string is not a valid grid dimension and should be rejected."""
+    with pytest.raises(Invalid):
+        grid_dimension("not a list")
+
+
+def test_grid_dimension_empty_list_rejected() -> None:
+    """An empty list of grid specs must be rejected."""
+    with pytest.raises(Invalid, match="at least one entry"):
+        grid_dimension([])
+
+
+# ---------------------------------------------------------------------------
+# Shorthand string layouts
+# ---------------------------------------------------------------------------
+
+
+def test_shorthand_full_form_unchanged() -> None:
+    """`<rows>x<cols>` continues to work and yields the exact dimensions."""
+    config = {CONF_LAYOUT: "2x3", CONF_WIDGETS: _widgets(0)}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    assert layout[CONF_TYPE] == TYPE_GRID
+    assert layout[CONF_GRID_ROWS] == [FR1, FR1]
+    assert layout[CONF_GRID_COLUMNS] == [FR1, FR1, FR1]
+
+
+def test_shorthand_rows_only_calculates_columns_from_widgets() -> None:
+    """`<rows>x` derives the column count from the number of widgets."""
+    config = {CONF_LAYOUT: "3x", CONF_WIDGETS: _widgets(7)}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    # 7 widgets / 3 rows -> ceil = 3 columns.
+    assert len(layout[CONF_GRID_ROWS]) == 3
+    assert len(layout[CONF_GRID_COLUMNS]) == 3
+
+
+def test_shorthand_columns_only_calculates_rows_from_widgets() -> None:
+    """`x<cols>` derives the row count from the number of widgets."""
+    config = {CONF_LAYOUT: "x4", CONF_WIDGETS: _widgets(5)}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    # 5 widgets / 4 cols -> ceil = 2 rows.
+    assert len(layout[CONF_GRID_ROWS]) == 2
+    assert len(layout[CONF_GRID_COLUMNS]) == 4
+
+
+def test_shorthand_rows_only_no_widgets_defaults_columns_to_one() -> None:
+    """With no widgets and only rows specified, the column count defaults to 1."""
+    config = {CONF_LAYOUT: "3x", CONF_WIDGETS: []}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    assert len(layout[CONF_GRID_ROWS]) == 3
+    assert len(layout[CONF_GRID_COLUMNS]) == 1
+
+
+def test_shorthand_columns_only_no_widgets_defaults_rows_to_one() -> None:
+    """With no widgets and only columns specified, the row count defaults to 1."""
+    config = {CONF_LAYOUT: "x4", CONF_WIDGETS: []}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    assert len(layout[CONF_GRID_ROWS]) == 1
+    assert len(layout[CONF_GRID_COLUMNS]) == 4
+
+
+def test_shorthand_with_whitespace_accepted() -> None:
+    """The shorthand parser should tolerate whitespace around the components."""
+    config = {CONF_LAYOUT: "  3 x ", CONF_WIDGETS: _widgets(6)}
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    # 6 widgets / 3 rows -> 2 columns.
+    assert len(layout[CONF_GRID_ROWS]) == 3
+    assert len(layout[CONF_GRID_COLUMNS]) == 2
+
+
+def test_shorthand_bare_x_rejected() -> None:
+    """Pure `x` (no digits at all) is not a valid shorthand."""
+    config = {CONF_LAYOUT: "x", CONF_WIDGETS: _widgets(2)}
+    with pytest.raises(Invalid):
+        GridLayout().validate(config)
+
+
+@pytest.mark.parametrize(
+    "layout,bad_label",
+    [
+        ("0x3", "row"),
+        ("3x0", "column"),
+        ("0x", "row"),
+        ("x0", "column"),
+        ("0x0", "row"),
+    ],
+)
+def test_shorthand_zero_dimension_rejected(layout: str, bad_label: str) -> None:
+    """Shorthand row/column counts must be >= 1."""
+    config = {CONF_LAYOUT: layout, CONF_WIDGETS: _widgets(2)}
+    with pytest.raises(Invalid, match=f"{bad_label} count must be at least 1"):
+        GridLayout().validate(config)
+
+
+def test_shorthand_get_layout_schemas_recognizes_partial_forms() -> None:
+    """`<rows>x` and `x<cols>` should be picked up by GridLayout.get_layout_schemas."""
+    grid = GridLayout()
+    for layout in ("3x", "x4", "2x3"):
+        layout_schema, _ = grid.get_layout_schemas({CONF_LAYOUT: layout})
+        assert layout_schema is not None, f"{layout!r} should be recognised"
+    # Pure `x` and unrelated strings should not be picked up as a grid layout.
+    for layout in ("x", "horizontal"):
+        layout_schema, _ = grid.get_layout_schemas({CONF_LAYOUT: layout})
+        assert layout_schema is None, f"{layout!r} should not be recognised"
+
+
+# ---------------------------------------------------------------------------
+# Dict-form layouts with rows/columns auto-sizing
+# ---------------------------------------------------------------------------
+
+
+def test_dict_rows_only_calculates_columns_from_widgets() -> None:
+    """A dict layout with only rows fills in the column count from widget count."""
+    config = {
+        CONF_LAYOUT: {
+            CONF_TYPE: TYPE_GRID,
+            CONF_GRID_ROWS: [FR1, FR1],
+        },
+        CONF_WIDGETS: _widgets(5),
+    }
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    # 5 widgets / 2 rows -> ceil = 3 columns.
+    assert len(layout[CONF_GRID_ROWS]) == 2
+    assert layout[CONF_GRID_COLUMNS] == [FR1, FR1, FR1]
+
+
+def test_dict_columns_only_calculates_rows_from_widgets() -> None:
+    """A dict layout with only columns fills in the row count from widget count."""
+    config = {
+        CONF_LAYOUT: {
+            CONF_TYPE: TYPE_GRID,
+            CONF_GRID_COLUMNS: [FR1, FR1, FR1],
+        },
+        CONF_WIDGETS: _widgets(7),
+    }
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    # 7 widgets / 3 cols -> ceil = 3 rows.
+    assert layout[CONF_GRID_ROWS] == [FR1, FR1, FR1]
+    assert len(layout[CONF_GRID_COLUMNS]) == 3
+
+
+def test_dict_rows_only_no_widgets_defaults_columns_to_one() -> None:
+    """A dict layout with rows but no widgets defaults columns to 1."""
+    config = {
+        CONF_LAYOUT: {
+            CONF_TYPE: TYPE_GRID,
+            CONF_GRID_ROWS: [FR1, FR1, FR1],
+        },
+        CONF_WIDGETS: [],
+    }
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    assert len(layout[CONF_GRID_ROWS]) == 3
+    assert layout[CONF_GRID_COLUMNS] == [FR1]
+
+
+def test_dict_neither_rows_nor_columns_rejected() -> None:
+    """A grid layout dict without rows AND without columns must be rejected."""
+    config = {
+        CONF_LAYOUT: {CONF_TYPE: TYPE_GRID},
+        CONF_WIDGETS: _widgets(3),
+    }
+    with pytest.raises(Invalid):
+        GridLayout().validate(config)
+
+
+def test_dict_both_rows_and_columns_unchanged() -> None:
+    """When both dimensions are present they are preserved as-is."""
+    config = {
+        CONF_LAYOUT: {
+            CONF_TYPE: TYPE_GRID,
+            CONF_GRID_ROWS: [FR1, FR1],
+            CONF_GRID_COLUMNS: [FR1, FR1, FR1],
+        },
+        CONF_WIDGETS: _widgets(0),
+    }
+    result = GridLayout().validate(config)
+    layout = result[CONF_LAYOUT]
+    assert layout[CONF_GRID_ROWS] == [FR1, FR1]
+    assert layout[CONF_GRID_COLUMNS] == [FR1, FR1, FR1]
diff --git a/tests/components/api/common-base.yaml b/tests/components/api/common-base.yaml
index c766b61b13..504c52a57b 100644
--- a/tests/components/api/common-base.yaml
+++ b/tests/components/api/common-base.yaml
@@ -91,6 +91,24 @@ api:
               - float_arr.size()
               - string_arr[0].c_str()
               - string_arr.size()
+    # Test array + string args used after a non-synchronous action (delay).
+    # The default non-owning types (StringRef, const FixedVector&) would
+    # dangle once rx_buf_ is reused, and FixedVector is non-copyable so
+    # DelayAction's lambda capture would fail to compile.  The api codegen
+    # must fall back to owning std::string / std::vector here.
+    - action: array_with_delay
+      variables:
+        name: string
+        int_arr: int[]
+        string_arr: string[]
+      then:
+        - delay: 20ms
+        - logger.log:
+            format: "Delayed: %s (%u ints, %u strings)"
+            args:
+              - name.c_str()
+              - int_arr.size()
+              - string_arr.size()
     # Test ContinuationAction (IfAction with then/else branches)
     - action: test_if_action
       variables:
diff --git a/tests/components/api/test_proto_mac_varint.cpp b/tests/components/api/test_proto_mac_varint.cpp
new file mode 100644
index 0000000000..f2a63e96f6
--- /dev/null
+++ b/tests/components/api/test_proto_mac_varint.cpp
@@ -0,0 +1,123 @@
+#include <gtest/gtest.h>
+
+#include <cstdint>
+#include <ios>
+#include <random>
+
+#include "esphome/components/api/api_buffer.h"
+#include "esphome/components/api/proto.h"
+
+namespace esphome::api::testing {
+
+// Generic varint decoder, used to verify the encoded bytes round-trip back to
+// the original 48-bit MAC value, independent of the specialized encoder under
+// test.
+static uint64_t decode_varint(const uint8_t *buf, size_t len, size_t *consumed) {
+  uint64_t value = 0;
+  int shift = 0;
+  for (size_t i = 0; i < len; i++) {
+    value |= static_cast<uint64_t>(buf[i] & 0x7F) << shift;
+    if ((buf[i] & 0x80) == 0) {
+      *consumed = i + 1;
+      return value;
+    }
+    shift += 7;
+  }
+  *consumed = 0;
+  return 0;
+}
+
+// Reference encoder mirroring ProtoEncode::encode_varint_raw_64.
+static size_t reference_encode(uint64_t value, uint8_t *out) {
+  uint8_t *p = out;
+  if (value < 128) {
+    *p++ = static_cast<uint8_t>(value);
+    return p - out;
+  }
+  do {
+    *p++ = static_cast<uint8_t>(value | 0x80);
+    value >>= 7;
+  } while (value > 0x7F);
+  *p++ = static_cast<uint8_t>(value);
+  return p - out;
+}
+
+// Encode `mac` via the 48-bit fast path and verify:
+//  - byte-identical output to the reference loop
+//  - encoded byte length matches `expected_bytes`
+//  - calc_uint64_48bit_force agrees on the size
+//  - the bytes round-trip through a generic varint decoder
+static void verify_mac(uint64_t mac, size_t expected_bytes) {
+  ASSERT_LT(mac, 1ULL << 48) << "test fixture mac exceeds 48 bits";
+
+  uint8_t ref_buf[16] = {0};
+  size_t ref_len = reference_encode(mac, ref_buf);
+
+  APIBuffer api_buf;
+  api_buf.resize(16);
+  uint8_t *pos = api_buf.data();
+#ifdef ESPHOME_DEBUG_API
+  uint8_t *proto_debug_end_ = api_buf.data() + api_buf.size();
+#endif
+  ProtoEncode::encode_varint_raw_48bit(pos PROTO_ENCODE_DEBUG_ARG, mac);
+  size_t new_len = pos - api_buf.data();
+
+  EXPECT_EQ(new_len, expected_bytes) << "mac=0x" << std::hex << mac << std::dec;
+  EXPECT_EQ(ref_len, expected_bytes) << "reference disagrees on length for mac=0x" << std::hex << mac << std::dec;
+
+  for (size_t i = 0; i < new_len; i++) {
+    EXPECT_EQ(api_buf.data()[i], ref_buf[i])
+        << "byte " << i << " differs for mac=0x" << std::hex << mac << " (got 0x" << static_cast<int>(api_buf.data()[i])
+        << ", expected 0x" << static_cast<int>(ref_buf[i]) << ")" << std::dec;
+  }
+
+  size_t consumed = 0;
+  uint64_t decoded = decode_varint(api_buf.data(), new_len, &consumed);
+  EXPECT_EQ(consumed, new_len) << "decoder did not consume all bytes for mac=0x" << std::hex << mac << std::dec;
+  EXPECT_EQ(decoded, mac) << "round-trip mismatch for mac=0x" << std::hex << mac << std::dec;
+
+  // Verify the size helper agrees. field_id_size = 1 (typical 1-byte tag).
+  uint32_t calc_size = ProtoSize::calc_uint64_48bit_force(1, mac);
+  EXPECT_EQ(calc_size, 1 + expected_bytes)
+      << "calc_uint64_48bit_force size mismatch for mac=0x" << std::hex << mac << std::dec;
+}
+
+// Compute the canonical varint byte length for a value < 1<<48.
+static size_t expected_varint_len(uint64_t v) {
+  if (v < (1ULL << 7))
+    return 1;
+  if (v < (1ULL << 14))
+    return 2;
+  if (v < (1ULL << 21))
+    return 3;
+  if (v < (1ULL << 28))
+    return 4;
+  if (v < (1ULL << 35))
+    return 5;
+  if (v < (1ULL << 42))
+    return 6;
+  return 7;
+}
+
+// --- Specific MACs requested for verification ---
+
+TEST(ProtoMacVarint, AllZeros) { verify_mac(0x000000000000ULL, 1); }        // 00:00:00:00:00:00
+TEST(ProtoMacVarint, FirstByteOnly) { verify_mac(0x110000000000ULL, 7); }   // 11:00:00:00:00:00
+TEST(ProtoMacVarint, SecondByteOnly) { verify_mac(0x00AA00000000ULL, 6); }  // 00:AA:00:00:00:00
+TEST(ProtoMacVarint, ThirdByteOnly) { verify_mac(0x0000BB000000ULL, 5); }   // 00:00:BB:00:00:00
+TEST(ProtoMacVarint, FourthByteOnly) { verify_mac(0x000000CC0000ULL, 4); }  // 00:00:00:CC:00:00
+TEST(ProtoMacVarint, FifthByteOnly) { verify_mac(0x00000000DD00ULL, 3); }   // 00:00:00:00:DD:00
+TEST(ProtoMacVarint, SixthByteOnly) { verify_mac(0x0000000000EEULL, 2); }   // 00:00:00:00:00:EE
+TEST(ProtoMacVarint, AllOnes) { verify_mac(0xFFFFFFFFFFFFULL, 7); }         // FF:FF:FF:FF:FF:FF
+
+// 100 deterministic-random 48-bit MACs to catch regressions across the space.
+TEST(ProtoMacVarint, RandomSample) {
+  // NOLINTNEXTLINE(cert-msc32-c,cert-msc51-cpp,bugprone-random-generator-seed) -- fixed seed for reproducibility
+  std::mt19937_64 rng(0xC0FFEE);
+  for (int i = 0; i < 100; i++) {
+    uint64_t mac = rng() & 0xFFFFFFFFFFFFULL;
+    verify_mac(mac, expected_varint_len(mac));
+  }
+}
+
+}  // namespace esphome::api::testing
diff --git a/tests/components/audio/common.yaml b/tests/components/audio/common.yaml
new file mode 100644
index 0000000000..3cde9b8449
--- /dev/null
+++ b/tests/components/audio/common.yaml
@@ -0,0 +1,14 @@
+audio:
+  codecs:
+    flac:
+      buffer_memory: internal
+    mp3:
+      buffer_memory: psram
+    opus:
+      floating_point: false
+      state_memory: psram
+      pseudostack:
+        threadsafe: false
+        buffer_memory: internal
+        size: 80000
+    wav:
diff --git a/tests/components/audio/test.esp32-idf.yaml b/tests/components/audio/test.esp32-idf.yaml
new file mode 100644
index 0000000000..dade44d145
--- /dev/null
+++ b/tests/components/audio/test.esp32-idf.yaml
@@ -0,0 +1 @@
+<<: !include common.yaml
diff --git a/tests/components/climate/common.yaml b/tests/components/climate/common.yaml
index ff405b68e2..c28fde8eeb 100644
--- a/tests/components/climate/common.yaml
+++ b/tests/components/climate/common.yaml
@@ -29,3 +29,74 @@ climate:
     heat_action:
       - switch.turn_on: climate_heater_switch
       - switch.turn_off: climate_cooler_switch
+  # Thermostat-based climate so climate.control: action variants get build
+  # coverage (bang_bang doesn't support fan modes, presets, etc.). Climate
+  # has no template platform, so thermostat is the right vehicle.
+  - platform: thermostat
+    id: climate_test_thermostat
+    name: Test Thermostat
+    sensor: climate_temperature_sensor
+    min_idle_time: 30s
+    min_heating_off_time: 300s
+    min_heating_run_time: 300s
+    min_cooling_off_time: 300s
+    min_cooling_run_time: 300s
+    heat_action:
+      - logger.log: heating
+    idle_action:
+      - logger.log: idle
+    cool_action:
+      - logger.log: cooling
+    auto_mode:
+      - logger.log: auto
+    heat_cool_mode:
+      - logger.log: heat_cool
+    preset:
+      - name: Default
+        default_target_temperature_low: 18°C
+        default_target_temperature_high: 22°C
+
+button:
+  # Exercise the climate.control: action so ControlAction templates get
+  # build coverage. Various field combinations are tested.
+  - platform: template
+    name: "Climate Control Mode"
+    on_press:
+      - climate.control:
+          id: climate_test_thermostat
+          mode: HEAT
+  - platform: template
+    name: "Climate Control Mode And Temps"
+    on_press:
+      - climate.control:
+          id: climate_test_thermostat
+          mode: HEAT_COOL
+          target_temperature_low: 19.0°C
+          target_temperature_high: 23.0°C
+  - platform: template
+    name: "Climate Control Lambda Temp"
+    on_press:
+      - climate.control:
+          id: climate_test_thermostat
+          target_temperature_high: !lambda "return 21.5;"
+  - platform: template
+    name: "Climate Control Off"
+    on_press:
+      - climate.control:
+          id: climate_test_thermostat
+          mode: "OFF"
+
+# Exercise climate.control inside a trigger with non-empty Ts (number on_value
+# passes float).
+number:
+  - platform: template
+    id: climate_target_temp_number
+    optimistic: true
+    min_value: 16
+    max_value: 28
+    step: 0.5
+    on_value:
+      then:
+        - climate.control:
+            id: climate_test_thermostat
+            target_temperature_high: !lambda "return x;"
diff --git a/tests/components/fan/common.yaml b/tests/components/fan/common.yaml
index 099bbfef08..76508f391e 100644
--- a/tests/components/fan/common.yaml
+++ b/tests/components/fan/common.yaml
@@ -9,6 +9,14 @@ fan:
     has_oscillating: true
     has_direction: true
     speed_count: 3
+    # Exercise fan.turn_on inside a trigger whose Ts pack is non-empty
+    # (StringRef from on_preset_set) so the apply-lambda + inner-lambda
+    # codegen runs through the cvref-normalized path.
+    on_preset_set:
+      then:
+        - fan.turn_on:
+            id: test_fan
+            speed: !lambda "return x.empty() ? 1 : 3;"
 
 # Test lambdas using get_preset_mode() which returns StringRef
 # These examples match the migration guide in the PR description
@@ -57,3 +65,52 @@ binary_sensor:
         return true;
       }
       return false;
+
+# Exercise fan.turn_on with various field combinations so the
+# TurnOnAction codegen paths get build coverage.
+button:
+  - platform: template
+    name: "Fan Speed Only"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          speed: 2
+  - platform: template
+    name: "Fan Oscillating + Direction"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          oscillating: true
+          direction: REVERSE
+  - platform: template
+    name: "Fan All Fields"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          oscillating: false
+          speed: 3
+          direction: FORWARD
+  - platform: template
+    name: "Fan Lambda Speed"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          speed: !lambda 'return 1;'
+
+# Exercise fan.turn_on inside triggers with non-empty Ts:
+#  - number.on_value: Ts = float (Python value type; previously raised
+#    AttributeError on .operator("const"))
+#  - fan.on_preset_set: Ts = StringRef (already a value-type wrapper around
+#    a const char * + size; tests the cvref-normalized inner-lambda path)
+number:
+  - platform: template
+    id: fan_speed_number
+    optimistic: true
+    min_value: 1
+    max_value: 3
+    step: 1
+    on_value:
+      then:
+        - fan.turn_on:
+            id: test_fan
+            speed: !lambda "return (int) x;"
diff --git a/tests/components/json/__init__.py b/tests/components/json/__init__.py
new file mode 100644
index 0000000000..40ec1f996e
--- /dev/null
+++ b/tests/components/json/__init__.py
@@ -0,0 +1,9 @@
+from tests.testing_helpers import ComponentManifestOverride
+
+
+def override_manifest(manifest: ComponentManifestOverride) -> None:
+    # json's to_code calls cg.add_library("bblanchon/ArduinoJson", ...). C++
+    # unit test builds that pull json in transitively (e.g. api) need that
+    # library registration to happen, otherwise json_util.cpp fails to find
+    # ArduinoJson.h.
+    manifest.enable_codegen()
diff --git a/tests/components/light/common.yaml b/tests/components/light/common.yaml
index e1216e7b60..044a8144fa 100644
--- a/tests/components/light/common.yaml
+++ b/tests/components/light/common.yaml
@@ -108,6 +108,10 @@ esphome:
           relative_brightness: 5%
           brightness_limits:
             max_brightness: 90%
+      - light.dim_relative:
+          id: test_monochromatic_light
+          relative_brightness: -5%
+          transition_length: 250ms
       - light.turn_on:
           id: test_addressable_transition
           brightness: 50%
@@ -123,6 +127,21 @@ esphome:
           blue: 0%
           transition_length: 1s
 
+# Exercise light actions inside a trigger with non-empty Ts (number on_value
+# passes float).
+number:
+  - platform: template
+    id: test_number_brightness
+    optimistic: true
+    min_value: 0
+    max_value: 100
+    step: 1
+    on_value:
+      then:
+        - light.turn_on:
+            id: test_monochromatic_light
+            brightness: !lambda "return x / 100.0;"
+
 light:
   - platform: binary
     id: test_binary_light
diff --git a/tests/components/lvgl/lvgl-package.yaml b/tests/components/lvgl/lvgl-package.yaml
index d3565c6c59..9c4ad4bbf8 100644
--- a/tests/components/lvgl/lvgl-package.yaml
+++ b/tests/components/lvgl/lvgl-package.yaml
@@ -16,10 +16,19 @@ binary_sensor:
     platform: template
   - id: left_sensor
     platform: template
+  - platform: lvgl
+    name: Button A pressed
+    widget: button_a
+    state: pressed
+  - platform: lvgl
+    name: Button A checked
+    widget: button_a
+    state: checked
   - platform: lvgl
     id: button_checker
     name: LVGL button
     widget: button_button
+    state: checked
     on_state:
       then:
         - lvgl.checkbox.update:
@@ -29,6 +38,12 @@ binary_sensor:
                   auto y = x; // block inlining of one line return
                   return y;
 
+  - platform: lvgl
+    id: button_presser
+    name: Button pressed
+    widget: button_button
+    state: pressed
+
 lvgl:
   id: lvgl_id
   rotation: 90
@@ -1098,6 +1113,8 @@ lvgl:
                   pad_row: 6px
                   pad_column: 0
                   multiple_widgets_per_cell: true
+                  grid_cell_x_align: center
+                  grid_cell_y_align: center
                 widgets:
                   - image:
                       grid_cell_row_pos: 0
@@ -1290,6 +1307,87 @@ lvgl:
                 hidden: true
                 mode: text_lower
 
+        # Grid shorthand "<rows>x": 3 rows specified, columns derived
+        # from widget count (4 widgets / 3 rows -> 2 columns)
+        - obj:
+            id: grid_rows_only_shorthand
+            layout: 3x
+            widgets:
+              - label:
+                  text: "r1"
+              - label:
+                  text: "r2"
+              - label:
+                  text: "r3"
+              - label:
+                  text: "r4"
+
+        # Grid shorthand "x<cols>": 4 columns specified, rows derived
+        # from widget count (5 widgets / 4 cols -> 2 rows)
+        - obj:
+            id: grid_cols_only_shorthand
+            layout: x4
+            widgets:
+              - label:
+                  text: "a"
+              - label:
+                  text: "b"
+              - label:
+                  text: "c"
+              - label:
+                  text: "d"
+              - label:
+                  text: "e"
+
+        # Grid dict form with grid_rows as a plain integer; columns derived
+        - obj:
+            id: grid_rows_int
+            layout:
+              type: grid
+              grid_rows: 2
+            widgets:
+              - label:
+                  text: "1"
+              - label:
+                  text: "2"
+              - label:
+                  text: "3"
+
+        # Grid dict form with grid_columns as a plain integer; rows derived
+        - obj:
+            id: grid_cols_int
+            layout:
+              type: grid
+              grid_columns: 3
+            widgets:
+              - label:
+                  text: "x"
+              - label:
+                  text: "y"
+              - label:
+                  text: "z"
+              - label:
+                  text: "w"
+              - label:
+                  text: "v"
+
+        # Grid dict form with both grid_rows and grid_columns as plain integers
+        - obj:
+            id: grid_both_int
+            layout:
+              type: grid
+              grid_rows: 2
+              grid_columns: 2
+            widgets:
+              - label:
+                  text: "1,1"
+              - label:
+                  text: "1,2"
+              - label:
+                  text: "2,1"
+              - label:
+                  text: "2,2"
+
 font:
   - file: "gfonts://Roboto"
     id: space16
diff --git a/tests/components/mapping/common.yaml b/tests/components/mapping/common.yaml
index 7ffcfa4f67..b3db9d54eb 100644
--- a/tests/components/mapping/common.yaml
+++ b/tests/components/mapping/common.yaml
@@ -21,6 +21,7 @@ mapping:
     entries:
       clear-night: image_1
       sunny: image_2
+    default_value: image_1
   - id: weather_map_2
     from: string
     to: image
@@ -35,6 +36,7 @@ mapping:
       2: "two"
       3: "three"
       77: "seventy-seven"
+    default_value: unknown
   - id: string_map
     from: string
     to: int
diff --git a/tests/components/mapping/test.esp32-idf.yaml b/tests/components/mapping/test.esp32-idf.yaml
index a35b6940c7..93adcf9988 100644
--- a/tests/components/mapping/test.esp32-idf.yaml
+++ b/tests/components/mapping/test.esp32-idf.yaml
@@ -4,7 +4,7 @@ packages:
 
 display:
   spi_id: spi_bus
-  platform: ili9xxx
+  platform: mipi_spi
   id: main_lcd
   model: ili9342
   cs_pin: 12
diff --git a/tests/components/mapping/test.esp8266-ard.yaml b/tests/components/mapping/test.esp8266-ard.yaml
index c59821a211..6a308b67dd 100644
--- a/tests/components/mapping/test.esp8266-ard.yaml
+++ b/tests/components/mapping/test.esp8266-ard.yaml
@@ -4,7 +4,7 @@ packages:
 
 display:
   spi_id: spi_bus
-  platform: ili9xxx
+  platform: mipi_spi
   id: main_lcd
   model: ili9342
   cs_pin: 5
diff --git a/tests/components/mapping/test.rp2040-ard.yaml b/tests/components/mapping/test.rp2040-ard.yaml
index fdfed5f6ab..01b83c4ab8 100644
--- a/tests/components/mapping/test.rp2040-ard.yaml
+++ b/tests/components/mapping/test.rp2040-ard.yaml
@@ -4,7 +4,7 @@ packages:
 
 display:
   spi_id: spi_bus
-  platform: ili9xxx
+  platform: mipi_spi
   id: main_lcd
   model: ili9342
   data_rate: 31.25MHz
diff --git a/tests/components/mdns/common-enabled-ethernet.yaml b/tests/components/mdns/common-enabled-ethernet.yaml
new file mode 100644
index 0000000000..bfa9321d43
--- /dev/null
+++ b/tests/components/mdns/common-enabled-ethernet.yaml
@@ -0,0 +1,23 @@
+ethernet:
+  type: W5500
+  clk_pin: 18
+  mosi_pin: 19
+  miso_pin: 16
+  cs_pin: 17
+  interrupt_pin: 21
+  reset_pin: 20
+  manual_ip:
+    static_ip: 192.168.178.56
+    gateway: 192.168.178.1
+    subnet: 255.255.255.0
+  domain: .local
+  mac_address: "02:AA:BB:CC:DD:01"
+
+mdns:
+  disabled: false
+  services:
+    - service: _test_service
+      protocol: _tcp
+      port: 8888
+      txt:
+        static_string: Anything
diff --git a/tests/components/mdns/test-enabled-ethernet.rp2040-ard.yaml b/tests/components/mdns/test-enabled-ethernet.rp2040-ard.yaml
new file mode 100644
index 0000000000..f84a0bc276
--- /dev/null
+++ b/tests/components/mdns/test-enabled-ethernet.rp2040-ard.yaml
@@ -0,0 +1 @@
+<<: !include common-enabled-ethernet.yaml
diff --git a/tests/components/modbus_controller/common.yaml b/tests/components/modbus_controller/common.yaml
index ffaa1491c5..51951a4528 100644
--- a/tests/components/modbus_controller/common.yaml
+++ b/tests/components/modbus_controller/common.yaml
@@ -1,53 +1,11 @@
-modbus:
-  - id: mod_bus2
-    uart_id: uart_bus
-    role: server
-
 modbus_controller:
   - id: modbus_controller1
     address: 0x2
     modbus_id: modbus_bus
-    allow_duplicate_commands: false
     on_online:
       then:
         logger.log: "Module Online"
-  - id: modbus_controller2
-    address: 0x2
-    modbus_id: mod_bus2
-    server_registers:
-      - address: 0x0000
-        value_type: S_DWORD_R
-        read_lambda: |-
-          return 42.3;
-    max_cmd_retries: 0
-  - id: modbus_controller3
-    address: 0x3
-    modbus_id: mod_bus2
-    server_registers:
-      - address: 0x0009
-        value_type: S_DWORD
-        read_lambda: |-
-          return 31;
-        write_lambda: |-
-          printf("address=%d, value=%d", x);
-          return true;
-    max_cmd_retries: 0
-  - id: modbus_controller4
-    modbus_id: mod_bus2
-    address: 0x4
-    server_courtesy_response:
-      enabled: true
-      register_last_address: 100
-      register_value: 0
-    server_registers:
-      - address: 0x0001
-        value_type: U_WORD
-        read_lambda: |-
-          return 0x8;
-      - address: 0x0005
-        value_type: U_WORD
-        read_lambda: |-
-          return (random_uint32() % 100);
+
 binary_sensor:
   - platform: modbus_controller
     modbus_controller_id: modbus_controller1
diff --git a/tests/components/modbus_server/common.yaml b/tests/components/modbus_server/common.yaml
new file mode 100644
index 0000000000..3522c9248c
--- /dev/null
+++ b/tests/components/modbus_server/common.yaml
@@ -0,0 +1,41 @@
+modbus:
+  - id: mod_bus2
+    uart_id: uart_bus
+    role: server
+
+modbus_server:
+  - id: modbus_server2
+    address: 0x2
+    modbus_id: mod_bus2
+    registers:
+      - address: 0x0
+        value_type: S_DWORD_R
+        read_lambda: |-
+          return 42.3;
+  - id: modbus_server3
+    address: 0x3
+    modbus_id: mod_bus2
+    registers:
+      - address: 0x9
+        value_type: S_DWORD
+        read_lambda: |-
+          return 31;
+        write_lambda: |-
+          printf("address=%d, value=%d", x);
+          return true;
+  - id: modbus_server4
+    modbus_id: mod_bus2
+    address: 0x4
+    courtesy_response:
+      enabled: true
+      register_last_address: 100
+      register_value: 0
+    registers:
+      - address: 0x1
+        value_type: U_WORD
+        read_lambda: |-
+          return 0x8;
+      - address: 0x5
+        value_type: U_WORD
+        read_lambda: |-
+          return (random_uint32() % 100);
diff --git a/tests/components/modbus_server/test.esp32-idf.yaml b/tests/components/modbus_server/test.esp32-idf.yaml
new file mode 100644
index 0000000000..ace2d95a0b
--- /dev/null
+++ b/tests/components/modbus_server/test.esp32-idf.yaml
@@ -0,0 +1,4 @@
+packages:
+  modbus: !include ../../test_build_components/common/modbus/esp32-idf.yaml
+
+<<: !include common.yaml
diff --git a/tests/components/modbus_server/test.esp8266-ard.yaml b/tests/components/modbus_server/test.esp8266-ard.yaml
new file mode 100644
index 0000000000..560629b0cd
--- /dev/null
+++ b/tests/components/modbus_server/test.esp8266-ard.yaml
@@ -0,0 +1,4 @@
+packages:
+  modbus: !include ../../test_build_components/common/modbus/esp8266-ard.yaml
+
+<<: !include common.yaml
diff --git a/tests/components/modbus_server/test.rp2040-ard.yaml b/tests/components/modbus_server/test.rp2040-ard.yaml
new file mode 100644
index 0000000000..eeebbd2a8a
--- /dev/null
+++ b/tests/components/modbus_server/test.rp2040-ard.yaml
@@ -0,0 +1,4 @@
+packages:
+  modbus: !include ../../test_build_components/common/modbus/rp2040-ard.yaml
+
+<<: !include common.yaml
diff --git a/tests/components/nrf52/test-dfu-pin.nrf52-xiao-ble.yaml b/tests/components/nrf52/test-dfu-pin.nrf52-xiao-ble.yaml
new file mode 100644
index 0000000000..d53c692001
--- /dev/null
+++ b/tests/components/nrf52/test-dfu-pin.nrf52-xiao-ble.yaml
@@ -0,0 +1,9 @@
+nrf52:
+  dfu:
+    reset_pin:
+      number: 14
+      inverted: true
+      mode:
+        output: true
+  reg0:
+    voltage: 1.8V
diff --git a/tests/components/nrf52/test.nrf52-xiao-ble.yaml b/tests/components/nrf52/test.nrf52-xiao-ble.yaml
index d53c692001..de4c0c6e00 100644
--- a/tests/components/nrf52/test.nrf52-xiao-ble.yaml
+++ b/tests/components/nrf52/test.nrf52-xiao-ble.yaml
@@ -1,9 +1,4 @@
 nrf52:
-  dfu:
-    reset_pin:
-      number: 14
-      inverted: true
-      mode:
-        output: true
+  dfu: true
   reg0:
     voltage: 1.8V
diff --git a/tests/components/ota/test-partition_access.esp32-idf.yaml b/tests/components/ota/test-partition_access.esp32-idf.yaml
new file mode 100644
index 0000000000..0cbf854952
--- /dev/null
+++ b/tests/components/ota/test-partition_access.esp32-idf.yaml
@@ -0,0 +1,5 @@
+ota:
+  - platform: esphome
+    allow_partition_access: true
+
+<<: !include common.yaml
diff --git a/tests/components/sendspin/common-media_source.yaml b/tests/components/sendspin/common-media_source.yaml
index 4a7cd79c67..5b33a54647 100644
--- a/tests/components/sendspin/common-media_source.yaml
+++ b/tests/components/sendspin/common-media_source.yaml
@@ -7,3 +7,4 @@ media_source:
     initial_static_delay: 5ms
     static_delay_adjustable: true
     fixed_delay: 480us
+    decode_memory: internal
diff --git a/tests/components/template/common-base.yaml b/tests/components/template/common-base.yaml
index ecc65de66c..984ef129ad 100644
--- a/tests/components/template/common-base.yaml
+++ b/tests/components/template/common-base.yaml
@@ -293,6 +293,60 @@ cover:
             cover.is_closed: template_cover_with_triggers
           then:
             logger.log: Cover is closed
+  # Exercise cover.control / cover.template.publish action variants so they
+  # get build coverage in CI (and so memory-impact analysis on PRs that
+  # touch ControlAction / CoverPublishAction sees real instances).
+  - platform: template
+    name: "Template Cover Actions"
+    id: template_cover_actions
+    has_position: true
+    optimistic: true
+    open_action:
+      # CONF_STATE alias for the position bit
+      - cover.template.publish:
+          id: template_cover_actions
+          state: OPEN
+      - cover.template.publish:
+          id: template_cover_actions
+          position: 1.0
+      - cover.template.publish:
+          id: template_cover_actions
+          current_operation: IDLE
+    close_action:
+      - cover.template.publish:
+          id: template_cover_actions
+          position: 0.0
+          tilt: 0.0
+    stop_action:
+      - cover.template.publish:
+          id: template_cover_actions
+          current_operation: IDLE
+    tilt_action:
+      - lambda: |-
+          id(template_cover_actions).tilt = tilt;
+          id(template_cover_actions).publish_state();
+    on_idle:
+      # position only
+      - cover.control:
+          id: template_cover_actions
+          position: 50%
+      # tilt only
+      - cover.control:
+          id: template_cover_actions
+          tilt: 75%
+      # position + tilt
+      - cover.control:
+          id: template_cover_actions
+          position: 25%
+          tilt: 30%
+      # stop
+      - cover.control:
+          id: template_cover_actions
+          stop: true
+      # CONF_STATE alias for position
+      - cover.control:
+          id: template_cover_actions
+          state: OPEN
 
 number:
   - platform: template
@@ -302,6 +356,19 @@ number:
     min_value: 0
     max_value: 100
     step: 1
+  # Exercise valve.control inside a trigger with non-empty Ts (number on_value
+  # passes float).
+  - platform: template
+    id: template_valve_position_number
+    optimistic: true
+    min_value: 0
+    max_value: 100
+    step: 1
+    on_value:
+      then:
+        - valve.control:
+            id: template_valve
+            position: !lambda "return x / 100.0f;"
 
 select:
   - platform: template
@@ -388,6 +455,20 @@ valve:
           state: CLOSED
     stop_action:
       - logger.log: stop_action
+      # Exercise valve.control with various field combinations so the
+      # ControlAction codegen paths get build coverage.
+      - valve.control:
+          id: template_valve
+          stop: true
+      - valve.control:
+          id: template_valve
+          position: 50%
+      - valve.control:
+          id: template_valve
+          state: OPEN
+      - valve.control:
+          id: template_valve
+          position: !lambda 'return 0.25f;'
     optimistic: true
 
 text:
diff --git a/tests/components/wifi/test.esp8266-ard.yaml b/tests/components/wifi/test.esp8266-ard.yaml
index 709a639ad6..ffeec136d3 100644
--- a/tests/components/wifi/test.esp8266-ard.yaml
+++ b/tests/components/wifi/test.esp8266-ard.yaml
@@ -1,6 +1,7 @@
 wifi:
   min_auth_mode: WPA2
   post_connect_roaming: true
+  phy_mode: 11G
 
 packages:
   - !include common.yaml
diff --git a/tests/components/zephyr/common.yaml b/tests/components/zephyr/common.yaml
new file mode 100644
index 0000000000..345042df3b
--- /dev/null
+++ b/tests/components/zephyr/common.yaml
@@ -0,0 +1,8 @@
+esphome:
+  on_boot:
+    - lambda: |-
+        ESP_LOGD("test", "millis=%u micros=%u cycles=%u",
+                 (unsigned) millis(), (unsigned) micros(),
+                 (unsigned) arch_get_cpu_cycle_count());
+        delay(1);
+        delayMicroseconds(1);
diff --git a/tests/components/zephyr/test.nrf52-adafruit.yaml b/tests/components/zephyr/test.nrf52-adafruit.yaml
new file mode 100644
index 0000000000..dade44d145
--- /dev/null
+++ b/tests/components/zephyr/test.nrf52-adafruit.yaml
@@ -0,0 +1 @@
+<<: !include common.yaml
diff --git a/tests/integration/fixtures/binary_sensor_autorepeat_filter.yaml b/tests/integration/fixtures/binary_sensor_autorepeat_filter.yaml
new file mode 100644
index 0000000000..5799ece00c
--- /dev/null
+++ b/tests/integration/fixtures/binary_sensor_autorepeat_filter.yaml
@@ -0,0 +1,40 @@
+esphome:
+  name: test-autorepeat-filter
+
+host:
+api:
+  batch_delay: 0ms  # Disable batching to receive every state transition
+logger:
+  level: DEBUG
+
+binary_sensor:
+  # The autorepeat filter is applied directly to the template sensor, so each
+  # write through `binary_sensor.template.publish` runs through the filter
+  # chain. With the source true the filter must oscillate after `delay`; once
+  # the source returns to false the filter must cancel both timers and emit a
+  # final false.
+  - platform: template
+    name: "Autorepeat Sensor"
+    id: autorepeat_sensor
+    filters:
+      - autorepeat:
+          - delay: 200ms
+            time_off: 100ms
+            time_on: 100ms
+
+button:
+  - platform: template
+    name: "Press"
+    id: press_button
+    on_press:
+      - binary_sensor.template.publish:
+          id: autorepeat_sensor
+          state: true
+
+  - platform: template
+    name: "Release"
+    id: release_button
+    on_press:
+      - binary_sensor.template.publish:
+          id: autorepeat_sensor
+          state: false
diff --git a/tests/integration/fixtures/climate_control_action.yaml b/tests/integration/fixtures/climate_control_action.yaml
new file mode 100644
index 0000000000..1dd300fcc2
--- /dev/null
+++ b/tests/integration/fixtures/climate_control_action.yaml
@@ -0,0 +1,92 @@
+esphome:
+  name: climate-control-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+globals:
+  - id: test_target_temp
+    type: float
+    initial_value: "21.5"
+
+sensor:
+  - platform: template
+    id: temp_sensor
+    name: "Temp"
+    lambda: 'return 20.0;'
+    update_interval: 60s
+
+climate:
+  - platform: thermostat
+    id: test_climate
+    name: "Test Climate"
+    sensor: temp_sensor
+    min_idle_time: 30s
+    min_heating_off_time: 300s
+    min_heating_run_time: 300s
+    min_cooling_off_time: 300s
+    min_cooling_run_time: 300s
+    heat_action:
+      - logger.log: heating
+    idle_action:
+      - logger.log: idle
+    cool_action:
+      - logger.log: cooling
+    heat_cool_mode:
+      - logger.log: heat_cool
+    preset:
+      - name: Default
+        default_target_temperature_low: 18 °C
+        default_target_temperature_high: 22 °C
+    visual:
+      min_temperature: 10 °C
+      max_temperature: 30 °C
+
+button:
+  # mode only
+  - platform: template
+    id: btn_mode
+    name: "Set Mode Heat"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: HEAT
+
+  # mode + target_temperature_low + target_temperature_high
+  - platform: template
+    id: btn_mode_temps
+    name: "Set Mode Temps"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: HEAT_COOL
+          target_temperature_low: 19.0 °C
+          target_temperature_high: 23.0 °C
+
+  # target_temperature_low only
+  - platform: template
+    id: btn_low_only
+    name: "Set Low Only"
+    on_press:
+      - climate.control:
+          id: test_climate
+          target_temperature_low: 17.5 °C
+
+  # Lambda path: target_temperature_high computed at runtime
+  - platform: template
+    id: btn_lambda_high
+    name: "Lambda High"
+    on_press:
+      - climate.control:
+          id: test_climate
+          target_temperature_high: !lambda "return id(test_target_temp);"
+
+  # mode only — turn off via mode
+  - platform: template
+    id: btn_off
+    name: "Set Off"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: "OFF"
diff --git a/tests/integration/fixtures/cover_control_action.yaml b/tests/integration/fixtures/cover_control_action.yaml
new file mode 100644
index 0000000000..085d632796
--- /dev/null
+++ b/tests/integration/fixtures/cover_control_action.yaml
@@ -0,0 +1,111 @@
+esphome:
+  name: cover-control-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+globals:
+  - id: test_position
+    type: float
+    initial_value: "0.42"
+
+cover:
+  - platform: template
+    name: "Test Cover"
+    id: test_cover
+    has_position: true
+    optimistic: true
+    assumed_state: true
+    open_action:
+      - cover.template.publish:
+          id: test_cover
+          position: 1.0
+    close_action:
+      - cover.template.publish:
+          id: test_cover
+          position: 0.0
+    stop_action:
+      - cover.template.publish:
+          id: test_cover
+          current_operation: IDLE
+    tilt_action:
+      - lambda: |-
+          // Manually set tilt and publish
+          id(test_cover).tilt = tilt;
+          id(test_cover).publish_state();
+
+button:
+  # cover.control: position only
+  - platform: template
+    id: btn_position
+    name: "Set Position"
+    on_press:
+      - cover.control:
+          id: test_cover
+          position: 50%
+
+  # cover.control: tilt only
+  - platform: template
+    id: btn_tilt
+    name: "Set Tilt"
+    on_press:
+      - cover.control:
+          id: test_cover
+          tilt: 75%
+
+  # cover.control: position + tilt
+  - platform: template
+    id: btn_pos_tilt
+    name: "Set Pos Tilt"
+    on_press:
+      - cover.control:
+          id: test_cover
+          position: 25%
+          tilt: 30%
+
+  # cover.control: state alias for position
+  - platform: template
+    id: btn_open_state
+    name: "Open State"
+    on_press:
+      - cover.control:
+          id: test_cover
+          state: OPEN
+
+  # cover.control: lambda position (exercises lambda path)
+  - platform: template
+    id: btn_lambda_position
+    name: "Lambda Position"
+    on_press:
+      - cover.control:
+          id: test_cover
+          position: !lambda "return id(test_position);"
+
+  # cover.template.publish: position only
+  - platform: template
+    id: btn_publish_pos
+    name: "Publish Pos"
+    on_press:
+      - cover.template.publish:
+          id: test_cover
+          position: 0.6
+
+  # cover.template.publish: current_operation only
+  - platform: template
+    id: btn_publish_op
+    name: "Publish Op"
+    on_press:
+      - cover.template.publish:
+          id: test_cover
+          current_operation: OPENING
+
+  # cover.control: stop only — runs after Publish Op so the test can
+  # verify current_operation transitions OPENING -> IDLE.
+  - platform: template
+    id: btn_stop
+    name: "Stop Cover"
+    on_press:
+      - cover.control:
+          id: test_cover
+          stop: true
diff --git a/tests/integration/fixtures/fan_turn_on_action.yaml b/tests/integration/fixtures/fan_turn_on_action.yaml
new file mode 100644
index 0000000000..11bf033e48
--- /dev/null
+++ b/tests/integration/fixtures/fan_turn_on_action.yaml
@@ -0,0 +1,59 @@
+esphome:
+  name: fan-turn-on-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+globals:
+  - id: test_speed
+    type: int
+    initial_value: "2"
+
+fan:
+  - platform: template
+    id: test_fan
+    name: "Test Fan"
+    has_oscillating: true
+    has_direction: true
+    speed_count: 5
+
+button:
+  # fan.turn_on: speed only
+  - platform: template
+    id: btn_speed
+    name: "Set Speed"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          speed: 3
+
+  # fan.turn_on: oscillating + direction (no speed)
+  - platform: template
+    id: btn_oscillate_direction
+    name: "Set Oscillate Direction"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          oscillating: true
+          direction: REVERSE
+
+  # fan.turn_on: all three fields
+  - platform: template
+    id: btn_all_fields
+    name: "Set All Fields"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          oscillating: false
+          speed: 4
+          direction: FORWARD
+
+  # fan.turn_on: lambda for speed (exercises lambda path)
+  - platform: template
+    id: btn_lambda_speed
+    name: "Lambda Speed"
+    on_press:
+      - fan.turn_on:
+          id: test_fan
+          speed: !lambda "return id(test_speed);"
diff --git a/tests/integration/fixtures/host_mode_climate_basic_state.yaml b/tests/integration/fixtures/host_mode_climate_basic_state.yaml
index f79d684fc6..2bfd63ceff 100644
--- a/tests/integration/fixtures/host_mode_climate_basic_state.yaml
+++ b/tests/integration/fixtures/host_mode_climate_basic_state.yaml
@@ -1,5 +1,5 @@
 esphome:
-  name: host-climate-test
+  name: host-climate-basic-state
 host:
 api:
 logger:
@@ -10,6 +10,7 @@ climate:
     name: Dual-mode Thermostat
     sensor: host_thermostat_temperature_sensor
     humidity_sensor: host_thermostat_humidity_sensor
+    on_boot_restore_from: default_preset
     humidity_hysteresis: 1.0
     min_cooling_off_time: 20s
     min_cooling_run_time: 20s
diff --git a/tests/integration/fixtures/light_dim_relative_action.yaml b/tests/integration/fixtures/light_dim_relative_action.yaml
new file mode 100644
index 0000000000..b52cf65b89
--- /dev/null
+++ b/tests/integration/fixtures/light_dim_relative_action.yaml
@@ -0,0 +1,60 @@
+esphome:
+  name: light-dim-relative-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+output:
+  - platform: template
+    id: test_out
+    type: float
+    write_action:
+      - lambda: ""
+
+light:
+  - platform: monochromatic
+    name: "Test Light"
+    id: test_light
+    output: test_out
+    default_transition_length: 0s
+
+button:
+  # Set up: turn on at 50% brightness
+  - platform: template
+    id: btn_setup
+    name: "Setup"
+    on_press:
+      - light.turn_on:
+          id: test_light
+          brightness: 50%
+
+  # Test 1: dim_relative without transition_length (HasTransitionLength=false)
+  - platform: template
+    id: btn_dim_up
+    name: "Dim Up"
+    on_press:
+      - light.dim_relative:
+          id: test_light
+          relative_brightness: 25%
+
+  # Test 2: dim_relative with transition_length (HasTransitionLength=true)
+  - platform: template
+    id: btn_dim_down
+    name: "Dim Down"
+    on_press:
+      - light.dim_relative:
+          id: test_light
+          relative_brightness: -10%
+          transition_length: 0s
+
+  # Test 3: dim_relative with brightness limits
+  - platform: template
+    id: btn_dim_clamp
+    name: "Dim Clamp"
+    on_press:
+      - light.dim_relative:
+          id: test_light
+          relative_brightness: 50%
+          brightness_limits:
+            max_brightness: 80%
diff --git a/tests/integration/fixtures/light_toggle_action.yaml b/tests/integration/fixtures/light_toggle_action.yaml
new file mode 100644
index 0000000000..265d8ba1ac
--- /dev/null
+++ b/tests/integration/fixtures/light_toggle_action.yaml
@@ -0,0 +1,37 @@
+esphome:
+  name: light-toggle-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+output:
+  - platform: template
+    id: test_out
+    type: float
+    write_action:
+      - lambda: ""
+
+light:
+  - platform: monochromatic
+    name: "Test Light"
+    id: test_light
+    output: test_out
+    default_transition_length: 0s
+
+button:
+  # Test 1: light.toggle without transition_length (HasTransitionLength=false)
+  - platform: template
+    id: btn_toggle
+    name: "Toggle"
+    on_press:
+      - light.toggle: test_light
+
+  # Test 2: light.toggle with transition_length (HasTransitionLength=true)
+  - platform: template
+    id: btn_toggle_with_trans
+    name: "Toggle With Trans"
+    on_press:
+      - light.toggle:
+          id: test_light
+          transition_length: 0s
diff --git a/tests/integration/fixtures/scheduler_self_keyed.yaml b/tests/integration/fixtures/scheduler_self_keyed.yaml
new file mode 100644
index 0000000000..9a691136f3
--- /dev/null
+++ b/tests/integration/fixtures/scheduler_self_keyed.yaml
@@ -0,0 +1,112 @@
+esphome:
+  debug_scheduler: true  # Enable scheduler leak detection
+  name: scheduler-self-keyed-test
+  on_boot:
+    priority: -100
+    then:
+      - logger.log: "Starting scheduler self-keyed tests"
+
+host:
+api:
+logger:
+  level: VERBOSE
+
+globals:
+  - id: tests_done
+    type: bool
+    initial_value: 'false'
+
+script:
+  - id: test_self_keyed
+    then:
+      - logger.log: "Testing self-keyed scheduler API"
+      - lambda: |-
+          // Two distinct keys backed by addresses of static markers — they
+          // must not collide even though both are self-keyed and share no
+          // Component pointer. Static storage gives them stable, unique
+          // addresses for the lifetime of the program.
+          static int key_a_marker = 0;
+          static int key_b_marker = 0;
+          void *key_a = &key_a_marker;
+          void *key_b = &key_b_marker;
+
+          // ---- Test 1: Self-keyed timeout fires ----
+          App.scheduler.set_timeout(key_a, 50, []() {
+            ESP_LOGI("test", "Self timeout A fired");
+          });
+
+          // ---- Test 2: Self-keyed cancel cancels only that key ----
+          App.scheduler.set_timeout(key_b, 100, []() {
+            ESP_LOGE("test", "ERROR: Self timeout B should have been cancelled");
+          });
+          App.scheduler.cancel_timeout(key_b);
+
+          // ---- Test 3: Two independent self keys don't collide ----
+          // Using fresh static markers so neither matches key_a / key_b.
+          static int key_c_marker = 0;
+          static int key_d_marker = 0;
+          void *key_c = &key_c_marker;
+          void *key_d = &key_d_marker;
+          App.scheduler.set_timeout(key_c, 150, []() {
+            ESP_LOGI("test", "Self timeout C fired");
+          });
+          App.scheduler.set_timeout(key_d, 150, []() {
+            ESP_LOGI("test", "Self timeout D fired");
+          });
+
+          // ---- Test 4: Self-keyed and component-keyed don't collide ----
+          // Use a self pointer that happens to look like a Component-attached id.
+          // The scheduler must treat them as separate namespaces.
+          static int shared_marker = 0;
+          void *self_shared = &shared_marker;
+          App.scheduler.set_timeout(self_shared, 200, []() {
+            ESP_LOGI("test", "Self timeout shared fired");
+          });
+          App.scheduler.set_timeout(id(test_sensor), 7777U, 200, []() {
+            ESP_LOGI("test", "Component timeout 7777 fired");
+          });
+
+          // ---- Test 5: Self-keyed interval fires multiple times then cancels ----
+          static int interval_count = 0;
+          static int key_e_marker = 0;
+          void *key_e = &key_e_marker;
+          App.scheduler.set_interval(key_e, 80, [key_e]() {
+            interval_count++;
+            if (interval_count == 2) {
+              ESP_LOGI("test", "Self interval E fired twice");
+              App.scheduler.cancel_interval(key_e);
+            }
+          });
+
+          // ---- Test 6: Re-registering same self-key replaces the timer ----
+          // The old timer must NOT fire; only the new one does.
+          static int key_f_marker = 0;
+          void *key_f = &key_f_marker;
+          App.scheduler.set_timeout(key_f, 250, []() {
+            ESP_LOGE("test", "ERROR: Self timeout F first registration should have been replaced");
+          });
+          App.scheduler.set_timeout(key_f, 300, []() {
+            ESP_LOGI("test", "Self timeout F replacement fired");
+          });
+
+          // Log completion after all timers should have fired
+          App.scheduler.set_timeout(id(test_sensor), 9999U, 1500, []() {
+            ESP_LOGI("test", "All self-keyed tests complete");
+          });
+
+sensor:
+  - platform: template
+    name: Test Sensor
+    id: test_sensor
+    lambda: return 1.0;
+    update_interval: never
+
+interval:
+  - interval: 0.1s
+    then:
+      - if:
+          condition:
+            lambda: 'return id(tests_done) == false;'
+          then:
+            - lambda: 'id(tests_done) = true;'
+            - script.execute: test_self_keyed
diff --git a/tests/integration/fixtures/uart_mock_modbus_server.yaml b/tests/integration/fixtures/uart_mock_modbus_server.yaml
index b657a6fd21..cc5a59e242 100644
--- a/tests/integration/fixtures/uart_mock_modbus_server.yaml
+++ b/tests/integration/fixtures/uart_mock_modbus_server.yaml
@@ -86,9 +86,9 @@ modbus:
   uart_id: virtual_uart_dev
   role: server
 
-modbus_controller:
+modbus_server:
   - address: 1
-    server_registers:
+    registers:
       - address: 0x03
         value_type: U_WORD
         read_lambda: |-
diff --git a/tests/integration/fixtures/uart_mock_modbus_server_controller.yaml b/tests/integration/fixtures/uart_mock_modbus_server_controller.yaml
index f0f2c56a36..1e5f5a3389 100644
--- a/tests/integration/fixtures/uart_mock_modbus_server_controller.yaml
+++ b/tests/integration/fixtures/uart_mock_modbus_server_controller.yaml
@@ -33,7 +33,7 @@ uart_mock:
               data: !lambda return data;
   - id: virtual_uart_controller
     baud_rate: 9600
-    auto_start: true  # See comment on virtual_uart_server above
+    auto_start: true # See comment on virtual_uart_server above
     debug:
     on_tx:
       - then:
@@ -56,10 +56,11 @@ modbus_controller:
     update_interval: 1s
     id: modbus_controller_1
 
+modbus_server:
   - address: 1
     modbus_id: virtual_modbus_server
     id: modbus_server_1
-    server_registers:
+    registers:
       - address: 0x01
         value_type: U_WORD
         read_lambda: return 99;
diff --git a/tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml b/tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml
index 7ec67b03db..e68edd2271 100644
--- a/tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml
+++ b/tests/integration/fixtures/uart_mock_modbus_server_controller_multiple.yaml
@@ -36,7 +36,7 @@ uart_mock:
               data: !lambda return data;
   - id: virtual_uart_server_2
     baud_rate: 9600
-    auto_start: true  # See comment on virtual_uart_server above
+    auto_start: true # See comment on virtual_uart_server above
     debug:
     on_tx:
       - then:
@@ -48,7 +48,7 @@ uart_mock:
               data: !lambda return data;
   - id: virtual_uart_controller
     baud_rate: 9600
-    auto_start: true  # See comment on virtual_uart_server above
+    auto_start: true # See comment on virtual_uart_server above
     debug:
     on_tx:
       - then:
@@ -81,15 +81,16 @@ modbus_controller:
     update_interval: 1s
     id: modbus_controller_2
 
+modbus_server:
   - address: 1
     modbus_id: virtual_modbus_server
-    server_registers:
+    registers:
       - address: 0x01
         value_type: U_WORD
         read_lambda: return 919;
   - address: 2
     modbus_id: virtual_modbus_server_2
-    server_registers:
+    registers:
       - address: 0x01
         value_type: U_WORD
         read_lambda: return 929;
diff --git a/tests/integration/fixtures/uart_mock_modbus_server_controller_write.yaml b/tests/integration/fixtures/uart_mock_modbus_server_controller_write.yaml
index 3edcc73f07..94890e90de 100644
--- a/tests/integration/fixtures/uart_mock_modbus_server_controller_write.yaml
+++ b/tests/integration/fixtures/uart_mock_modbus_server_controller_write.yaml
@@ -33,7 +33,7 @@ uart_mock:
               data: !lambda return data;
   - id: virtual_uart_controller
     baud_rate: 9600
-    auto_start: true  # See comment on virtual_uart_server above
+    auto_start: true # See comment on virtual_uart_server above
     debug:
     on_tx:
       - then:
@@ -94,10 +94,11 @@ modbus_controller:
     update_interval: 2s
     id: modbus_controller_1
 
+modbus_server:
   - address: 1
     modbus_id: virtual_modbus_server
     id: modbus_server_1
-    server_registers:
+    registers:
       - address: 0x01
         value_type: U_WORD
         read_lambda: return id(stored_u_word);
diff --git a/tests/integration/fixtures/valve_control_action.yaml b/tests/integration/fixtures/valve_control_action.yaml
new file mode 100644
index 0000000000..4f43d16289
--- /dev/null
+++ b/tests/integration/fixtures/valve_control_action.yaml
@@ -0,0 +1,69 @@
+esphome:
+  name: valve-control-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+globals:
+  - id: test_position
+    type: float
+    initial_value: "0.42"
+
+valve:
+  - platform: template
+    name: "Test Valve"
+    id: test_valve
+    has_position: true
+    optimistic: true
+    assumed_state: true
+    open_action:
+      - valve.template.publish:
+          id: test_valve
+          position: 1.0
+    close_action:
+      - valve.template.publish:
+          id: test_valve
+          position: 0.0
+    stop_action:
+      - valve.template.publish:
+          id: test_valve
+          current_operation: IDLE
+
+button:
+  # valve.control: position only
+  - platform: template
+    id: btn_position
+    name: "Set Position"
+    on_press:
+      - valve.control:
+          id: test_valve
+          position: 50%
+
+  # valve.control: state alias for position 1.0
+  - platform: template
+    id: btn_open_state
+    name: "Open State"
+    on_press:
+      - valve.control:
+          id: test_valve
+          state: OPEN
+
+  # valve.control: lambda position (exercises lambda path)
+  - platform: template
+    id: btn_lambda_position
+    name: "Lambda Position"
+    on_press:
+      - valve.control:
+          id: test_valve
+          position: !lambda "return id(test_position);"
+
+  # valve.control: stop only — template valve's stop_action publishes
+  # current_operation: IDLE.
+  - platform: template
+    id: btn_stop
+    name: "Stop Valve"
+    on_press:
+      - valve.control:
+          id: test_valve
+          stop: true
diff --git a/tests/integration/state_utils.py b/tests/integration/state_utils.py
index d42b50ecdb..c8517aff09 100644
--- a/tests/integration/state_utils.py
+++ b/tests/integration/state_utils.py
@@ -8,6 +8,7 @@ import logging
 from typing import TypeVar
 
 from aioesphomeapi import (
+    APIClient,
     BinarySensorState,
     ButtonInfo,
     EntityInfo,
@@ -19,6 +20,42 @@ from aioesphomeapi import (
 _LOGGER = logging.getLogger(__name__)
 
 T = TypeVar("T", bound=EntityInfo)
+S = TypeVar("S", bound=EntityState)
+
+
+async def wait_for_state(
+    client: APIClient,
+    predicate: Callable[[EntityState], bool],
+    timeout: float = 5.0,
+) -> EntityState:
+    """Subscribe to states and wait for one matching ``predicate``.
+
+    Resolves with the first :class:`EntityState` for which ``predicate``
+    returns ``True``. Useful when a component publishes multiple states
+    during setup (e.g. before sensor readings arrive) and the test needs
+    to wait for the state to converge to expected values rather than
+    capturing whichever state happens to arrive first.
+
+    Args:
+        client: Connected API client.
+        predicate: Callable invoked for every received state; the first
+            state for which it returns ``True`` is returned.
+        timeout: Maximum time to wait in seconds.
+
+    Returns:
+        The first state matching ``predicate``.
+
+    Raises:
+        asyncio.TimeoutError: If no matching state arrives within ``timeout``.
+    """
+    future: asyncio.Future[EntityState] = asyncio.get_running_loop().create_future()
+
+    def on_state(state: EntityState) -> None:
+        if not future.done() and predicate(state):
+            future.set_result(state)
+
+    client.subscribe_states(on_state)
+    return await asyncio.wait_for(future, timeout=timeout)
 
 
 def find_entity(
diff --git a/tests/integration/test_binary_sensor_autorepeat_filter.py b/tests/integration/test_binary_sensor_autorepeat_filter.py
new file mode 100644
index 0000000000..443d5293f2
--- /dev/null
+++ b/tests/integration/test_binary_sensor_autorepeat_filter.py
@@ -0,0 +1,123 @@
+"""Integration test for the binary_sensor autorepeat filter.
+
+Verifies that the autorepeat filter:
+
+1. Passes the initial true through unchanged.
+2. Begins oscillating after the configured ``delay`` while the source stays true.
+3. Stops oscillating and emits a final false when the source goes false.
+
+This exercises both scheduled timers in ``AutorepeatFilter`` (the per-step
+``delay`` timer keyed off the filter ``this`` pointer and the on/off toggle
+timer keyed off ``&active_timing_``).
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from .state_utils import InitialStateHelper, SensorStateCollector, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_binary_sensor_autorepeat_filter(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Drive the source true and verify the downstream sensor oscillates."""
+    collector = SensorStateCollector(
+        sensor_names=[],
+        binary_sensor_names=["autorepeat_sensor"],
+    )
+
+    async with (
+        run_compiled(yaml_config),
+        api_client_connected() as client,
+    ):
+        device_info = await client.device_info()
+        assert device_info is not None
+        assert device_info.name == "test-autorepeat-filter"
+
+        entities, _ = await client.list_entities_services()
+        collector.build_key_mapping(entities)
+
+        press_button = require_entity(entities, "press", description="Press button")
+        release_button = require_entity(
+            entities, "release", description="Release button"
+        )
+
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(
+            initial_state_helper.on_state_wrapper(collector.on_state)
+        )
+
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        autorepeat_states = collector.binary_states["autorepeat_sensor"]
+
+        # Press: source becomes true, autorepeat passes the initial true through
+        # and then oscillates after the configured delay.
+        # Configured timings: delay=200ms, time_on=100ms, time_off=100ms.
+        # Expected within ~700ms:
+        #   true (0ms), false (200ms), true (300ms), false (400ms),
+        #   true (500ms), false (600ms)
+        client.button_command(press_button.key)
+
+        # Wait for at least 5 transitions to verify the oscillation pattern.
+        oscillation_seen = collector.add_waiter(lambda: len(autorepeat_states) >= 5)
+        try:
+            await asyncio.wait_for(oscillation_seen, timeout=2.0)
+        except TimeoutError:
+            pytest.fail(
+                f"Expected at least 5 autorepeat transitions, got {autorepeat_states}"
+            )
+
+        assert autorepeat_states[0] is True, (
+            f"First transition should be the pass-through true, got {autorepeat_states}"
+        )
+        # After the initial true and the configured delay, the filter must
+        # toggle false/true/false/... — verify the alternation pattern.
+        for index, value in enumerate(autorepeat_states):
+            expected = index % 2 == 0
+            assert value is expected, (
+                f"Expected alternating values starting with True, "
+                f"got {autorepeat_states} (mismatch at index {index})"
+            )
+
+        # Release: source becomes false, autorepeat must cancel both timers
+        # and settle on false. If the most recent oscillation was already
+        # false, the binary sensor will dedup and not emit a new state event;
+        # if it was true, exactly one final false transition arrives. Either
+        # way, the steady state must be false and no further toggles should
+        # arrive after a settle window longer than time_on + time_off.
+        was_true_before_release = autorepeat_states[-1] is True
+        before_count = len(autorepeat_states)
+        client.button_command(release_button.key)
+
+        if was_true_before_release:
+            settle_seen = collector.add_waiter(
+                lambda: len(autorepeat_states) > before_count
+            )
+            try:
+                await asyncio.wait_for(settle_seen, timeout=2.0)
+            except TimeoutError:
+                pytest.fail("Timeout waiting for autorepeat to settle to false")
+            assert autorepeat_states[-1] is False, (
+                f"After release, final state should be False, got {autorepeat_states}"
+            )
+
+        steady_count = len(autorepeat_states)
+        await asyncio.sleep(0.5)
+        assert len(autorepeat_states) == steady_count, (
+            f"Expected no further toggles after release, "
+            f"got {autorepeat_states[steady_count:]}"
+        )
+        assert autorepeat_states[-1] is False, (
+            f"Final autorepeat state should be False, got {autorepeat_states}"
+        )
diff --git a/tests/integration/test_climate_control_action.py b/tests/integration/test_climate_control_action.py
new file mode 100644
index 0000000000..2b0293b209
--- /dev/null
+++ b/tests/integration/test_climate_control_action.py
@@ -0,0 +1,84 @@
+"""Integration test for climate ControlAction.
+
+Tests that climate.control automation actions work correctly with the
+single stateless apply lambda/function pointer implementation. Exercises
+multiple field combinations and the lambda path.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateInfo,
+    ClimateMode,
+    ClimateState,
+    EntityState,
+)
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_climate_control_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test climate ControlAction with constants and lambdas."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        climate_state_future: asyncio.Future[ClimateState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, ClimateState)
+                and climate_state_future is not None
+                and not climate_state_future.done()
+            ):
+                climate_state_future.set_result(state)
+
+        async def wait_for_climate_state(timeout: float = 5.0) -> ClimateState:
+            nonlocal climate_state_future
+            climate_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(climate_state_future, timeout)
+            finally:
+                climate_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_climate", ClimateInfo)
+
+        async def press_and_wait(name: str) -> ClimateState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_climate_state()
+
+        # mode only — set HEAT
+        state = await press_and_wait("Set Mode Heat")
+        assert state.mode == ClimateMode.HEAT
+
+        # mode + target_temperature_low + target_temperature_high
+        state = await press_and_wait("Set Mode Temps")
+        assert state.mode == ClimateMode.HEAT_COOL
+        assert state.target_temperature_low == pytest.approx(19.0, abs=0.5)
+        assert state.target_temperature_high == pytest.approx(23.0, abs=0.5)
+
+        # target_temperature_low only
+        state = await press_and_wait("Set Low Only")
+        assert state.target_temperature_low == pytest.approx(17.5, abs=0.5)
+
+        # lambda path: target_temperature_high computed at runtime
+        state = await press_and_wait("Lambda High")
+        assert state.target_temperature_high == pytest.approx(21.5, abs=0.5)
+
+        # mode only — turn off via mode
+        state = await press_and_wait("Set Off")
+        assert state.mode == ClimateMode.OFF
diff --git a/tests/integration/test_cover_control_action.py b/tests/integration/test_cover_control_action.py
new file mode 100644
index 0000000000..9c7395371b
--- /dev/null
+++ b/tests/integration/test_cover_control_action.py
@@ -0,0 +1,92 @@
+"""Integration test for cover ControlAction and CoverPublishAction.
+
+Tests that cover.control and cover.template.publish automation actions
+work correctly with the single stateless apply lambda/function pointer
+implementation. Exercises multiple field combinations and the lambda path.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import ButtonInfo, CoverInfo, CoverState, EntityState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_cover_control_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test cover ControlAction/CoverPublishAction with constants and lambdas."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        cover_state_future: asyncio.Future[CoverState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, CoverState)
+                and cover_state_future is not None
+                and not cover_state_future.done()
+            ):
+                cover_state_future.set_result(state)
+
+        async def wait_for_cover_state(timeout: float = 5.0) -> CoverState:
+            nonlocal cover_state_future
+            cover_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(cover_state_future, timeout)
+            finally:
+                cover_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_cover", CoverInfo)
+
+        async def press_and_wait(name: str) -> CoverState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_cover_state()
+
+        # cover.control: position only
+        state = await press_and_wait("Set Position")
+        assert state.position == pytest.approx(0.5, abs=0.01)
+
+        # cover.control: tilt only
+        state = await press_and_wait("Set Tilt")
+        assert state.tilt == pytest.approx(0.75, abs=0.01)
+
+        # cover.control: position + tilt
+        state = await press_and_wait("Set Pos Tilt")
+        assert state.position == pytest.approx(0.25, abs=0.01)
+        assert state.tilt == pytest.approx(0.30, abs=0.01)
+
+        # cover.control: state alias for position 1.0
+        state = await press_and_wait("Open State")
+        assert state.position == pytest.approx(1.0, abs=0.01)
+
+        # cover.control: lambda position (test_position global = 0.42)
+        state = await press_and_wait("Lambda Position")
+        assert state.position == pytest.approx(0.42, abs=0.01)
+
+        # cover.template.publish: position only
+        state = await press_and_wait("Publish Pos")
+        assert state.position == pytest.approx(0.6, abs=0.01)
+
+        # cover.template.publish: current_operation only
+        state = await press_and_wait("Publish Op")
+        # CoverOperation.OPENING == 1
+        assert state.current_operation == 1
+
+        # cover.control: stop only — template cover's stop_action publishes
+        # current_operation: IDLE.
+        state = await press_and_wait("Stop Cover")
+        # CoverOperation.IDLE == 0
+        assert state.current_operation == 0
diff --git a/tests/integration/test_fan_turn_on_action.py b/tests/integration/test_fan_turn_on_action.py
new file mode 100644
index 0000000000..bce258cb5c
--- /dev/null
+++ b/tests/integration/test_fan_turn_on_action.py
@@ -0,0 +1,75 @@
+"""Integration test for fan TurnOnAction.
+
+Tests that fan.turn_on automation actions work correctly across multiple
+field combinations and the lambda path.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import ButtonInfo, EntityState, FanDirection, FanInfo, FanState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_fan_turn_on_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test fan TurnOnAction with constants and a lambda."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        fan_state_future: asyncio.Future[FanState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, FanState)
+                and fan_state_future is not None
+                and not fan_state_future.done()
+            ):
+                fan_state_future.set_result(state)
+
+        async def wait_for_fan_state(timeout: float = 5.0) -> FanState:
+            nonlocal fan_state_future
+            fan_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(fan_state_future, timeout)
+            finally:
+                fan_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_fan", FanInfo)
+
+        async def press_and_wait(name: str) -> FanState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_fan_state()
+
+        # speed only
+        state = await press_and_wait("Set Speed")
+        assert state.state is True
+        assert state.speed_level == 3
+
+        # oscillating + direction
+        state = await press_and_wait("Set Oscillate Direction")
+        assert state.oscillating is True
+        assert state.direction == FanDirection.REVERSE
+
+        # all three fields
+        state = await press_and_wait("Set All Fields")
+        assert state.oscillating is False
+        assert state.speed_level == 4
+        assert state.direction == FanDirection.FORWARD
+
+        # lambda path: speed computed at runtime (test_speed global = 2)
+        state = await press_and_wait("Lambda Speed")
+        assert state.speed_level == 2
diff --git a/tests/integration/test_host_mode_climate_basic_state.py b/tests/integration/test_host_mode_climate_basic_state.py
index 7d871ed5a8..0c82d28c3c 100644
--- a/tests/integration/test_host_mode_climate_basic_state.py
+++ b/tests/integration/test_host_mode_climate_basic_state.py
@@ -2,11 +2,17 @@
 
 from __future__ import annotations
 
-import aioesphomeapi
-from aioesphomeapi import ClimateAction, ClimateInfo, ClimateMode, ClimatePreset
+from aioesphomeapi import (
+    ClimateAction,
+    ClimateInfo,
+    ClimateMode,
+    ClimatePreset,
+    ClimateState,
+    EntityState,
+)
 import pytest
 
-from .state_utils import InitialStateHelper
+from .state_utils import wait_for_state
 from .types import APIClientConnectedFactory, RunCompiledFunction
 
 
@@ -18,32 +24,30 @@ async def test_host_mode_climate_basic_state(
 ) -> None:
     """Test basic climate state reporting."""
     async with run_compiled(yaml_config), api_client_connected() as client:
-        # Get entities and set up state synchronization
-        entities, services = await client.list_entities_services()
-        initial_state_helper = InitialStateHelper(entities)
+        entities, _ = await client.list_entities_services()
         climate_infos = [e for e in entities if isinstance(e, ClimateInfo)]
         assert len(climate_infos) >= 1, "Expected at least 1 climate entity"
-
-        # Subscribe with the wrapper (no-op callback since we just want initial states)
-        client.subscribe_states(initial_state_helper.on_state_wrapper(lambda _: None))
-
-        # Wait for all initial states to be broadcast
-        try:
-            await initial_state_helper.wait_for_initial_states()
-        except TimeoutError:
-            pytest.fail("Timeout waiting for initial states")
-
-        # Get the climate entity and its initial state
         test_climate = climate_infos[0]
-        climate_state = initial_state_helper.initial_states.get(test_climate.key)
 
-        assert climate_state is not None, "Climate initial state not found"
-        assert isinstance(climate_state, aioesphomeapi.ClimateState)
-        assert climate_state.mode == ClimateMode.OFF
-        assert climate_state.action == ClimateAction.OFF
-        assert climate_state.current_temperature == 22.0
-        assert climate_state.target_temperature_low == 18.0
-        assert climate_state.target_temperature_high == 24.0
-        assert climate_state.preset == ClimatePreset.HOME
-        assert climate_state.current_humidity == 42.0
-        assert climate_state.target_humidity == 20.0
+        # The thermostat publishes multiple states during setup as the
+        # temperature/humidity sensors come online. Wait for the state to
+        # converge to the expected default values rather than relying on
+        # whichever state happens to arrive first.
+        def is_default_state(state: EntityState) -> bool:
+            return (
+                isinstance(state, ClimateState)
+                and state.key == test_climate.key
+                and state.mode == ClimateMode.OFF
+                and state.action == ClimateAction.OFF
+                and state.current_temperature == 22.0
+                and state.target_temperature_low == 18.0
+                and state.target_temperature_high == 24.0
+                and state.preset == ClimatePreset.HOME
+                and state.current_humidity == 42.0
+                and state.target_humidity == 20.0
+            )
+
+        try:
+            await wait_for_state(client, is_default_state)
+        except TimeoutError:
+            pytest.fail("Climate did not converge to expected default state")
diff --git a/tests/integration/test_light_dim_relative_action.py b/tests/integration/test_light_dim_relative_action.py
new file mode 100644
index 0000000000..d5078f4409
--- /dev/null
+++ b/tests/integration/test_light_dim_relative_action.py
@@ -0,0 +1,72 @@
+"""Integration test for light::DimRelativeAction.
+
+Tests both DimRelativeAction<HasTransitionLength=false> and
+DimRelativeAction<HasTransitionLength=true> instantiations.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import ButtonInfo, EntityState, LightInfo, LightState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_light_dim_relative_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test light.dim_relative with and without transition_length."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        light_state_future: asyncio.Future[LightState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, LightState)
+                and light_state_future is not None
+                and not light_state_future.done()
+            ):
+                light_state_future.set_result(state)
+
+        async def wait_for_light_state(timeout: float = 5.0) -> LightState:
+            nonlocal light_state_future
+            light_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(light_state_future, timeout)
+            finally:
+                light_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_light", LightInfo)
+
+        async def press_and_wait(name: str) -> LightState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_light_state()
+
+        # Setup: turn on at 50%
+        state = await press_and_wait("Setup")
+        assert state.state is True
+        assert state.brightness == pytest.approx(0.5, abs=0.05)
+
+        # Test 1: dim_relative without transition_length: 50% + 25% = 75%
+        state = await press_and_wait("Dim Up")
+        assert state.brightness == pytest.approx(0.75, abs=0.05)
+
+        # Test 2: dim_relative with transition_length: 75% - 10% = 65%
+        state = await press_and_wait("Dim Down")
+        assert state.brightness == pytest.approx(0.65, abs=0.05)
+
+        # Test 3: dim_relative with max_brightness limit: 65% + 50% clamped to 80%
+        state = await press_and_wait("Dim Clamp")
+        assert state.brightness == pytest.approx(0.80, abs=0.05)
diff --git a/tests/integration/test_light_toggle_action.py b/tests/integration/test_light_toggle_action.py
new file mode 100644
index 0000000000..ffbadabb5b
--- /dev/null
+++ b/tests/integration/test_light_toggle_action.py
@@ -0,0 +1,67 @@
+"""Integration test for light::ToggleAction.
+
+Tests both ToggleAction<HasTransitionLength=false> and
+ToggleAction<HasTransitionLength=true> instantiations.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import ButtonInfo, EntityState, LightInfo, LightState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_light_toggle_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test light.toggle with and without transition_length."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        light_state_future: asyncio.Future[LightState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, LightState)
+                and light_state_future is not None
+                and not light_state_future.done()
+            ):
+                light_state_future.set_result(state)
+
+        async def wait_for_light_state(timeout: float = 5.0) -> LightState:
+            nonlocal light_state_future
+            light_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(light_state_future, timeout)
+            finally:
+                light_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_light", LightInfo)
+
+        async def press_and_wait(name: str) -> LightState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_light_state()
+
+        # Test 1: toggle without transition_length flips off->on
+        state = await press_and_wait("Toggle")
+        assert state.state is True
+
+        # Test 2: toggle with transition_length flips on->off
+        state = await press_and_wait("Toggle With Trans")
+        assert state.state is False
+
+        # Test 3: toggle without transition_length flips off->on again
+        state = await press_and_wait("Toggle")
+        assert state.state is True
diff --git a/tests/integration/test_scheduler_self_keyed.py b/tests/integration/test_scheduler_self_keyed.py
new file mode 100644
index 0000000000..e0825ea825
--- /dev/null
+++ b/tests/integration/test_scheduler_self_keyed.py
@@ -0,0 +1,96 @@
+"""Test the self-keyed scheduler API.
+
+Verifies that `Scheduler::set_timeout(const void *, ...)` /
+`set_interval(const void *, ...)` and the matching `cancel_*(const void *)`
+overloads behave correctly: callbacks fire, distinct keys don't collide,
+self-keyed and component-keyed namespaces are independent, and re-registering
+the same key replaces the existing timer.
+"""
+
+import asyncio
+import re
+
+import pytest
+
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_scheduler_self_keyed(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test self-keyed scheduler API."""
+    self_a_fired = asyncio.Event()
+    self_b_error = asyncio.Event()
+    self_c_fired = asyncio.Event()
+    self_d_fired = asyncio.Event()
+    self_shared_fired = asyncio.Event()
+    component_7777_fired = asyncio.Event()
+    self_interval_done = asyncio.Event()
+    self_f_first_error = asyncio.Event()
+    self_f_replacement_fired = asyncio.Event()
+    all_tests_complete = asyncio.Event()
+
+    def on_log_line(line: str) -> None:
+        clean_line = re.sub(r"\x1b\[[0-9;]*m", "", line)
+
+        if "Self timeout A fired" in clean_line:
+            self_a_fired.set()
+        elif "ERROR: Self timeout B" in clean_line:
+            self_b_error.set()
+        elif "Self timeout C fired" in clean_line:
+            self_c_fired.set()
+        elif "Self timeout D fired" in clean_line:
+            self_d_fired.set()
+        elif "Self timeout shared fired" in clean_line:
+            self_shared_fired.set()
+        elif "Component timeout 7777 fired" in clean_line:
+            component_7777_fired.set()
+        elif "Self interval E fired twice" in clean_line:
+            self_interval_done.set()
+        elif "ERROR: Self timeout F first registration" in clean_line:
+            self_f_first_error.set()
+        elif "Self timeout F replacement fired" in clean_line:
+            self_f_replacement_fired.set()
+        elif "All self-keyed tests complete" in clean_line:
+            all_tests_complete.set()
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+        device_info = await client.device_info()
+        assert device_info is not None
+        assert device_info.name == "scheduler-self-keyed-test"
+
+        try:
+            await asyncio.wait_for(all_tests_complete.wait(), timeout=5.0)
+        except TimeoutError:
+            pytest.fail("Not all self-keyed tests completed within 5 seconds")
+
+        # Test 1: self-keyed timeout fires
+        assert self_a_fired.is_set(), "Self timeout A should have fired"
+
+        # Test 2: cancel_timeout(self) actually cancels
+        assert not self_b_error.is_set(), "Self timeout B should have been cancelled"
+
+        # Test 3: distinct self keys don't collide
+        assert self_c_fired.is_set(), "Self timeout C should have fired"
+        assert self_d_fired.is_set(), "Self timeout D should have fired"
+
+        # Test 4: self-keyed and component-keyed namespaces are independent
+        assert self_shared_fired.is_set(), "Self timeout shared should have fired"
+        assert component_7777_fired.is_set(), "Component timeout 7777 should have fired"
+
+        # Test 5: self-keyed interval fires repeatedly and cancels cleanly
+        assert self_interval_done.is_set(), "Self interval E should have fired twice"
+
+        # Test 6: re-registering same self-key replaces the previous timer
+        assert not self_f_first_error.is_set(), (
+            "Self timeout F first registration should have been replaced"
+        )
+        assert self_f_replacement_fired.is_set(), (
+            "Self timeout F replacement should have fired"
+        )
diff --git a/tests/integration/test_valve_control_action.py b/tests/integration/test_valve_control_action.py
new file mode 100644
index 0000000000..d6515b8960
--- /dev/null
+++ b/tests/integration/test_valve_control_action.py
@@ -0,0 +1,72 @@
+"""Integration test for valve ControlAction.
+
+Tests that valve.control automation actions work correctly across multiple
+field combinations and the lambda path.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import ButtonInfo, EntityState, ValveInfo, ValveOperation, ValveState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_valve_control_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test valve ControlAction with constants and a lambda."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        valve_state_future: asyncio.Future[ValveState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, ValveState)
+                and valve_state_future is not None
+                and not valve_state_future.done()
+            ):
+                valve_state_future.set_result(state)
+
+        async def wait_for_valve_state(timeout: float = 5.0) -> ValveState:
+            nonlocal valve_state_future
+            valve_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(valve_state_future, timeout)
+            finally:
+                valve_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_valve", ValveInfo)
+
+        async def press_and_wait(name: str) -> ValveState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_valve_state()
+
+        # valve.control: position only
+        state = await press_and_wait("Set Position")
+        assert state.position == pytest.approx(0.5, abs=0.01)
+
+        # valve.control: state alias for position 1.0
+        state = await press_and_wait("Open State")
+        assert state.position == pytest.approx(1.0, abs=0.01)
+
+        # valve.control: lambda position (test_position global = 0.42)
+        state = await press_and_wait("Lambda Position")
+        assert state.position == pytest.approx(0.42, abs=0.01)
+
+        # valve.control: stop only — template valve's stop_action publishes
+        # current_operation: IDLE.
+        state = await press_and_wait("Stop Valve")
+        assert state.current_operation == ValveOperation.IDLE
diff --git a/tests/script/test_check_import_time.py b/tests/script/test_check_import_time.py
new file mode 100644
index 0000000000..223c58002c
--- /dev/null
+++ b/tests/script/test_check_import_time.py
@@ -0,0 +1,191 @@
+"""Unit tests for script/check_import_time.py."""
+
+from __future__ import annotations
+
+import importlib.util
+import json
+import os
+from pathlib import Path
+import sys
+from unittest.mock import patch
+
+import pytest
+
+# Load the script-under-test as `check_import_time` (it's a hyphenated path
+# inside `script/` that mirrors the existing `determine_jobs` pattern).
+script_dir = os.path.abspath(
+    os.path.join(os.path.dirname(__file__), "..", "..", "script")
+)
+sys.path.insert(0, script_dir)
+spec = importlib.util.spec_from_file_location(
+    "check_import_time", os.path.join(script_dir, "check_import_time.py")
+)
+check_import_time = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(check_import_time)
+
+
+def _entry(name: str, self_us: int, cumulative_us: int) -> dict:
+    """Build a minimal HAR entry matching `importtime_waterfall --har`."""
+    return {
+        "request": {"url": name},
+        "time": cumulative_us,
+        "timings": {"receive": self_us, "wait": cumulative_us - self_us},
+    }
+
+
+def _har(*entries: dict) -> dict:
+    return {"log": {"entries": list(entries)}}
+
+
+def test_root_cumulative_us_returns_time_for_root_module() -> None:
+    har = _har(
+        _entry("dep_a", 500, 500),
+        _entry("dep_b", 300, 300),
+        _entry("esphome.__main__", 100, 1000),
+    )
+    assert check_import_time.root_cumulative_us(har, "esphome.__main__") == 1000
+
+
+def test_root_cumulative_us_missing_module_raises() -> None:
+    har = _har(_entry("something.else", 100, 100))
+    with pytest.raises(RuntimeError, match="No HAR entry for 'esphome.__main__'"):
+        check_import_time.root_cumulative_us(har, "esphome.__main__")
+
+
+def test_top_offenders_ranks_by_self_time_descending() -> None:
+    har = _har(
+        _entry("small", 100, 100),
+        _entry("big", 5000, 5000),
+        _entry("medium", 2000, 2500),
+    )
+    result = check_import_time.top_offenders(har, n=10)
+    assert [name for name, _, _ in result] == ["big", "medium", "small"]
+    assert result[0] == ("big", 5000, 5000)
+
+
+def test_top_offenders_respects_n_limit() -> None:
+    har = _har(*[_entry(f"m{i}", i * 100, i * 100) for i in range(1, 20)])
+    assert len(check_import_time.top_offenders(har, n=5)) == 5
+
+
+def test_top_offenders_dedupes_repeat_names_keeping_first() -> None:
+    har = _har(
+        _entry("pkg", 5000, 5000),
+        _entry("pkg", 100, 100),  # reimport later in trace
+        _entry("other", 1000, 1000),
+    )
+    result = check_import_time.top_offenders(har, n=10)
+    assert [name for name, _, _ in result] == ["pkg", "other"]
+    # First occurrence wins
+    assert ("pkg", 5000, 5000) in result
+
+
+def test_format_us_switches_to_ms_at_threshold() -> None:
+    assert check_import_time._format_us(500) == "500us"
+    assert check_import_time._format_us(999) == "999us"
+    assert check_import_time._format_us(1000) == "1.0ms"
+    assert check_import_time._format_us(12345) == "12.3ms"
+
+
+def test_read_write_budget_roundtrip(tmp_path: Path) -> None:
+    budget_path = tmp_path / "budget.json"
+    with patch.object(check_import_time, "BUDGET_PATH", budget_path):
+        assert check_import_time.read_budget() == {}
+        check_import_time.write_budget(cumulative_us=12345, margin_pct=20)
+        loaded = check_import_time.read_budget()
+    assert loaded["cumulative_us"] == 12345
+    assert loaded["margin_pct"] == 20
+    assert loaded["target_module"] == check_import_time.TARGET_MODULE
+
+
+def test_cmd_check_passes_when_measured_within_ceiling(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    budget_path = tmp_path / "budget.json"
+    budget_path.write_text(
+        json.dumps(
+            {
+                "target_module": check_import_time.TARGET_MODULE,
+                "margin_pct": 15,
+                "cumulative_us": 100000,  # 100ms
+            }
+        )
+    )
+    # Measured 90ms: inside 100ms + 15% = 115ms ceiling
+    har = _har(_entry(check_import_time.TARGET_MODULE, 1000, 90000))
+    args = type("A", (), {"har": None})()
+    with (
+        patch.object(check_import_time, "BUDGET_PATH", budget_path),
+        patch.object(check_import_time, "measure", return_value=har),
+    ):
+        rc = check_import_time.cmd_check(args)
+    assert rc == 0
+    out = capsys.readouterr().out
+    assert "measured   esphome.__main__:" in out
+    assert "budget 100.0ms" in out
+
+
+def test_cmd_check_fails_when_measured_exceeds_ceiling(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    budget_path = tmp_path / "budget.json"
+    budget_path.write_text(
+        json.dumps(
+            {
+                "target_module": check_import_time.TARGET_MODULE,
+                "margin_pct": 15,
+                "cumulative_us": 100000,
+            }
+        )
+    )
+    # Measured 120ms: over 100ms + 15% = 115ms ceiling
+    har = _har(
+        _entry("offender_a", 10000, 10000),
+        _entry(check_import_time.TARGET_MODULE, 1000, 120000),
+    )
+    args = type("A", (), {"har": None})()
+    with (
+        patch.object(check_import_time, "BUDGET_PATH", budget_path),
+        patch.object(check_import_time, "measure", return_value=har),
+    ):
+        rc = check_import_time.cmd_check(args)
+    assert rc == 1
+    err = capsys.readouterr().err
+    assert "REGRESSION" in err
+    assert "120.0ms" in err
+    assert "offender_a" in err  # top offender table
+
+
+def test_cmd_check_returns_2_when_budget_missing(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    budget_path = tmp_path / "nonexistent.json"
+    args = type("A", (), {"har": None})()
+    with patch.object(check_import_time, "BUDGET_PATH", budget_path):
+        rc = check_import_time.cmd_check(args)
+    assert rc == 2
+    assert "missing" in capsys.readouterr().err
+
+
+def test_cmd_check_writes_har_when_path_given(tmp_path: Path) -> None:
+    budget_path = tmp_path / "budget.json"
+    budget_path.write_text(
+        json.dumps(
+            {
+                "target_module": check_import_time.TARGET_MODULE,
+                "margin_pct": 15,
+                "cumulative_us": 100000,
+            }
+        )
+    )
+    har_path = tmp_path / "out.har"
+    har_text = json.dumps(_har(_entry(check_import_time.TARGET_MODULE, 1000, 80000)))
+    args = type("A", (), {"har": str(har_path)})()
+    with (
+        patch.object(check_import_time, "BUDGET_PATH", budget_path),
+        patch.object(check_import_time, "run_waterfall", return_value=har_text),
+    ):
+        rc = check_import_time.cmd_check(args)
+    assert rc == 0
+    assert har_path.exists()
+    assert json.loads(har_path.read_text()) == json.loads(har_text)
diff --git a/tests/script/test_determine_jobs.py b/tests/script/test_determine_jobs.py
index 2c726734fe..cc795bc553 100644
--- a/tests/script/test_determine_jobs.py
+++ b/tests/script/test_determine_jobs.py
@@ -56,6 +56,20 @@ def mock_should_run_python_linters() -> Generator[Mock, None, None]:
         yield mock
 
 
+@pytest.fixture
+def mock_should_run_import_time() -> Generator[Mock, None, None]:
+    """Mock should_run_import_time from determine_jobs."""
+    with patch.object(determine_jobs, "should_run_import_time") as mock:
+        yield mock
+
+
+@pytest.fixture
+def mock_should_run_device_builder() -> Generator[Mock, None, None]:
+    """Mock should_run_device_builder from determine_jobs."""
+    with patch.object(determine_jobs, "should_run_device_builder") as mock:
+        yield mock
+
+
 @pytest.fixture
 def mock_determine_cpp_unit_tests() -> Generator[Mock, None, None]:
     """Mock determine_cpp_unit_tests from helpers."""
@@ -91,6 +105,8 @@ def test_main_all_tests_should_run(
     mock_should_run_clang_tidy: Mock,
     mock_should_run_clang_format: Mock,
     mock_should_run_python_linters: Mock,
+    mock_should_run_import_time: Mock,
+    mock_should_run_device_builder: Mock,
     mock_changed_files: Mock,
     mock_determine_cpp_unit_tests: Mock,
     capsys: pytest.CaptureFixture[str],
@@ -104,6 +120,8 @@ def test_main_all_tests_should_run(
     mock_should_run_clang_tidy.return_value = True
     mock_should_run_clang_format.return_value = True
     mock_should_run_python_linters.return_value = True
+    mock_should_run_import_time.return_value = True
+    mock_should_run_device_builder.return_value = True
     mock_determine_cpp_unit_tests.return_value = (False, ["wifi", "api", "sensor"])
 
     # Mock changed_files to return non-component files (to avoid memory impact)
@@ -113,10 +131,19 @@ def test_main_all_tests_should_run(
         "esphome/helpers.py",
     ]
 
+    # Stable, deterministic stand-in for the tests/integration/ glob so the
+    # bucket assertions don't drift with the real test count.
+    fake_test_files = [f"tests/integration/test_{i:03d}.py" for i in range(15)]
+
     # Run main function with mocked argv
     with (
         patch("sys.argv", ["determine-jobs.py"]),
         patch.object(determine_jobs, "_is_clang_tidy_full_scan", return_value=False),
+        patch.object(
+            determine_jobs,
+            "_all_integration_test_files",
+            return_value=fake_test_files,
+        ),
         patch.object(
             determine_jobs,
             "get_changed_components",
@@ -152,12 +179,30 @@ def test_main_all_tests_should_run(
     output = json.loads(captured.out)
 
     assert output["integration_tests"] is True
-    assert output["integration_tests_run_all"] is True
-    assert output["integration_test_files"] == []
+    # run_all=True expands to the full glob and pre-buckets into 3 parts.
+    # Each bucket's `tests` is a JSON list of file paths.
+    assert isinstance(output["integration_test_buckets"], list)
+    assert len(output["integration_test_buckets"]) == 3
+    assert [b["name"] for b in output["integration_test_buckets"]] == [
+        "1/3",
+        "2/3",
+        "3/3",
+    ]
+    for bucket in output["integration_test_buckets"]:
+        assert isinstance(bucket["tests"], list)
+        for path in bucket["tests"]:
+            assert isinstance(path, str)
+    bucket_files = [f for b in output["integration_test_buckets"] for f in b["tests"]]
+    assert bucket_files == fake_test_files
+    # Bucket sizes are balanced (max-min difference at most 1).
+    sizes = [len(b["tests"]) for b in output["integration_test_buckets"]]
+    assert max(sizes) - min(sizes) <= 1
     assert output["clang_tidy"] is True
     assert output["clang_tidy_mode"] in ["nosplit", "split"]
     assert output["clang_format"] is True
     assert output["python_linters"] is True
+    assert output["import_time"] is True
+    assert output["device_builder"] is True
     assert output["changed_components"] == ["wifi", "api", "sensor"]
     # changed_components_with_tests will only include components that actually have test files
     assert "changed_components_with_tests" in output
@@ -189,6 +234,8 @@ def test_main_no_tests_should_run(
     mock_should_run_clang_tidy: Mock,
     mock_should_run_clang_format: Mock,
     mock_should_run_python_linters: Mock,
+    mock_should_run_import_time: Mock,
+    mock_should_run_device_builder: Mock,
     mock_changed_files: Mock,
     mock_determine_cpp_unit_tests: Mock,
     capsys: pytest.CaptureFixture[str],
@@ -202,6 +249,8 @@ def test_main_no_tests_should_run(
     mock_should_run_clang_tidy.return_value = False
     mock_should_run_clang_format.return_value = False
     mock_should_run_python_linters.return_value = False
+    mock_should_run_import_time.return_value = False
+    mock_should_run_device_builder.return_value = False
     mock_determine_cpp_unit_tests.return_value = (False, [])
 
     # Mock changed_files to return no component files
@@ -235,12 +284,13 @@ def test_main_no_tests_should_run(
     output = json.loads(captured.out)
 
     assert output["integration_tests"] is False
-    assert output["integration_tests_run_all"] is False
-    assert output["integration_test_files"] == []
+    assert output["integration_test_buckets"] == []
     assert output["clang_tidy"] is False
     assert output["clang_tidy_mode"] == "disabled"
     assert output["clang_format"] is False
     assert output["python_linters"] is False
+    assert output["import_time"] is False
+    assert output["device_builder"] is False
     assert output["changed_components"] == []
     assert output["changed_components_with_tests"] == []
     assert output["component_test_count"] == 0
@@ -261,6 +311,8 @@ def test_main_with_branch_argument(
     mock_should_run_clang_tidy: Mock,
     mock_should_run_clang_format: Mock,
     mock_should_run_python_linters: Mock,
+    mock_should_run_import_time: Mock,
+    mock_should_run_device_builder: Mock,
     mock_changed_files: Mock,
     mock_determine_cpp_unit_tests: Mock,
     capsys: pytest.CaptureFixture[str],
@@ -274,6 +326,8 @@ def test_main_with_branch_argument(
     mock_should_run_clang_tidy.return_value = True
     mock_should_run_clang_format.return_value = False
     mock_should_run_python_linters.return_value = True
+    mock_should_run_import_time.return_value = True
+    mock_should_run_device_builder.return_value = True
     mock_determine_cpp_unit_tests.return_value = (False, ["mqtt"])
 
     # Mock changed_files to return non-component files (to avoid memory impact)
@@ -310,18 +364,21 @@ def test_main_with_branch_argument(
     mock_should_run_clang_tidy.assert_called_once_with("main")
     mock_should_run_clang_format.assert_called_once_with("main")
     mock_should_run_python_linters.assert_called_once_with("main")
+    mock_should_run_import_time.assert_called_once_with("main")
+    mock_should_run_device_builder.assert_called_once_with("main")
 
     # Check output
     captured = capsys.readouterr()
     output = json.loads(captured.out)
 
     assert output["integration_tests"] is False
-    assert output["integration_tests_run_all"] is False
-    assert output["integration_test_files"] == []
+    assert output["integration_test_buckets"] == []
     assert output["clang_tidy"] is True
     assert output["clang_tidy_mode"] in ["nosplit", "split"]
     assert output["clang_format"] is False
     assert output["python_linters"] is True
+    assert output["import_time"] is True
+    assert output["device_builder"] is True
     assert output["changed_components"] == ["mqtt"]
     # changed_components_with_tests will only include components that actually have test files
     assert "changed_components_with_tests" in output
@@ -340,6 +397,59 @@ def test_main_with_branch_argument(
     assert output["cpp_unit_tests_components"] == ["mqtt"]
 
 
+def test_compute_integration_test_buckets_empty() -> None:
+    """No integration tests scheduled => (False, [])."""
+    run, buckets = determine_jobs._compute_integration_test_buckets(False, [])
+    assert run is False
+    assert buckets == []
+
+
+def test_compute_integration_test_buckets_below_threshold() -> None:
+    """A small explicit list (<= threshold) => single 1/1 bucket with that list."""
+    files = [f"tests/integration/test_{name}.py" for name in ("c", "a", "b")]
+    run, buckets = determine_jobs._compute_integration_test_buckets(False, files)
+    assert run is True
+    assert buckets == [{"name": "1/1", "tests": sorted(files)}]
+
+
+def test_compute_integration_test_buckets_at_threshold_stays_single() -> None:
+    """Exactly INTEGRATION_TESTS_SPLIT_THRESHOLD files => still one bucket
+    (the split kicks in only when count is strictly greater than threshold)."""
+    files = [
+        f"tests/integration/test_{i:02d}.py"
+        for i in range(determine_jobs.INTEGRATION_TESTS_SPLIT_THRESHOLD)
+    ]
+    run, buckets = determine_jobs._compute_integration_test_buckets(False, files)
+    assert run is True
+    assert len(buckets) == 1
+    assert buckets[0]["name"] == "1/1"
+    assert buckets[0]["tests"] == sorted(files)
+
+
+def test_compute_integration_test_buckets_just_over_threshold_splits() -> None:
+    """One file over the threshold triggers the 3-bucket fan-out, balanced."""
+    n = determine_jobs.INTEGRATION_TESTS_SPLIT_THRESHOLD + 1
+    files = [f"tests/integration/test_{i:02d}.py" for i in range(n)]
+    run, buckets = determine_jobs._compute_integration_test_buckets(False, files)
+    assert run is True
+    assert [b["name"] for b in buckets] == ["1/3", "2/3", "3/3"]
+    union = [path for b in buckets for path in b["tests"]]
+    assert union == sorted(files)
+    sizes = [len(b["tests"]) for b in buckets]
+    assert max(sizes) - min(sizes) <= 1
+
+
+def test_compute_integration_test_buckets_run_all_with_empty_glob_disables_run() -> (
+    None
+):
+    """run_all=True but glob returns no files => run suppressed (otherwise
+    pytest would collect tests outside tests/integration/)."""
+    with patch.object(determine_jobs, "_all_integration_test_files", return_value=[]):
+        run, buckets = determine_jobs._compute_integration_test_buckets(True, [])
+    assert run is False
+    assert buckets == []
+
+
 def test_determine_integration_tests(
     monkeypatch: pytest.MonkeyPatch,
 ) -> None:
@@ -597,6 +707,126 @@ def test_should_run_python_linters_with_branch() -> None:
         mock_changed.assert_called_once_with("release")
 
 
+@pytest.mark.parametrize(
+    ("changed_files", "expected_result"),
+    [
+        # esphome Python files trigger the check
+        (["esphome/__main__.py"], True),
+        (["esphome/components/wifi/__init__.py"], True),
+        (["esphome/core/config.py"], True),
+        (["esphome/types.pyi"], True),
+        # Dependency declarations and the check's own files trigger
+        (["requirements.txt"], True),
+        (["requirements_dev.txt"], True),
+        (["requirements_test.txt"], True),
+        (["pyproject.toml"], True),
+        (["script/check_import_time.py"], True),
+        (["script/import_time_budget.json"], True),
+        # Mixed: any triggering file is enough
+        (["docs/README.md", "esphome/config.py"], True),
+        # Python files outside esphome/ don't trigger
+        (["script/some_other_script.py"], False),
+        (["tests/script/test_determine_jobs.py"], False),
+        # Non-Python changes don't trigger
+        (["esphome/core/component.cpp"], False),
+        (["tests/components/wifi/test.esp32-idf.yaml"], False),
+        (["README.md"], False),
+        ([], False),
+    ],
+)
+def test_should_run_import_time(
+    changed_files: list[str], expected_result: bool
+) -> None:
+    """Test should_run_import_time function."""
+    with patch.object(determine_jobs, "changed_files", return_value=changed_files):
+        result = determine_jobs.should_run_import_time()
+        assert result == expected_result
+
+
+def test_should_run_import_time_with_branch() -> None:
+    """Test should_run_import_time with branch argument."""
+    with patch.object(determine_jobs, "changed_files") as mock_changed:
+        mock_changed.return_value = []
+        determine_jobs.should_run_import_time("release")
+        mock_changed.assert_called_once_with("release")
+
+
+@pytest.mark.parametrize(
+    ("changed_files", "expected_result"),
+    [
+        # esphome Python files trigger downstream device-builder tests
+        (["esphome/__main__.py"], True),
+        (["esphome/components/wifi/__init__.py"], True),
+        (["esphome/core/config.py"], True),
+        (["esphome/types.pyi"], True),
+        # Runtime dependency changes trigger
+        (["requirements.txt"], True),
+        (["pyproject.toml"], True),
+        # Non-C++ files packaged with esphome trigger -- device-builder
+        # picks them up because esphome's pyproject sets
+        # include-package-data = true.
+        (["esphome/idf_component.yml"], True),
+        (["esphome/dashboard/templates/index.html"], True),
+        (["esphome/components/api/api_pb2_service.json"], True),
+        # Mixed: any triggering file is enough
+        (["docs/README.md", "esphome/config.py"], True),
+        # Dev/test-only dependency changes don't trigger device-builder
+        # (they don't affect the importable surface device-builder uses)
+        (["requirements_dev.txt"], False),
+        (["requirements_test.txt"], False),
+        # Files outside esphome/ don't trigger
+        (["script/some_other_script.py"], False),
+        (["tests/script/test_determine_jobs.py"], False),
+        # C++ files under esphome/ don't trigger -- they only affect
+        # compiled firmware, not the Python install device-builder pulls in.
+        (["esphome/core/component.cpp"], False),
+        (["esphome/core/component.h"], False),
+        (["esphome/components/wifi/wifi_component.cpp"], False),
+        # Files outside esphome/ entirely
+        (["tests/components/wifi/test.esp32-idf.yaml"], False),
+        (["README.md"], False),
+        ([], False),
+    ],
+)
+def test_should_run_device_builder(
+    changed_files: list[str], expected_result: bool
+) -> None:
+    """Test should_run_device_builder function (non-beta/release target)."""
+    with (
+        patch.object(determine_jobs, "changed_files", return_value=changed_files),
+        # Mock target branch to "dev" so the beta/release skip is bypassed
+        # for these per-file behavior checks.
+        patch.object(determine_jobs, "get_target_branch", return_value="dev"),
+    ):
+        result = determine_jobs.should_run_device_builder()
+        assert result == expected_result
+
+
+def test_should_run_device_builder_with_branch() -> None:
+    """Test should_run_device_builder with branch argument."""
+    with (
+        patch.object(determine_jobs, "changed_files") as mock_changed,
+        patch.object(determine_jobs, "get_target_branch", return_value="dev"),
+    ):
+        mock_changed.return_value = []
+        determine_jobs.should_run_device_builder("release")
+        mock_changed.assert_called_once_with("release")
+
+
+@pytest.mark.parametrize("target_branch", ["beta", "release", "release-2026.5"])
+def test_should_run_device_builder_skips_beta_release(target_branch: str) -> None:
+    """Beta/release target branches skip device-builder (lag behind device-builder@main)."""
+    with (
+        patch.object(determine_jobs, "get_target_branch", return_value=target_branch),
+        patch.object(determine_jobs, "changed_files") as mock_changed,
+    ):
+        # Even with a triggering file present, the target-branch guard wins.
+        mock_changed.return_value = ["esphome/__main__.py"]
+        assert determine_jobs.should_run_device_builder() is False
+        # changed_files shouldn't even be consulted -- the guard short-circuits.
+        mock_changed.assert_not_called()
+
+
 @pytest.mark.parametrize(
     ("changed_files", "expected_result"),
     [
diff --git a/tests/script/test_test_helpers.py b/tests/script/test_test_helpers.py
index 467940fc33..3149712563 100644
--- a/tests/script/test_test_helpers.py
+++ b/tests/script/test_test_helpers.py
@@ -258,3 +258,161 @@ def test_load_wraps_platform_component(tmp_path: Path) -> None:
     assert key == "bthome.sensor"
     assert isinstance(installed, ComponentManifestOverride)
     assert installed.to_code is None
+
+
+# ---------------------------------------------------------------------------
+# populate_dependency_config
+# ---------------------------------------------------------------------------
+
+
+def _make_component_stub(
+    *,
+    multi_conf: bool = False,
+    is_platform_component: bool = False,
+    config_schema=None,
+) -> MagicMock:
+    stub = MagicMock()
+    stub.multi_conf = multi_conf
+    stub.is_platform_component = is_platform_component
+    stub.config_schema = config_schema
+    return stub
+
+
+def test_populate_platform_component_listed_alone_uses_list() -> None:
+    """Regression: a platform component (sensor) with no `sensor.x` siblings
+    must land as `[]` in config. Previously it was populated as a dict via
+    `schema({})`, which then crashed the sibling `domain.platform` branch
+    when later dependencies tried `config.setdefault('sensor', []).append(...)`.
+    """
+    sensor = _make_component_stub(is_platform_component=True)
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["sensor"],
+        get_component_fn=lambda name: sensor if name == "sensor" else None,
+        register_platform_fn=lambda _: None,
+    )
+
+    assert config["sensor"] == []
+
+
+def test_populate_platform_component_then_platform_entry() -> None:
+    """When `sensor` is processed before `sensor.gpio` (sorted order),
+    the bare-component branch must leave `config['sensor']` as a list so
+    the platform-entry branch can append into it.
+    """
+    sensor = _make_component_stub(is_platform_component=True)
+    gpio = _make_component_stub()  # the bare `gpio` component
+    components: dict[str, object] = {"sensor": sensor, "gpio": gpio}
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["gpio", "sensor", "sensor.gpio"],
+        get_component_fn=components.get,
+        register_platform_fn=lambda _: None,
+    )
+
+    assert config["sensor"] == [{"platform": "gpio"}]
+
+
+def test_populate_multi_conf_component_uses_list() -> None:
+    multi = _make_component_stub(multi_conf=True)
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["multi"],
+        get_component_fn=lambda name: multi if name == "multi" else None,
+        register_platform_fn=lambda _: None,
+    )
+
+    assert config["multi"] == []
+
+
+def test_populate_plain_component_uses_schema_defaults() -> None:
+    schema = MagicMock(return_value={"default_key": 42})
+    plain = _make_component_stub(config_schema=schema)
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["plain"],
+        get_component_fn=lambda name: plain if name == "plain" else None,
+        register_platform_fn=lambda _: None,
+    )
+
+    schema.assert_called_once_with({})
+    assert config["plain"] == {"default_key": 42}
+
+
+def test_populate_plain_component_falls_back_when_schema_raises() -> None:
+    def picky_schema(_):
+        raise ValueError("required field missing")
+
+    plain = _make_component_stub(config_schema=picky_schema)
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["plain"],
+        get_component_fn=lambda name: plain if name == "plain" else None,
+        register_platform_fn=lambda _: None,
+    )
+
+    assert config["plain"] == {}
+
+
+def test_populate_skips_unresolvable_pseudo_components() -> None:
+    """`core` and other names that get_component returns None for are skipped
+    silently without inserting anything into the config.
+    """
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["core"],
+        get_component_fn=lambda _: None,
+        register_platform_fn=lambda _: None,
+    )
+
+    assert config == {}
+
+
+def test_populate_preserves_existing_plain_component_config() -> None:
+    """If a plain component already has a config entry (e.g. from the user's
+    YAML), the schema-defaults branch must not overwrite it.
+    """
+    schema = MagicMock()
+    plain = _make_component_stub(config_schema=schema)
+    config: dict = {"plain": {"user_key": "set_by_user"}}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["plain"],
+        get_component_fn=lambda name: plain if name == "plain" else None,
+        register_platform_fn=lambda _: None,
+    )
+
+    schema.assert_not_called()
+    assert config["plain"] == {"user_key": "set_by_user"}
+
+
+def test_populate_registers_platform_for_platform_entry() -> None:
+    """Each `domain.platform` entry triggers register_platform_fn(domain) so
+    USE_<DOMAIN> defines get emitted later in the build pipeline.
+    """
+    registered: list[str] = []
+    config: dict = {}
+
+    build_helpers.populate_dependency_config(
+        config,
+        ["sensor.gpio", "binary_sensor.gpio"],
+        get_component_fn=lambda _: None,
+        register_platform_fn=registered.append,
+    )
+
+    assert registered == ["sensor", "binary_sensor"]
+    assert config["sensor"] == [{"platform": "gpio"}]
+    assert config["binary_sensor"] == [{"platform": "gpio"}]
diff --git a/tests/unit_tests/analyze_memory/test_source_file_attribution.py b/tests/unit_tests/analyze_memory/test_source_file_attribution.py
new file mode 100644
index 0000000000..2793f41bd0
--- /dev/null
+++ b/tests/unit_tests/analyze_memory/test_source_file_attribution.py
@@ -0,0 +1,43 @@
+"""Tests for source-file-to-component attribution in memory analyzer."""
+
+from unittest.mock import patch
+
+from esphome.analyze_memory import MemoryAnalyzer
+
+
+def _make_analyzer(external_components: set[str] | None = None) -> MemoryAnalyzer:
+    """Create a MemoryAnalyzer with mocked dependencies."""
+    with patch.object(MemoryAnalyzer, "__init__", lambda self, *a, **kw: None):
+        analyzer = MemoryAnalyzer.__new__(MemoryAnalyzer)
+        analyzer.external_components = external_components or set()
+        analyzer._lib_hash_to_name = {}
+    return analyzer
+
+
+def test_source_file_to_component_main_cpp_relative() -> None:
+    """ESPHome-generated src/main.cpp.o (nm path form) attributes to core."""
+    analyzer = _make_analyzer()
+    assert analyzer._source_file_to_component("src/main.cpp.o") == "[esphome]core"
+
+
+def test_source_file_to_component_main_cpp_pioenvs_path() -> None:
+    """Linker map paths like .pioenvs/<env>/src/main.cpp.o attribute to core."""
+    analyzer = _make_analyzer()
+    result = analyzer._source_file_to_component(".pioenvs/drivewaygate/src/main.cpp.o")
+    assert result == "[esphome]core"
+
+
+def test_source_file_to_component_esphome_core() -> None:
+    """Sources under src/esphome/core/ attribute to core."""
+    analyzer = _make_analyzer()
+    result = analyzer._source_file_to_component("src/esphome/core/application.cpp.o")
+    assert result == "[esphome]core"
+
+
+def test_source_file_to_component_known_component() -> None:
+    """Known ESPHome components attribute to their component name."""
+    analyzer = _make_analyzer()
+    result = analyzer._source_file_to_component(
+        "src/esphome/components/wifi/wifi_component.cpp.o"
+    )
+    assert result == "[esphome]wifi"
diff --git a/tests/unit_tests/components/api/__init__.py b/tests/unit_tests/components/api/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/unit_tests/components/api/test_client.py b/tests/unit_tests/components/api/test_client.py
new file mode 100644
index 0000000000..3970d1ce8b
--- /dev/null
+++ b/tests/unit_tests/components/api/test_client.py
@@ -0,0 +1,113 @@
+"""Tests for esphome.components.api.client."""
+
+from __future__ import annotations
+
+from unittest.mock import patch
+
+from esphome.components.api import client as api_client
+from esphome.core import EsphomeError
+
+
+def test_decoder_swallows_esphome_error() -> None:
+    """A failing stack-trace decode must not propagate.
+
+    on_log runs inside an asyncio protocol callback; if EsphomeError
+    escapes, the loop reports "Fatal error: protocol.data_received()
+    call failed.", tears the connection down, and ReconnectLogic loops
+    forever as the device replays the same crash trace on every
+    reconnect.
+    """
+    config = {"esphome": {"name": "test"}}
+    processor = api_client._LogLineProcessor(config, None)
+
+    with patch.object(
+        api_client, "process_stacktrace", side_effect=EsphomeError("no idedata")
+    ) as mock_process:
+        processor.process_line("PC: 0x4010496e")
+
+    assert mock_process.called
+    assert processor.backtrace_state is False
+
+
+def test_decoder_swallows_platform_handler_error() -> None:
+    """The same protection must apply to the platform-specific handler."""
+    config = {"esphome": {"name": "test"}}
+
+    def platform_handler(_config, _line, _state):
+        raise EsphomeError("no idedata")
+
+    processor = api_client._LogLineProcessor(config, platform_handler)
+    processor.process_line("PC: 0x4010496e")
+
+    assert processor.backtrace_state is False
+
+
+def test_decoder_warning_uses_fallback_for_empty_error(caplog) -> None:
+    """_run_idedata raises EsphomeError with no message; the warning
+    must show a useful explanation rather than empty parens.
+    """
+    config = {"esphome": {"name": "test"}}
+    processor = api_client._LogLineProcessor(config, None)
+
+    with patch.object(api_client, "process_stacktrace", side_effect=EsphomeError()):
+        processor.process_line("PC: 0x4010496e")
+
+    warnings = [r.message for r in caplog.records if r.levelname == "WARNING"]
+    assert any("build artifacts not found locally" in m for m in warnings)
+    assert not any("()" in m for m in warnings)
+
+
+def test_decoder_short_circuits_after_failure() -> None:
+    """After one failure, subsequent lines must not retry the decoder.
+
+    _decode_pc shells out to PlatformIO; a crash dump can contain many
+    PC/BT lines and retrying the failing subprocess for each one would
+    stall log streaming.
+    """
+    config = {"esphome": {"name": "test"}}
+    processor = api_client._LogLineProcessor(config, None)
+
+    with patch.object(
+        api_client, "process_stacktrace", side_effect=EsphomeError("no idedata")
+    ) as mock_process:
+        processor.process_line("PC: 0x4010496e")
+        processor.process_line("BT0: 0x4010496e")
+        processor.process_line("BT1: 0x401049aa")
+
+    assert mock_process.call_count == 1
+
+
+def test_decoder_threads_backtrace_state() -> None:
+    """When decoding succeeds, backtrace_state is threaded across calls."""
+    config = {"esphome": {"name": "test"}}
+    processor = api_client._LogLineProcessor(config, None)
+
+    with patch.object(
+        api_client, "process_stacktrace", side_effect=[True, False]
+    ) as mock_process:
+        processor.process_line(">>>stack>>>")
+        assert processor.backtrace_state is True
+        processor.process_line("<<<stack<<<")
+        assert processor.backtrace_state is False
+
+    assert mock_process.call_args_list[0].kwargs == {"backtrace_state": False}
+    assert mock_process.call_args_list[1].kwargs == {"backtrace_state": True}
+
+
+def test_decoder_uses_platform_handler_when_provided() -> None:
+    """The platform handler is preferred over the generic one."""
+    config = {"esphome": {"name": "test"}}
+    calls: list[tuple[object, str, bool]] = []
+
+    def platform_handler(cfg, line, state):
+        calls.append((cfg, line, state))
+        return True
+
+    processor = api_client._LogLineProcessor(config, platform_handler)
+
+    with patch.object(api_client, "process_stacktrace") as mock_generic:
+        processor.process_line("BT0: 0x4010496e")
+
+    assert calls == [(config, "BT0: 0x4010496e", False)]
+    assert mock_generic.called is False
+    assert processor.backtrace_state is True
diff --git a/tests/unit_tests/fixtures/partition_tables/esp_idf_hello_world.bin b/tests/unit_tests/fixtures/partition_tables/esp_idf_hello_world.bin
new file mode 100644
index 0000000000..b8fa03b4b3
Binary files /dev/null and b/tests/unit_tests/fixtures/partition_tables/esp_idf_hello_world.bin differ
diff --git a/tests/unit_tests/fixtures/partition_tables/esphome_dashboard_firmware.bin b/tests/unit_tests/fixtures/partition_tables/esphome_dashboard_firmware.bin
new file mode 100644
index 0000000000..e648fa3270
Binary files /dev/null and b/tests/unit_tests/fixtures/partition_tables/esphome_dashboard_firmware.bin differ
diff --git a/tests/unit_tests/fixtures/partition_tables/esphome_default.bin b/tests/unit_tests/fixtures/partition_tables/esphome_default.bin
new file mode 100644
index 0000000000..d39bf337c9
Binary files /dev/null and b/tests/unit_tests/fixtures/partition_tables/esphome_default.bin differ
diff --git a/tests/unit_tests/test_dashboard_import.py b/tests/unit_tests/test_dashboard_import.py
new file mode 100644
index 0000000000..427bee0f86
--- /dev/null
+++ b/tests/unit_tests/test_dashboard_import.py
@@ -0,0 +1,203 @@
+"""Unit tests for ``esphome.components.dashboard_import.import_config``.
+
+Locks the YAML shape that ``import_config`` materialises on disk for
+adopted factory firmware. Both the legacy dashboard and the new
+device-builder backend (esphome/device-builder) call this function
+during the adoption flow and depend on the output's ``esphome.name``
+/ ``packages:`` keys to route subsequent compile + flash operations.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+import yaml as pyyaml
+
+from esphome.components.dashboard_import import import_config
+
+
+def _load_plain_yaml(path: Path) -> dict:
+    """Load YAML without invoking ESPHome's ``CORE``-aware loader.
+
+    ``esphome.yaml_util.load_yaml`` resolves ``!include`` /
+    ``!secret`` against ``CORE.config_path`` which isn't set in
+    these tests. We're only asserting on plain key/value structure,
+    so ``pyyaml.load`` with a custom loader subclassing
+    ``pyyaml.SafeLoader`` (and empty fallbacks for the secret/include
+    tags) is enough.
+    """
+
+    class _Loader(pyyaml.SafeLoader):
+        pass
+
+    _Loader.add_constructor("!secret", lambda loader, node: f"!secret {node.value}")
+    _Loader.add_constructor("!include", lambda loader, node: f"!include {node.value}")
+
+    return pyyaml.load(path.read_text(encoding="utf-8"), Loader=_Loader)
+
+
+def test_basic_import_writes_expected_yaml_shape(tmp_path: Path) -> None:
+    """A minimal Wi-Fi import emits the substitutions / packages / esphome triad.
+
+    These three top-level blocks are the contract: substitutions
+    holds the device-specific name, packages pulls in the upstream
+    firmware via the import URL, and esphome.name interpolates from
+    substitutions. Anything that depends on this output (frontend
+    config viewer, follow-up edits, version checks) reads those
+    keys directly.
+    """
+    yaml_path = tmp_path / "kitchen.yaml"
+
+    import_config(
+        path=str(yaml_path),
+        name="kitchen",
+        friendly_name="Kitchen",
+        project_name="acme.kitchen-light",
+        import_url="github://acme/firmware/kitchen.yaml@main",
+    )
+
+    assert yaml_path.exists()
+    config = _load_plain_yaml(yaml_path)
+
+    assert config["substitutions"] == {
+        "name": "kitchen",
+        "friendly_name": "Kitchen",
+    }
+    assert config["packages"] == {
+        "acme.kitchen-light": "github://acme/firmware/kitchen.yaml@main"
+    }
+    assert config["esphome"] == {
+        "name": "${name}",
+        "name_add_mac_suffix": False,
+        "friendly_name": "${friendly_name}",
+    }
+
+
+def test_import_appends_wifi_config_when_network_is_wifi(tmp_path: Path) -> None:
+    """Wi-Fi devices get a ``wifi:`` block templated with secrets references.
+
+    Adopted Wi-Fi devices need a ``wifi:`` section so they can
+    actually connect on the user's LAN — the boilerplate references
+    ``!secret wifi_ssid`` / ``!secret wifi_password`` so the
+    user's existing secrets file plugs in. Devices on other
+    networks (Ethernet) shouldn't get the Wi-Fi block.
+    """
+    yaml_path = tmp_path / "kitchen.yaml"
+    import_config(
+        path=str(yaml_path),
+        name="kitchen",
+        friendly_name=None,
+        project_name="acme.kitchen-light",
+        import_url="github://acme/firmware/kitchen.yaml@main",
+    )
+    contents = yaml_path.read_text()
+    assert "wifi:" in contents
+    assert "!secret wifi_ssid" in contents
+    assert "!secret wifi_password" in contents
+
+
+def test_import_omits_wifi_block_for_ethernet_network(tmp_path: Path) -> None:
+    """Ethernet devices get no ``wifi:`` block — caller wires Ethernet separately.
+
+    The ``network`` parameter exists specifically so non-Wi-Fi
+    devices (PoE / Ethernet, etc.) skip the Wi-Fi templating —
+    otherwise their generated YAML would carry an unused ``wifi:``
+    section the user has to clean up by hand.
+    """
+    yaml_path = tmp_path / "olimex-poe.yaml"
+    import_config(
+        path=str(yaml_path),
+        name="olimex-poe",
+        friendly_name=None,
+        project_name="acme.poe-monitor",
+        import_url="github://acme/firmware/poe.yaml@main",
+        network="ethernet",
+    )
+    contents = yaml_path.read_text()
+    assert "wifi:" not in contents
+
+
+def test_import_with_encryption_writes_api_key(tmp_path: Path) -> None:
+    """``encryption=True`` generates a fresh Noise PSK in the api block.
+
+    Used during the adoption flow when the device-builder UI
+    explicitly opts the new device into encrypted API. Each
+    invocation must produce a fresh 32-byte PSK base64-encoded into
+    the YAML; subsequent compiles and the dashboard's encryption
+    indicator both read it from there.
+    """
+    yaml_path_1 = tmp_path / "a.yaml"
+    yaml_path_2 = tmp_path / "b.yaml"
+
+    import_config(
+        path=str(yaml_path_1),
+        name="a",
+        friendly_name=None,
+        project_name="acme.dev",
+        import_url="github://acme/firmware/dev.yaml@main",
+        encryption=True,
+    )
+    import_config(
+        path=str(yaml_path_2),
+        name="b",
+        friendly_name=None,
+        project_name="acme.dev",
+        import_url="github://acme/firmware/dev.yaml@main",
+        encryption=True,
+    )
+
+    config_1 = _load_plain_yaml(yaml_path_1)
+    config_2 = _load_plain_yaml(yaml_path_2)
+    assert "api" in config_1 and "encryption" in config_1["api"]
+    key_1 = config_1["api"]["encryption"]["key"]
+    key_2 = config_2["api"]["encryption"]["key"]
+    # Fresh per-call PSK, not a hardcoded value.
+    assert key_1 != key_2
+    # Base64-encoded 32 bytes → length 44 with one trailing `=`.
+    assert len(key_1) == 44
+
+
+def test_import_without_friendly_name_omits_friendly_substitution(
+    tmp_path: Path,
+) -> None:
+    """``friendly_name=None`` skips the friendly_name substitution.
+
+    Some imported configs don't carry a friendly name. The output
+    shouldn't pretend they do — the substitutions block must omit
+    ``friendly_name`` so the dashboard renders blank rather than
+    the literal substitution token.
+    """
+    yaml_path = tmp_path / "noname.yaml"
+    import_config(
+        path=str(yaml_path),
+        name="noname",
+        friendly_name=None,
+        project_name="acme.dev",
+        import_url="github://acme/firmware/dev.yaml@main",
+    )
+    config = _load_plain_yaml(yaml_path)
+    assert config["substitutions"] == {"name": "noname"}
+    assert "friendly_name" not in config["esphome"]
+
+
+def test_import_refuses_to_overwrite_existing_yaml(tmp_path: Path) -> None:
+    """An already-present file raises rather than clobbering the user's edits.
+
+    Both the legacy dashboard and device-builder rely on the
+    ``FileExistsError`` to surface a "config already exists" message
+    instead of silently destroying user data.
+    """
+    yaml_path = tmp_path / "existing.yaml"
+    yaml_path.write_text("# user's hand-edited config\n", encoding="utf-8")
+
+    with pytest.raises(FileExistsError):
+        import_config(
+            path=str(yaml_path),
+            name="existing",
+            friendly_name=None,
+            project_name="acme.dev",
+            import_url="github://acme/firmware/dev.yaml@main",
+        )
+    # Original content survives unchanged.
+    assert yaml_path.read_text() == "# user's hand-edited config\n"
diff --git a/tests/unit_tests/test_espota2.py b/tests/unit_tests/test_espota2.py
index 20ba4b1f76..2cad1d2ec8 100644
--- a/tests/unit_tests/test_espota2.py
+++ b/tests/unit_tests/test_espota2.py
@@ -185,6 +185,22 @@ def test_receive_exactly_socket_error(mock_socket: Mock) -> None:
             "Error: The OTA partition on the ESP couldn't be found",
         ),
         (espota2.RESPONSE_ERROR_MD5_MISMATCH, "Error: Application MD5 code mismatch"),
+        (
+            espota2.RESPONSE_ERROR_SIGNATURE_INVALID,
+            "Error: Firmware signature verification failed",
+        ),
+        (
+            espota2.RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE,
+            "Error: The requested OTA type is not supported by the device",
+        ),
+        (
+            espota2.RESPONSE_ERROR_PARTITION_TABLE_VERIFY,
+            "Error: The partition table update could not be verified",
+        ),
+        (
+            espota2.RESPONSE_ERROR_PARTITION_TABLE_UPDATE,
+            "Error: An error occurred while updating the partition table",
+        ),
         (espota2.RESPONSE_ERROR_UNKNOWN, "Unknown error from ESP"),
     ],
 )
@@ -270,12 +286,13 @@ def test_perform_ota_successful_md5_auth(
     # Verify magic bytes were sent
     assert mock_socket.sendall.call_args_list[0] == call(bytes(espota2.MAGIC_BYTES))
 
-    # Verify features were sent (compression + SHA256 support)
+    # Verify features were sent (compression + SHA256 support + extended protocol)
     assert mock_socket.sendall.call_args_list[1] == call(
         bytes(
             [
-                espota2.FEATURE_SUPPORTS_COMPRESSION
-                | espota2.FEATURE_SUPPORTS_SHA256_AUTH
+                espota2.CLIENT_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+                | espota2.CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
             ]
         )
     )
@@ -640,12 +657,13 @@ def test_perform_ota_successful_sha256_auth(
     # Verify magic bytes were sent
     assert mock_socket.sendall.call_args_list[0] == call(bytes(espota2.MAGIC_BYTES))
 
-    # Verify features were sent (compression + SHA256 support)
+    # Verify features were sent (compression + SHA256 support + extended protocol)
     assert mock_socket.sendall.call_args_list[1] == call(
         bytes(
             [
-                espota2.FEATURE_SUPPORTS_COMPRESSION
-                | espota2.FEATURE_SUPPORTS_SHA256_AUTH
+                espota2.CLIENT_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+                | espota2.CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
             ]
         )
     )
@@ -699,8 +717,9 @@ def test_perform_ota_sha256_fallback_to_md5(
     assert mock_socket.sendall.call_args_list[1] == call(
         bytes(
             [
-                espota2.FEATURE_SUPPORTS_COMPRESSION
-                | espota2.FEATURE_SUPPORTS_SHA256_AUTH
+                espota2.CLIENT_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+                | espota2.CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
             ]
         )
     )
@@ -765,3 +784,280 @@ def test_perform_ota_version_differences(
 
     # For v2.0, verify more recv calls due to chunk acknowledgments
     assert mock_socket.recv.call_count == 9  # v2.0 has 9 recv calls (includes chunk OK)
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_extended_protocol_app(
+    mock_socket: Mock, mock_file: io.BytesIO
+) -> None:
+    """Test OTA extended protocol app update."""
+    recv_responses = [
+        bytes([espota2.RESPONSE_OK]),  # First byte of version response
+        bytes([espota2.OTA_VERSION_2_0]),  # Version number
+        bytes([espota2.RESPONSE_FEATURE_FLAGS]),  # Device supports extended protocol
+        bytes(
+            [
+                espota2.SERVER_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS
+            ]
+        ),  # Device feature flags
+        bytes([espota2.RESPONSE_AUTH_OK]),  # No auth required
+        bytes([espota2.RESPONSE_UPDATE_PREPARE_OK]),  # Binary size OK
+        bytes([espota2.RESPONSE_BIN_MD5_OK]),  # MD5 checksum OK
+        bytes([espota2.RESPONSE_CHUNK_OK]),  # Chunk OK
+        bytes([espota2.RESPONSE_RECEIVE_OK]),  # Receive OK
+        bytes([espota2.RESPONSE_UPDATE_END_OK]),  # Update end OK
+    ]
+
+    mock_socket.recv.side_effect = recv_responses
+
+    espota2.perform_ota(
+        mock_socket,
+        "testpass",
+        mock_file,
+        "test.bin",
+        espota2.OTA_TYPE_UPDATE_APP,
+    )
+
+    # Verify magic bytes were sent
+    assert mock_socket.sendall.call_args_list[0] == call(bytes(espota2.MAGIC_BYTES))
+
+    # Verify features were sent (compression + SHA256 support + extended protocol)
+    assert mock_socket.sendall.call_args_list[1] == call(
+        bytes(
+            [
+                espota2.CLIENT_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+                | espota2.CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
+            ]
+        )
+    )
+
+    # Verify ota type was sent
+    assert mock_socket.sendall.call_args_list[2] == call(
+        bytes([espota2.OTA_TYPE_UPDATE_APP])
+    )
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_successful_partition_table(
+    mock_socket: Mock, mock_file: io.BytesIO
+) -> None:
+    """Test OTA partition table update.
+
+    The mocked server advertises both COMPRESSION and PARTITION_ACCESS to exercise
+    the full extended-protocol negotiation path. Real IDFOTABackend devices return
+    ``supports_compression() == false`` and never set the COMPRESSION flag for a
+    partition-table OTA; the flag here is intentional protocol-coverage, not a
+    description of on-device behaviour.
+    """
+    recv_responses = [
+        bytes([espota2.RESPONSE_OK]),  # First byte of version response
+        bytes([espota2.OTA_VERSION_2_0]),  # Version number
+        bytes([espota2.RESPONSE_FEATURE_FLAGS]),  # Device supports extended protocol
+        bytes(
+            [
+                espota2.SERVER_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS
+            ]
+        ),  # Device feature flags (compression flag is unrealistic; see docstring)
+        bytes([espota2.RESPONSE_AUTH_OK]),  # No auth required
+        bytes([espota2.RESPONSE_UPDATE_PREPARE_OK]),  # Binary size OK
+        bytes([espota2.RESPONSE_BIN_MD5_OK]),  # MD5 checksum OK
+        bytes([espota2.RESPONSE_CHUNK_OK]),  # Chunk OK
+        bytes([espota2.RESPONSE_RECEIVE_OK]),  # Receive OK
+        bytes([espota2.RESPONSE_UPDATE_END_OK]),  # Update end OK
+    ]
+
+    mock_socket.recv.side_effect = recv_responses
+
+    espota2.perform_ota(
+        mock_socket,
+        "testpass",
+        mock_file,
+        "partitions.bin",
+        espota2.OTA_TYPE_UPDATE_PARTITION_TABLE,
+    )
+
+    # Verify magic bytes were sent
+    assert mock_socket.sendall.call_args_list[0] == call(bytes(espota2.MAGIC_BYTES))
+
+    # Verify features were sent (compression + SHA256 support + extended protocol)
+    assert mock_socket.sendall.call_args_list[1] == call(
+        bytes(
+            [
+                espota2.CLIENT_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.CLIENT_FEATURE_SUPPORTS_SHA256_AUTH
+                | espota2.CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL
+            ]
+        )
+    )
+
+    # Verify ota type was sent
+    assert mock_socket.sendall.call_args_list[2] == call(
+        bytes([espota2.OTA_TYPE_UPDATE_PARTITION_TABLE])
+    )
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_device_rejects_with_unsupported_ota_type(
+    mock_socket: Mock, mock_file: io.BytesIO
+) -> None:
+    """End-to-end: device returns 0x8E after the size byte; perform_ota must
+    surface the human-readable 'unsupported OTA type' error from the lookup
+    table in check_error()."""
+    recv_responses = [
+        bytes([espota2.RESPONSE_OK]),  # First byte of version response
+        bytes([espota2.OTA_VERSION_2_0]),  # Version number
+        bytes([espota2.RESPONSE_FEATURE_FLAGS]),  # Extended protocol marker
+        bytes(
+            [
+                espota2.SERVER_FEATURE_SUPPORTS_COMPRESSION
+                | espota2.SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS
+            ]
+        ),  # Feature flags
+        bytes([espota2.RESPONSE_AUTH_OK]),  # No auth required
+        bytes([espota2.RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE]),  # Reject at size step
+    ]
+
+    mock_socket.recv.side_effect = recv_responses
+
+    with pytest.raises(
+        espota2.OTAError,
+        match="The requested OTA type is not supported by the device",
+    ):
+        espota2.perform_ota(
+            mock_socket,
+            "testpass",
+            mock_file,
+            "test.bin",
+            espota2.OTA_TYPE_UPDATE_APP,
+        )
+
+    # Verify the client did send the OTA type byte before the size step
+    assert mock_socket.sendall.call_args_list[2] == call(
+        bytes([espota2.OTA_TYPE_UPDATE_APP])
+    )
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_unsupported_type_rejected_early(
+    mock_socket: Mock, mock_file: io.BytesIO
+) -> None:
+    """ota_type values not in _SUPPORTED_OTA_TYPES are rejected before any I/O."""
+    with pytest.raises(espota2.OTAError, match="Unsupported OTA type 0xFF"):
+        espota2.perform_ota(
+            mock_socket,
+            "testpass",
+            mock_file,
+            "test.bin",
+            0xFF,
+        )
+    # No bytes should have been transmitted to the device.
+    mock_socket.sendall.assert_not_called()
+
+
+@pytest.mark.parametrize("bad_type", [-1, 256, 0x10000, "app", None, 1.5])
+def test_perform_ota_rejects_out_of_range_type(
+    mock_socket: Mock, mock_file: io.BytesIO, bad_type: object
+) -> None:
+    """Out-of-range or non-int ota_type must raise OTAError, not ValueError."""
+    with pytest.raises(espota2.OTAError, match="Invalid ota_type"):
+        espota2.perform_ota(
+            mock_socket,
+            "testpass",
+            mock_file,
+            "test.bin",
+            bad_type,  # type: ignore[arg-type]
+        )
+    mock_socket.sendall.assert_not_called()
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_non_app_type_requires_extended_protocol(
+    mock_socket: Mock, mock_file: io.BytesIO, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Non-app OTA type must fail when device only supports the legacy protocol."""
+    monkeypatch.setattr(
+        espota2,
+        "_SUPPORTED_OTA_TYPES",
+        frozenset({espota2.OTA_TYPE_UPDATE_APP, 0xFF}),
+    )
+    recv_responses = [
+        bytes([espota2.RESPONSE_OK]),  # First byte of version response
+        bytes([espota2.OTA_VERSION_2_0]),  # Version number
+        bytes([espota2.RESPONSE_HEADER_OK]),  # Legacy single-byte feature ack
+    ]
+
+    mock_socket.recv.side_effect = recv_responses
+
+    with pytest.raises(
+        espota2.OTAError, match="Device does not support extended OTA protocol"
+    ):
+        espota2.perform_ota(
+            mock_socket,
+            "testpass",
+            mock_file,
+            "test.bin",
+            0xFF,
+        )
+
+
+@pytest.mark.usefixtures("mock_time")
+def test_perform_ota_non_app_type_requires_partition_access(
+    mock_socket: Mock, mock_file: io.BytesIO, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Non-app OTA type must fail when device advertises extended protocol but
+    not the partition-access feature."""
+    monkeypatch.setattr(
+        espota2,
+        "_SUPPORTED_OTA_TYPES",
+        frozenset({espota2.OTA_TYPE_UPDATE_APP, 0xFF}),
+    )
+    recv_responses = [
+        bytes([espota2.RESPONSE_OK]),  # First byte of version response
+        bytes([espota2.OTA_VERSION_2_0]),  # Version number
+        bytes([espota2.RESPONSE_FEATURE_FLAGS]),  # Extended protocol marker
+        bytes(
+            [espota2.SERVER_FEATURE_SUPPORTS_COMPRESSION]
+        ),  # Compression only, no partition access
+    ]
+
+    mock_socket.recv.side_effect = recv_responses
+
+    with pytest.raises(
+        espota2.OTAError, match="Device does not support partition access"
+    ):
+        espota2.perform_ota(
+            mock_socket,
+            "testpass",
+            mock_file,
+            "test.bin",
+            0xFF,
+        )
+
+
+def test_check_error_detects_errors_when_expect_is_none() -> None:
+    """check_error must surface device error bytes even when expect is None.
+
+    Regression test: previously, receive_exactly(..., expect=None) calls (used
+    during feature negotiation and nonce reads) silently passed error bytes
+    through, turning clean device errors into confusing later failures.
+    """
+    with pytest.raises(espota2.OTAError, match="Error: Authentication invalid"):
+        espota2.check_error([espota2.RESPONSE_ERROR_AUTH_INVALID], None)
+
+
+def test_check_error_detects_empty_when_expect_is_none() -> None:
+    """Empty data with expect=None must still raise (connection closed)."""
+    with pytest.raises(
+        espota2.OTAError, match="Device closed connection without responding"
+    ):
+        espota2.check_error([], None)
+
+
+def test_check_error_passes_non_error_when_expect_is_none() -> None:
+    """Non-error bytes with expect=None must pass through silently."""
+    espota2.check_error([espota2.RESPONSE_OK], None)
+    espota2.check_error([espota2.RESPONSE_HEADER_OK], None)
+    espota2.check_error([espota2.RESPONSE_FEATURE_FLAGS], None)
diff --git a/tests/unit_tests/test_external_files.py b/tests/unit_tests/test_external_files.py
index 4b0826db04..64ef149581 100644
--- a/tests/unit_tests/test_external_files.py
+++ b/tests/unit_tests/test_external_files.py
@@ -1,5 +1,6 @@
 """Tests for external_files.py functions."""
 
+import os
 from pathlib import Path
 import time
 from unittest.mock import MagicMock, patch
@@ -8,8 +9,73 @@ import pytest
 import requests
 
 from esphome import external_files
-from esphome.config_validation import Invalid
-from esphome.core import CORE, TimePeriod
+from esphome.config_validation import Invalid, MultipleInvalid
+from esphome.core import CORE, EsphomeError, TimePeriod
+
+
+def _seed_etag(cache_file: Path, etag: str) -> Path:
+    """Write an ETag sidecar with its mtime synced to the cache file's mtime,
+    matching the invariant that `_write_etag` enforces in production.
+    """
+    sidecar = external_files._etag_sidecar_path(cache_file)
+    sidecar.write_text(etag)
+    file_mtime = int(cache_file.stat().st_mtime)
+    os.utime(sidecar, (file_mtime, file_mtime))
+    return sidecar
+
+
+@pytest.fixture
+def mock_requests_head() -> MagicMock:
+    """Patch `external_files.requests.head` so the conditional HEAD-request
+    validator can be tested without doing real HTTP.
+    """
+    with patch("esphome.external_files.requests.head") as m:
+        yield m
+
+
+@pytest.fixture
+def mock_requests_get() -> MagicMock:
+    """Patch `external_files.requests.get` so the download path can be
+    tested without doing real HTTP.
+    """
+    with patch("esphome.external_files.requests.get") as m:
+        yield m
+
+
+@pytest.fixture
+def mock_has_remote_file_changed() -> MagicMock:
+    """Patch `external_files.has_remote_file_changed` so download tests can
+    control the conditional check independently from the GET path.
+    """
+    with patch("esphome.external_files.has_remote_file_changed") as m:
+        yield m
+
+
+@pytest.fixture
+def mock_write_file() -> MagicMock:
+    """Patch `external_files.write_file` so atomic-write failures can be
+    injected without involving the real filesystem helper.
+    """
+    with patch("esphome.external_files.write_file") as m:
+        yield m
+
+
+@pytest.fixture
+def mock_download_content() -> MagicMock:
+    """Patch `external_files.download_content` for tests that exercise the
+    parallel batch helper without doing real I/O.
+    """
+    with patch("esphome.external_files.download_content") as m:
+        yield m
+
+
+@pytest.fixture
+def mock_download_content_many() -> MagicMock:
+    """Patch `external_files.download_content_many` for tests that exercise
+    the URL-collection helper without dispatching to the thread pool.
+    """
+    with patch("esphome.external_files.download_content_many") as m:
+        yield m
 
 
 def test_compute_local_file_dir(setup_core: Path) -> None:
@@ -88,9 +154,8 @@ def test_is_file_recent_with_zero_refresh(setup_core: Path) -> None:
         assert result is False
 
 
-@patch("esphome.external_files.requests.head")
 def test_has_remote_file_changed_not_modified(
-    mock_head: MagicMock, setup_core: Path
+    mock_requests_head: MagicMock, setup_core: Path
 ) -> None:
     """Test has_remote_file_changed returns False when file not modified."""
     test_file = setup_core / "cached.txt"
@@ -98,23 +163,23 @@ def test_has_remote_file_changed_not_modified(
 
     mock_response = MagicMock()
     mock_response.status_code = 304
-    mock_head.return_value = mock_response
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
 
     url = "https://example.com/file.txt"
     result = external_files.has_remote_file_changed(url, test_file)
 
     assert result is False
-    mock_head.assert_called_once()
+    mock_requests_head.assert_called_once()
 
-    call_args = mock_head.call_args
+    call_args = mock_requests_head.call_args
     headers = call_args[1]["headers"]
     assert external_files.IF_MODIFIED_SINCE in headers
     assert external_files.CACHE_CONTROL in headers
 
 
-@patch("esphome.external_files.requests.head")
 def test_has_remote_file_changed_modified(
-    mock_head: MagicMock, setup_core: Path
+    mock_requests_head: MagicMock, setup_core: Path
 ) -> None:
     """Test has_remote_file_changed returns True when file modified."""
     test_file = setup_core / "cached.txt"
@@ -122,7 +187,8 @@ def test_has_remote_file_changed_modified(
 
     mock_response = MagicMock()
     mock_response.status_code = 200
-    mock_head.return_value = mock_response
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
 
     url = "https://example.com/file.txt"
     result = external_files.has_remote_file_changed(url, test_file)
@@ -140,15 +206,16 @@ def test_has_remote_file_changed_no_local_file(setup_core: Path) -> None:
     assert result is True
 
 
-@patch("esphome.external_files.requests.head")
 def test_has_remote_file_changed_network_error(
-    mock_head: MagicMock, setup_core: Path
+    mock_requests_head: MagicMock, setup_core: Path
 ) -> None:
     """Test has_remote_file_changed returns False on network error when file is cached."""
     test_file = setup_core / "cached.txt"
     test_file.write_text("cached content")
 
-    mock_head.side_effect = requests.exceptions.RequestException("Network error")
+    mock_requests_head.side_effect = requests.exceptions.RequestException(
+        "Network error"
+    )
 
     url = "https://example.com/file.txt"
     result = external_files.has_remote_file_changed(url, test_file)
@@ -156,9 +223,8 @@ def test_has_remote_file_changed_network_error(
     assert result is False
 
 
-@patch("esphome.external_files.requests.head")
 def test_has_remote_file_changed_timeout(
-    mock_head: MagicMock, setup_core: Path
+    mock_requests_head: MagicMock, setup_core: Path
 ) -> None:
     """Test has_remote_file_changed respects timeout."""
     test_file = setup_core / "cached.txt"
@@ -166,15 +232,176 @@ def test_has_remote_file_changed_timeout(
 
     mock_response = MagicMock()
     mock_response.status_code = 304
-    mock_head.return_value = mock_response
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
 
     url = "https://example.com/file.txt"
     external_files.has_remote_file_changed(url, test_file)
 
-    call_args = mock_head.call_args
+    call_args = mock_requests_head.call_args
     assert call_args[1]["timeout"] == external_files.NETWORK_TIMEOUT
 
 
+def test_has_remote_file_changed_uses_etag(
+    mock_requests_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed sends If-None-Match when ETag is cached."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+    _seed_etag(test_file, '"abc123"')
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    result = external_files.has_remote_file_changed(url, test_file)
+
+    assert result is False
+    headers = mock_requests_head.call_args[1]["headers"]
+    assert headers[external_files.IF_NONE_MATCH] == '"abc123"'
+
+
+def test_has_remote_file_changed_no_etag_no_if_none_match(
+    mock_requests_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed omits If-None-Match when no ETag is cached."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    external_files.has_remote_file_changed(url, test_file)
+
+    headers = mock_requests_head.call_args[1]["headers"]
+    assert external_files.IF_NONE_MATCH not in headers
+
+
+def test_has_remote_file_changed_refreshes_etag_on_304(
+    mock_requests_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed updates the cached ETag when the 304 sends a new one."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+    _seed_etag(test_file, '"old"')
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_response.headers = {external_files.ETAG: '"new"'}
+    mock_requests_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    external_files.has_remote_file_changed(url, test_file)
+
+    assert external_files._etag_sidecar_path(test_file).read_text() == '"new"'
+
+
+def test_has_remote_file_changed_ignores_etag_when_mtime_diverges(
+    mock_requests_head: MagicMock, setup_core: Path
+) -> None:
+    """If the cache file was edited out-of-band (mtime no longer matches the
+    sidecar's), the cached ETag must not be used -- it no longer describes the
+    bytes on disk.
+    """
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+    sidecar = _seed_etag(test_file, '"abc123"')
+
+    # Simulate an out-of-band edit to the cache file -- mtime advances by a
+    # full second (so it diverges at whole-second resolution) but the sidecar
+    # is left untouched, so the recorded ETag is now stale.
+    file_stat = test_file.stat()
+    os.utime(test_file, (file_stat.st_atime, file_stat.st_mtime + 1))
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_response.headers = {}
+    mock_requests_head.return_value = mock_response
+
+    external_files.has_remote_file_changed("https://example.com/file.txt", test_file)
+
+    headers = mock_requests_head.call_args[1]["headers"]
+    assert external_files.IF_NONE_MATCH not in headers
+    # Stale sidecar should be removed so future calls don't keep paying the
+    # mtime-comparison cost on a known-bad sidecar.
+    assert not sidecar.exists()
+
+
+def test_download_content_pins_etag_mtime_to_file_mtime(
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
+) -> None:
+    """After a successful download, the sidecar's mtime must equal the cache
+    file's mtime so `_read_etag` accepts it on the next call.
+    """
+    test_file = setup_core / "fresh.txt"
+    mock_has_remote_file_changed.return_value = True
+    mock_response = MagicMock()
+    mock_response.content = b"fresh content"
+    mock_response.headers = {external_files.ETAG: '"deadbeef"'}
+    mock_response.raise_for_status = MagicMock()
+    mock_requests_get.return_value = mock_response
+
+    external_files.download_content("https://example.com/file.txt", test_file)
+
+    sidecar = external_files._etag_sidecar_path(test_file)
+    assert int(sidecar.stat().st_mtime) == int(test_file.stat().st_mtime)
+
+
+def test_write_etag_swallows_write_file_failure(
+    mock_write_file: MagicMock, setup_core: Path, caplog: pytest.LogCaptureFixture
+) -> None:
+    """If `write_file` raises, _write_etag must not propagate -- ETag
+    persistence is best-effort and a failure here must not abort the
+    surrounding download.
+    """
+    cache_file = setup_core / "cached.txt"
+    cache_file.write_text("cached content")
+    mock_write_file.side_effect = EsphomeError("disk full")
+
+    with caplog.at_level("DEBUG", logger="esphome.external_files"):
+        external_files._write_etag(cache_file, '"abc123"')
+
+    assert "Could not save ETag" in caplog.text
+    # Sidecar wasn't created, since write_file was mocked to fail before
+    # reaching the os.utime step.
+    assert not external_files._etag_sidecar_path(cache_file).exists()
+
+
+def test_write_etag_swallows_utime_failure(
+    setup_core: Path, caplog: pytest.LogCaptureFixture
+) -> None:
+    """If `os.utime` raises while pinning the sidecar's mtime, _write_etag
+    must not propagate. The sidecar is still written; if its mtime later
+    fails to match the cache file, `_read_etag` will discard it on next
+    read.
+    """
+    cache_file = setup_core / "cached.txt"
+    cache_file.write_text("cached content")
+
+    with (
+        patch(
+            "esphome.external_files.os.utime",
+            side_effect=PermissionError("nope"),
+        ),
+        caplog.at_level("DEBUG", logger="esphome.external_files"),
+    ):
+        external_files._write_etag(cache_file, '"abc123"')
+
+    assert "Could not sync ETag sidecar mtime" in caplog.text
+    # write_file succeeded, so the sidecar exists with the new value even
+    # though we couldn't pin its mtime.
+    sidecar = external_files._etag_sidecar_path(cache_file)
+    assert sidecar.exists()
+    assert sidecar.read_text() == '"abc123"'
+
+
 def test_compute_local_file_dir_creates_parent_dirs(setup_core: Path) -> None:
     """Test compute_local_file_dir creates parent directories."""
     domain = "level1/level2/level3/level4"
@@ -200,10 +427,10 @@ def test_is_file_recent_handles_float_seconds(setup_core: Path) -> None:
     assert result is True
 
 
-@patch("esphome.external_files.requests.get")
-@patch("esphome.external_files.has_remote_file_changed")
 def test_download_content_with_network_error_uses_cache(
-    mock_has_changed: MagicMock, mock_get: MagicMock, setup_core: Path
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
 ) -> None:
     """Test download_content uses cached file when network fails."""
     test_file = setup_core / "cached.txt"
@@ -211,8 +438,10 @@ def test_download_content_with_network_error_uses_cache(
     test_file.write_bytes(cached_content)
 
     # Simulate file has changed, so it tries to download
-    mock_has_changed.return_value = True
-    mock_get.side_effect = requests.exceptions.RequestException("Network error")
+    mock_has_remote_file_changed.return_value = True
+    mock_requests_get.side_effect = requests.exceptions.RequestException(
+        "Network error"
+    )
 
     url = "https://example.com/file.txt"
     result = external_files.download_content(url, test_file)
@@ -220,17 +449,19 @@ def test_download_content_with_network_error_uses_cache(
     assert result == cached_content
 
 
-@patch("esphome.external_files.requests.get")
-@patch("esphome.external_files.has_remote_file_changed")
 def test_download_content_with_network_error_no_cache_fails(
-    mock_has_changed: MagicMock, mock_get: MagicMock, setup_core: Path
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
 ) -> None:
     """Test download_content raises error when network fails and no cache exists."""
     test_file = setup_core / "nonexistent.txt"
 
     # Simulate file has changed (doesn't exist), so it tries to download
-    mock_has_changed.return_value = True
-    mock_get.side_effect = requests.exceptions.RequestException("Network error")
+    mock_has_remote_file_changed.return_value = True
+    mock_requests_get.side_effect = requests.exceptions.RequestException(
+        "Network error"
+    )
 
     url = "https://example.com/file.txt"
 
@@ -238,11 +469,72 @@ def test_download_content_with_network_error_no_cache_fails(
         external_files.download_content(url, test_file)
 
 
-@patch("esphome.external_files.requests.get")
-@patch("esphome.external_files.has_remote_file_changed")
+class _BodyReadErrorResponse:
+    """Stand-in for `requests.Response` whose `.content` raises on access.
+
+    A small dedicated stub avoids mutating `MagicMock`'s class with a
+    `property` (which would leak across every other MagicMock-based test
+    in this file).
+    """
+
+    def __init__(self, exc: Exception) -> None:
+        self._exc = exc
+        self.headers: dict[str, str] = {}
+
+    def raise_for_status(self) -> None:
+        return None
+
+    @property
+    def content(self) -> bytes:
+        raise self._exc
+
+
+def test_download_content_with_body_read_error_uses_cache(
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
+) -> None:
+    """Body-read errors (chunked-decode/gzip-decode/mid-stream connection
+    drop) raise RequestException subclasses on `.content` access, not from
+    `requests.get` itself. They must follow the same fall-back-to-cache
+    path as a connect-time failure.
+    """
+    test_file = setup_core / "cached.txt"
+    cached_content = b"cached content"
+    test_file.write_bytes(cached_content)
+
+    mock_has_remote_file_changed.return_value = True
+    mock_requests_get.return_value = _BodyReadErrorResponse(
+        requests.exceptions.ChunkedEncodingError("body truncated")
+    )
+
+    result = external_files.download_content("https://example.com/file.txt", test_file)
+
+    assert result == cached_content
+
+
+def test_download_content_with_body_read_error_no_cache_fails(
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
+) -> None:
+    """A body-read failure with no cache available must surface as a
+    cv.Invalid, same as a connect-time failure with no cache.
+    """
+    test_file = setup_core / "nonexistent.txt"
+
+    mock_has_remote_file_changed.return_value = True
+    mock_requests_get.return_value = _BodyReadErrorResponse(
+        requests.exceptions.ChunkedEncodingError("body truncated")
+    )
+
+    with pytest.raises(Invalid, match="Could not download from.*body truncated"):
+        external_files.download_content("https://example.com/file.txt", test_file)
+
+
 def test_download_content_skip_external_update_uses_cache(
-    mock_has_changed: MagicMock,
-    mock_get: MagicMock,
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
     setup_core: Path,
 ) -> None:
     """Test download_content skips network checks when CORE.skip_external_update is set."""
@@ -255,26 +547,25 @@ def test_download_content_skip_external_update_uses_cache(
     result = external_files.download_content(url, test_file)
 
     assert result == cached_content
-    mock_has_changed.assert_not_called()
-    mock_get.assert_not_called()
+    mock_has_remote_file_changed.assert_not_called()
+    mock_requests_get.assert_not_called()
 
 
-@patch("esphome.external_files.requests.get")
-@patch("esphome.external_files.has_remote_file_changed")
 def test_download_content_skip_external_update_downloads_when_missing(
-    mock_has_changed: MagicMock,
-    mock_get: MagicMock,
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
     setup_core: Path,
 ) -> None:
     """Test download_content still downloads when file is missing, even with skip_external_update."""
     test_file = setup_core / "missing.txt"
     new_content = b"fresh content"
 
-    mock_has_changed.return_value = True
+    mock_has_remote_file_changed.return_value = True
     mock_response = MagicMock()
     mock_response.content = new_content
+    mock_response.headers = {}
     mock_response.raise_for_status = MagicMock()
-    mock_get.return_value = mock_response
+    mock_requests_get.return_value = mock_response
 
     CORE.skip_external_update = True
     url = "https://example.com/file.txt"
@@ -282,3 +573,229 @@ def test_download_content_skip_external_update_downloads_when_missing(
 
     assert result == new_content
     assert test_file.read_bytes() == new_content
+
+
+def test_download_content_many_empty_is_noop(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """Empty input shouldn't spin up a thread pool or call download_content."""
+    external_files.download_content_many([])
+    mock_download_content.assert_not_called()
+
+
+def test_download_content_many_single_item_avoids_pool(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """A single item should be downloaded inline (no thread pool overhead)."""
+    item = ("https://example.com/file.txt", setup_core / "f.txt")
+    external_files.download_content_many([item])
+    mock_download_content.assert_called_once_with(
+        item[0], item[1], external_files.NETWORK_TIMEOUT
+    )
+
+
+def test_download_content_many_runs_in_parallel(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """Multiple items should run concurrently — total wall time ≈ max latency."""
+    import threading
+
+    barrier = threading.Barrier(3)
+
+    def slow_download(url: str, path: Path, timeout: int) -> bytes:
+        # If calls were serial this would deadlock (third caller never arrives
+        # while the first is blocked at the barrier).
+        barrier.wait(timeout=2.0)
+        return b""
+
+    mock_download_content.side_effect = slow_download
+    items = [
+        ("https://example.com/a", setup_core / "a"),
+        ("https://example.com/b", setup_core / "b"),
+        ("https://example.com/c", setup_core / "c"),
+    ]
+    external_files.download_content_many(items, max_workers=4)
+    assert mock_download_content.call_count == 3
+
+
+def test_download_content_many_propagates_single_error(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """A single failing worker should raise its `Invalid` directly, not wrap
+    it in a `MultipleInvalid` that the caller would have to unpack.
+    """
+
+    def fake_download(url: str, path: Path, timeout: int) -> bytes:
+        if url.endswith("bad"):
+            raise Invalid(f"could not download {url}")
+        return b""
+
+    mock_download_content.side_effect = fake_download
+    items = [
+        ("https://example.com/ok", setup_core / "ok"),
+        ("https://example.com/bad", setup_core / "bad"),
+    ]
+    with pytest.raises(Invalid, match="could not download") as exc_info:
+        external_files.download_content_many(items)
+    assert not isinstance(exc_info.value, MultipleInvalid)
+
+
+def test_download_content_many_aggregates_multiple_errors(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """Every failing worker should be reported in a single MultipleInvalid so
+    the user sees all broken URLs in one validation pass instead of fixing
+    them one network round-trip at a time.
+    """
+
+    def fake_download(url: str, path: Path, timeout: int) -> bytes:
+        if url.endswith("ok"):
+            return b""
+        raise Invalid(f"could not download {url}")
+
+    mock_download_content.side_effect = fake_download
+    items = [
+        ("https://example.com/ok", setup_core / "ok"),
+        ("https://example.com/bad1", setup_core / "bad1"),
+        ("https://example.com/bad2", setup_core / "bad2"),
+    ]
+    with pytest.raises(MultipleInvalid) as exc_info:
+        external_files.download_content_many(items)
+    messages = {str(e) for e in exc_info.value.errors}
+    assert messages == {
+        "could not download https://example.com/bad1",
+        "could not download https://example.com/bad2",
+    }
+
+
+def test_download_content_many_dedupes_by_path(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """Two items pointing at the same cache path must collapse to one
+    download -- otherwise concurrent writes race on the same file. Which
+    URL wins doesn't matter (in practice duplicate paths only arise when
+    the URL is duplicated), so we only assert the call count and path.
+    """
+    path = setup_core / "shared"
+    items = [
+        ("https://example.com/a", path),
+        ("https://example.com/b", path),
+        ("https://example.com/a", path),
+    ]
+    external_files.download_content_many(items)
+    assert mock_download_content.call_count == 1
+    args, _ = mock_download_content.call_args
+    assert args[1] == path
+
+
+def test_download_content_many_clamps_invalid_max_workers(
+    mock_download_content: MagicMock, setup_core: Path
+) -> None:
+    """`max_workers <= 0` must not raise from ThreadPoolExecutor; it should
+    be clamped up to at least 1 worker.
+    """
+    items = [
+        ("https://example.com/a", setup_core / "a"),
+        ("https://example.com/b", setup_core / "b"),
+    ]
+    external_files.download_content_many(items, max_workers=0)
+    assert mock_download_content.call_count == 2
+
+
+def test_download_web_files_in_config_filters_and_dispatches(
+    mock_download_content_many: MagicMock, setup_core: Path
+) -> None:
+    """Only `file.type == "web"` entries should be forwarded to
+    download_content_many, and the unmodified config should be returned so
+    the helper can sit in a `cv.All(...)` chain.
+    """
+
+    def path_for(file_dict: dict) -> Path:
+        return setup_core / file_dict["url"].rsplit("/", 1)[-1]
+
+    config = [
+        {"file": {"type": "web", "url": "https://example.com/a"}},
+        {"file": {"type": "local", "path": "/tmp/b"}},
+        {"file": {"type": "web", "url": "https://example.com/c"}},
+        {},  # no `file` key at all
+    ]
+    result = external_files.download_web_files_in_config(config, path_for)
+
+    assert result is config
+    mock_download_content_many.assert_called_once()
+    assert list(mock_download_content_many.call_args[0][0]) == [
+        ("https://example.com/a", setup_core / "a"),
+        ("https://example.com/c", setup_core / "c"),
+    ]
+
+
+def test_download_web_files_in_config_no_web_entries(
+    mock_download_content_many: MagicMock, setup_core: Path
+) -> None:
+    """A config with no web entries should still call through to
+    download_content_many (which is itself a no-op for empty input) so the
+    behavior stays consistent.
+    """
+    config = [{"file": {"type": "local", "path": "/tmp/a"}}]
+    external_files.download_web_files_in_config(config, lambda _: setup_core / "x")
+    mock_download_content_many.assert_called_once()
+    assert list(mock_download_content_many.call_args[0][0]) == []
+
+
+def test_download_content_saves_etag(
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    setup_core: Path,
+) -> None:
+    """Test download_content writes the ETag sidecar after a successful download."""
+    test_file = setup_core / "fresh.txt"
+    new_content = b"fresh content"
+
+    mock_has_remote_file_changed.return_value = True
+    mock_response = MagicMock()
+    mock_response.content = new_content
+    mock_response.headers = {external_files.ETAG: '"deadbeef"'}
+    mock_response.raise_for_status = MagicMock()
+    mock_requests_get.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    external_files.download_content(url, test_file)
+
+    assert external_files._etag_sidecar_path(test_file).read_text() == '"deadbeef"'
+
+
+def test_download_content_atomic_write_no_partial_on_failure(
+    mock_has_remote_file_changed: MagicMock,
+    mock_requests_get: MagicMock,
+    mock_write_file: MagicMock,
+    setup_core: Path,
+) -> None:
+    """If `write_file` (the atomic-write helper) fails, the existing cache
+    file must remain untouched and no temp files may be left behind. Patching
+    `write_file` directly exercises the atomic-rename path -- a failure inside
+    `write_file` is the only reason the rename wouldn't have happened.
+    """
+    from esphome.core import EsphomeError
+
+    test_file = setup_core / "cached.txt"
+    original_content = b"original content"
+    test_file.write_bytes(original_content)
+
+    mock_has_remote_file_changed.return_value = True
+    mock_response = MagicMock()
+    mock_response.content = b"new content"
+    mock_response.headers = {}
+    mock_response.raise_for_status = MagicMock()
+    mock_requests_get.return_value = mock_response
+
+    mock_write_file.side_effect = EsphomeError("disk full")
+
+    with pytest.raises(EsphomeError, match="disk full"):
+        external_files.download_content("https://example.com/file.txt", test_file)
+
+    # Original file is untouched -- write_file aborted before its rename step.
+    assert test_file.read_bytes() == original_content
+    # write_file is responsible for cleaning its own temp files; nothing leaks
+    # into the cache directory either way.
+    leftover_tmps = list(setup_core.glob("tmp*"))
+    assert leftover_tmps == []
diff --git a/tests/unit_tests/test_git.py b/tests/unit_tests/test_git.py
index dd7d26cb71..eab6bfc2cb 100644
--- a/tests/unit_tests/test_git.py
+++ b/tests/unit_tests/test_git.py
@@ -811,3 +811,193 @@ def test_clone_or_update_stale_clone_is_retried_after_cleanup(
     assert repo_dir.exists()
     assert call_count["clone"] == 2
     assert call_count["fetch"] == 2
+
+
+def test_clone_with_ref_uses_shallow_fetch(
+    tmp_path: Path, mock_run_git_command: Mock
+) -> None:
+    """Clone with a ref should use --depth=1 on both clone and fetch."""
+    CORE.config_path = tmp_path / "test.yaml"
+
+    url = "https://github.com/test/repo"
+    ref = "pull/123/head"
+    domain = "test"
+    repo_dir = _compute_repo_dir(url, ref, domain)
+
+    def git_command_side_effect(
+        cmd: list[str], cwd: str | None = None, **kwargs: Any
+    ) -> str:
+        if _get_git_command_type(cmd) == "clone":
+            repo_dir.mkdir(parents=True, exist_ok=True)
+            (repo_dir / ".git").mkdir(exist_ok=True)
+        return ""
+
+    mock_run_git_command.side_effect = git_command_side_effect
+
+    git.clone_or_update(url=url, ref=ref, refresh=None, domain=domain)
+
+    call_list = mock_run_git_command.call_args_list
+
+    clone_calls = [c for c in call_list if "clone" in c[0][0]]
+    assert len(clone_calls) == 1
+    assert "--depth=1" in clone_calls[0][0][0]
+
+    fetch_calls = [c for c in call_list if "fetch" in c[0][0]]
+    assert len(fetch_calls) == 1
+    assert "--depth=1" in fetch_calls[0][0][0]
+    # Ref must still be passed so the requested commit/branch is fetched.
+    assert ref in fetch_calls[0][0][0]
+
+
+def test_clone_with_submodules_uses_shallow_submodule_update(
+    tmp_path: Path, mock_run_git_command: Mock
+) -> None:
+    """Submodule init on a fresh clone should use --depth=1."""
+    CORE.config_path = tmp_path / "test.yaml"
+
+    url = "https://github.com/test/repo"
+    domain = "test"
+    repo_dir = _compute_repo_dir(url, None, domain)
+
+    def git_command_side_effect(
+        cmd: list[str], cwd: str | None = None, **kwargs: Any
+    ) -> str:
+        if _get_git_command_type(cmd) == "clone":
+            repo_dir.mkdir(parents=True, exist_ok=True)
+            (repo_dir / ".git").mkdir(exist_ok=True)
+        return ""
+
+    mock_run_git_command.side_effect = git_command_side_effect
+
+    git.clone_or_update(
+        url=url,
+        ref=None,
+        refresh=None,
+        domain=domain,
+        submodules=["components/foo"],
+    )
+
+    submodule_calls = [
+        c for c in mock_run_git_command.call_args_list if "submodule" in c[0][0]
+    ]
+    assert len(submodule_calls) == 1
+    cmd = submodule_calls[0][0][0]
+    assert "--depth=1" in cmd
+    assert "components/foo" in cmd
+    # The `--` terminator must precede the submodule paths so a path
+    # beginning with `-` cannot be parsed as an option.
+    assert cmd.index("--") < cmd.index("components/foo")
+
+
+def test_refresh_fetch_is_shallow(tmp_path: Path, mock_run_git_command: Mock) -> None:
+    """The refresh-path fetch should use --depth=1."""
+    CORE.config_path = tmp_path / "test.yaml"
+
+    url = "https://github.com/test/repo"
+    ref = "main"
+    domain = "test"
+    repo_dir = _compute_repo_dir(url, ref, domain)
+
+    _setup_old_repo(repo_dir)
+    mock_run_git_command.return_value = "abc123"
+
+    git.clone_or_update(
+        url=url, ref=ref, refresh=TimePeriodSeconds(days=1), domain=domain
+    )
+
+    fetch_calls = [c for c in mock_run_git_command.call_args_list if "fetch" in c[0][0]]
+    assert len(fetch_calls) == 1
+    cmd = fetch_calls[0][0][0]
+    assert "--depth=1" in cmd
+    # Ref must still be in the refresh fetch so the right tip is updated.
+    assert cmd[-1] == ref
+
+
+def test_refresh_submodule_update_is_shallow(
+    tmp_path: Path, mock_run_git_command: Mock
+) -> None:
+    """The refresh-path submodule update should use --depth=1."""
+    CORE.config_path = tmp_path / "test.yaml"
+
+    url = "https://github.com/test/repo"
+    domain = "test"
+    repo_dir = _compute_repo_dir(url, None, domain)
+
+    _setup_old_repo(repo_dir)
+    mock_run_git_command.return_value = "abc123"
+
+    git.clone_or_update(
+        url=url,
+        ref=None,
+        refresh=TimePeriodSeconds(days=1),
+        domain=domain,
+        submodules=["components/foo"],
+    )
+
+    submodule_calls = [
+        c for c in mock_run_git_command.call_args_list if "submodule" in c[0][0]
+    ]
+    assert len(submodule_calls) == 1
+    cmd = submodule_calls[0][0][0]
+    assert "--depth=1" in cmd
+    assert "components/foo" in cmd
+    assert cmd.index("--") < cmd.index("components/foo")
+
+
+def test_refresh_picks_up_new_remote_commits(
+    tmp_path: Path, mock_run_git_command: Mock
+) -> None:
+    """Shallow fetch must still pull new commits when the remote tip moves.
+
+    Simulates a stale local repo at SHA "old" while the remote has advanced
+    to SHA "new". The refresh path must run fetch (with --depth=1) followed
+    by reset --hard FETCH_HEAD so the working tree advances to the new tip.
+    """
+    CORE.config_path = tmp_path / "test.yaml"
+
+    url = "https://github.com/test/repo"
+    ref = "main"
+    domain = "test"
+    repo_dir = _compute_repo_dir(url, ref, domain)
+
+    _setup_old_repo(repo_dir)
+
+    # rev-parse is called once before fetch to record the pre-update SHA.
+    rev_parse_calls = {"count": 0}
+
+    def git_command_side_effect(
+        cmd: list[str], cwd: str | None = None, **kwargs: Any
+    ) -> str:
+        cmd_type = _get_git_command_type(cmd)
+        if cmd_type == "rev-parse":
+            rev_parse_calls["count"] += 1
+            return "old_sha"
+        return ""
+
+    mock_run_git_command.side_effect = git_command_side_effect
+
+    _, revert = git.clone_or_update(
+        url=url, ref=ref, refresh=TimePeriodSeconds(days=1), domain=domain
+    )
+
+    # Verify the refresh sequence: rev-parse -> stash -> fetch (depth=1) -> reset
+    call_list = mock_run_git_command.call_args_list
+    cmd_sequence = [_get_git_command_type(c[0][0]) for c in call_list]
+    assert cmd_sequence == ["rev-parse", "stash", "fetch", "reset"]
+
+    fetch_cmd = call_list[2][0][0]
+    assert "--depth=1" in fetch_cmd
+    assert fetch_cmd[-1] == ref
+
+    reset_cmd = call_list[3][0][0]
+    assert reset_cmd[-1] == "FETCH_HEAD"
+
+    # revert callback should reset back to the recorded pre-update SHA.
+    assert revert is not None
+    revert()
+    assert mock_run_git_command.call_args_list[-1][0][0] == [
+        "git",
+        "reset",
+        "--hard",
+        "old_sha",
+    ]
diff --git a/tests/unit_tests/test_helpers.py b/tests/unit_tests/test_helpers.py
index 159d3230ab..f2faf3ba8f 100644
--- a/tests/unit_tests/test_helpers.py
+++ b/tests/unit_tests/test_helpers.py
@@ -90,6 +90,51 @@ def test_cpp_string_escape(string, expected):
     assert actual == expected
 
 
+@pytest.mark.parametrize(
+    "value, expected",
+    (
+        # Basic underscore→dash conversion.
+        ("Living Room Sensor", "living-room-sensor"),
+        # Already-slugified input passes through with dash output.
+        ("kitchen_light", "kitchen-light"),
+        # Accents are stripped (matches the underlying ``slugify``).
+        ("Café Caché", "cafe-cache"),
+        # Mixed casing + multiple separators collapse correctly.
+        ("Foo  Bar__Baz", "foo-bar-baz"),
+        # Empty input yields empty output.
+        ("", ""),
+        # Numbers survive intact.
+        ("Sensor 42", "sensor-42"),
+    ),
+)
+def test_friendly_name_slugify(value, expected):
+    """Friendly-name → URL-safe dash-slug.
+
+    Stable mapping is part of the cross-tool contract
+    (legacy dashboard + device-builder both depend on it for
+    filename → device-name routing). Lock the cases here so a
+    refactor can't accidentally change a slug shape and break
+    on-disk filenames in already-deployed installs.
+    """
+    assert helpers.friendly_name_slugify(value) == expected
+
+
+def test_friendly_name_slugify_back_compat_shim():
+    """``esphome.dashboard.util.text`` keeps re-exporting for back-compat.
+
+    The function moved to ``esphome.helpers`` so the new
+    device-builder dashboard backend can import it without depending
+    on the legacy dashboard package, but downstream code that still
+    imports from the old path keeps working until the dashboard
+    module is removed.
+    """
+    from esphome.dashboard.util.text import (
+        friendly_name_slugify as legacy_friendly_name_slugify,
+    )
+
+    assert legacy_friendly_name_slugify is helpers.friendly_name_slugify
+
+
 @pytest.mark.parametrize(
     "host",
     (
diff --git a/tests/unit_tests/test_loader.py b/tests/unit_tests/test_loader.py
index a42cc5cca7..3fb0eca4a0 100644
--- a/tests/unit_tests/test_loader.py
+++ b/tests/unit_tests/test_loader.py
@@ -158,3 +158,167 @@ def test_component_manifest_resources_with_filter_source_files() -> None:
 
         # Verify the correct number of resources
         assert len(resources) == 3  # test.cpp, test.h, common.cpp
+
+
+# ---------------------------------------------------------------------------
+# recursive_sources — used only by the core "esphome" manifest so that files
+# in esphome/core/<subdir>/*.cpp (e.g. esphome/core/wake/wake_host.cpp) are
+# discovered without promoting <subdir>/ to a Python subpackage.
+# ---------------------------------------------------------------------------
+
+
+def _mock_file(filename: str) -> MagicMock:
+    m = MagicMock()
+    m.name = filename
+    m.is_file.return_value = True
+    m.is_dir.return_value = False
+    return m
+
+
+def _mock_dir(dirname: str, children: list, has_init: bool = False) -> MagicMock:
+    """Mock a directory entry with an iterdir() and joinpath('__init__.py')."""
+    d = MagicMock()
+    d.name = dirname
+    d.is_file.return_value = False
+    d.is_dir.return_value = True
+    d.iterdir.return_value = children
+    init_marker = MagicMock()
+    init_marker.is_file.return_value = has_init
+    d.joinpath.return_value = init_marker
+    return d
+
+
+def test_component_manifest_resources_non_recursive_skips_subdirs() -> None:
+    """Default (recursive_sources=False) does not descend into subdirectories."""
+    mock_module = MagicMock()
+    mock_module.__package__ = "esphome.components.test_component"
+    # No FILTER_SOURCE_FILES.
+    del mock_module.FILTER_SOURCE_FILES
+
+    manifest = ComponentManifest(mock_module)  # recursive_sources defaults to False
+
+    top_level = [
+        _mock_file("top.cpp"),
+        _mock_dir("subdir", [_mock_file("nested.cpp")]),
+    ]
+    with patch("importlib.resources.files") as mock_files_func:
+        pkg = MagicMock()
+        pkg.iterdir.return_value = top_level
+        mock_files_func.return_value = pkg
+
+        names = [r.resource for r in manifest.resources]
+
+    assert names == ["top.cpp"]
+
+
+def test_component_manifest_resources_recursive_walks_non_subpackage_subdirs() -> None:
+    """With recursive_sources=True, a subdir without __init__.py is walked."""
+    mock_module = MagicMock()
+    mock_module.__package__ = "esphome.core"
+    del mock_module.FILTER_SOURCE_FILES
+
+    manifest = ComponentManifest(mock_module, recursive_sources=True)
+
+    wake_dir = _mock_dir(
+        "wake",
+        [
+            _mock_file("wake_host.cpp"),
+            _mock_file("wake_host.h"),
+            _mock_file("README.md"),  # wrong suffix, excluded
+        ],
+        has_init=False,
+    )
+    top_level = [
+        _mock_file("wake.h"),
+        wake_dir,
+    ]
+    with patch("importlib.resources.files") as mock_files_func:
+        pkg = MagicMock()
+        pkg.iterdir.return_value = top_level
+        mock_files_func.return_value = pkg
+
+        names = sorted(r.resource for r in manifest.resources)
+
+    assert names == ["wake.h", "wake/wake_host.cpp", "wake/wake_host.h"]
+
+
+def test_component_manifest_resources_recursive_skips_subpackages() -> None:
+    """Subdirectories that ARE Python subpackages (contain __init__.py) are
+    skipped even with recursive_sources=True — those load as their own
+    ComponentManifest and would otherwise be double-counted."""
+    mock_module = MagicMock()
+    mock_module.__package__ = "esphome.components.haier"
+    del mock_module.FILTER_SOURCE_FILES
+
+    manifest = ComponentManifest(mock_module, recursive_sources=True)
+
+    button_pkg = _mock_dir(
+        "button",
+        [_mock_file("self_cleaning.cpp")],
+        has_init=True,  # Python subpackage — must be skipped.
+    )
+    top_level = [
+        _mock_file("haier.cpp"),
+        button_pkg,
+    ]
+    with patch("importlib.resources.files") as mock_files_func:
+        pkg = MagicMock()
+        pkg.iterdir.return_value = top_level
+        mock_files_func.return_value = pkg
+
+        names = [r.resource for r in manifest.resources]
+
+    assert names == ["haier.cpp"]
+
+
+def test_component_manifest_resources_recursive_skips_pycache() -> None:
+    """__pycache__ inside a recursive walk must never be descended into."""
+    mock_module = MagicMock()
+    mock_module.__package__ = "esphome.core"
+    del mock_module.FILTER_SOURCE_FILES
+
+    manifest = ComponentManifest(mock_module, recursive_sources=True)
+
+    # __pycache__ is_dir=True but must be skipped without checking __init__.py
+    # or calling iterdir (would yield compiled artifacts).
+    pycache = _mock_dir("__pycache__", [_mock_file("wake.cpython-314.pyc")])
+    top_level = [
+        _mock_file("wake.h"),
+        pycache,
+    ]
+    with patch("importlib.resources.files") as mock_files_func:
+        pkg = MagicMock()
+        pkg.iterdir.return_value = top_level
+        mock_files_func.return_value = pkg
+
+        names = [r.resource for r in manifest.resources]
+
+    assert names == ["wake.h"]
+
+
+def test_component_manifest_resources_recursive_filter_source_files_supports_subpaths() -> (
+    None
+):
+    """FILTER_SOURCE_FILES entries using '/'-joined subpaths exclude files
+    inside a recursively-walked subdir."""
+    mock_module = MagicMock()
+    mock_module.__package__ = "esphome.core"
+    mock_module.FILTER_SOURCE_FILES = lambda: ["wake/wake_host.cpp"]
+
+    manifest = ComponentManifest(mock_module, recursive_sources=True)
+
+    wake_dir = _mock_dir(
+        "wake",
+        [
+            _mock_file("wake_host.cpp"),  # excluded
+            _mock_file("wake_freertos.cpp"),  # kept
+        ],
+    )
+    with patch("importlib.resources.files") as mock_files_func:
+        pkg = MagicMock()
+        pkg.iterdir.return_value = [wake_dir]
+        mock_files_func.return_value = pkg
+
+        names = [r.resource for r in manifest.resources]
+
+    assert names == ["wake/wake_freertos.cpp"]
diff --git a/tests/unit_tests/test_main.py b/tests/unit_tests/test_main.py
index 8ec9e70cf8..798a43a4ce 100644
--- a/tests/unit_tests/test_main.py
+++ b/tests/unit_tests/test_main.py
@@ -24,6 +24,7 @@ from esphome.__main__ import (
     _get_configured_xtal_freq,
     _make_crystal_freq_callback,
     _resolve_network_devices,
+    _validate_partition_table_binary,
     choose_upload_log_host,
     command_analyze_memory,
     command_bundle,
@@ -83,6 +84,7 @@ from esphome.const import (
     PLATFORM_RP2040,
 )
 from esphome.core import CORE, EsphomeError
+from esphome.espota2 import OTA_TYPE_UPDATE_APP, OTA_TYPE_UPDATE_PARTITION_TABLE
 from esphome.util import BootselResult
 from esphome.zeroconf import _await_discovery, discover_mdns_devices
 
@@ -1111,6 +1113,7 @@ class MockArgs:
     reset: bool = False
     list_only: bool = False
     output: str | None = None
+    partition_table: bool = False
 
 
 def test_upload_program_serial_esp32(
@@ -1593,7 +1596,7 @@ def test_upload_program_ota_success(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.100"], 3232, "secret", expected_firmware
+        ["192.168.1.100"], 3232, "secret", expected_firmware, OTA_TYPE_UPDATE_APP
     )
 
 
@@ -1624,10 +1627,241 @@ def test_upload_program_ota_with_file_arg(
     assert exit_code == 0
     assert host == "192.168.1.100"
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.100"], 3232, None, Path("custom.bin")
+        ["192.168.1.100"], 3232, None, Path("custom.bin"), OTA_TYPE_UPDATE_APP
     )
 
 
+_PARTITION_TABLE_LEN = 0xC00
+
+
+def _make_partition_table_bytes() -> bytes:
+    """Build a minimal partition table image accepted by _validate_partition_table_binary."""
+    table = bytearray(b"\xff" * _PARTITION_TABLE_LEN)
+    # First entry: ESP_PARTITION_MAGIC (0x50AA) little-endian -> bytes 0xAA, 0x50.
+    table[0] = 0xAA
+    table[1] = 0x50
+    # MD5 checksum entry at offset 32: ESP_PARTITION_MAGIC_MD5 (0xEBEB) little-endian.
+    table[32] = 0xEB
+    table[33] = 0xEB
+    return bytes(table)
+
+
+def test_upload_program_ota_partition_table_with_file_arg(
+    mock_run_ota: Mock,
+    mock_get_port_type: Mock,
+    tmp_path: Path,
+) -> None:
+    """Test upload_program with OTA and partition table."""
+    setup_core(platform=PLATFORM_ESP32, tmp_path=tmp_path)
+
+    mock_get_port_type.return_value = "NETWORK"
+    mock_run_ota.return_value = (0, "192.168.1.100")
+
+    partition_file = tmp_path / "partitions.bin"
+    partition_file.write_bytes(_make_partition_table_bytes())
+
+    config = {
+        CONF_OTA: [
+            {
+                CONF_PLATFORM: CONF_ESPHOME,
+                CONF_PORT: 3232,
+                "allow_partition_access": True,
+            }
+        ]
+    }
+    args = MockArgs(file=str(partition_file), partition_table=True)
+    devices = ["192.168.1.100"]
+
+    exit_code, host = upload_program(config, args, devices)
+
+    assert exit_code == 0
+    assert host == "192.168.1.100"
+    mock_run_ota.assert_called_once_with(
+        ["192.168.1.100"],
+        3232,
+        None,
+        partition_file,
+        OTA_TYPE_UPDATE_PARTITION_TABLE,
+    )
+
+
+def test_upload_program_serial_partition_table(
+    mock_upload_using_esptool: Mock,
+    mock_get_port_type: Mock,
+) -> None:
+    """Test serial upload with partition table option (unsupported)."""
+    setup_core(platform=PLATFORM_ESP32)
+    mock_get_port_type.return_value = "SERIAL"
+    mock_upload_using_esptool.return_value = 0
+
+    config = {}
+    args = MockArgs(partition_table=True)
+    devices = ["/dev/ttyUSB0"]
+
+    with pytest.raises(
+        EsphomeError,
+        match="The option --partition-table can only be used for Over The Air updates",
+    ):
+        upload_program(config, args, devices)
+
+
+def test_upload_program_ota_partition_table_mqttip(
+    mock_run_ota: Mock,
+    mock_get_port_type: Mock,
+    tmp_path: Path,
+) -> None:
+    """--partition-table is allowed for MQTTIP devices; they resolve to a real IP at OTA time."""
+    setup_core(platform=PLATFORM_ESP32, tmp_path=tmp_path)
+
+    mock_get_port_type.return_value = "MQTTIP"
+    mock_run_ota.return_value = (0, "192.168.1.100")
+
+    partition_file = tmp_path / "partitions.bin"
+    partition_file.write_bytes(_make_partition_table_bytes())
+
+    config = {
+        CONF_OTA: [
+            {
+                CONF_PLATFORM: CONF_ESPHOME,
+                CONF_PORT: 3232,
+                "allow_partition_access": True,
+            }
+        ]
+    }
+    args = MockArgs(file=str(partition_file), partition_table=True)
+
+    with patch(
+        "esphome.__main__._resolve_network_devices", return_value=["192.168.1.100"]
+    ):
+        exit_code, host = upload_program(config, args, ["MQTTIP"])
+
+    assert exit_code == 0
+    assert host == "192.168.1.100"
+    mock_run_ota.assert_called_once_with(
+        ["192.168.1.100"],
+        3232,
+        None,
+        partition_file,
+        OTA_TYPE_UPDATE_PARTITION_TABLE,
+    )
+
+
+def test_validate_partition_table_binary_accepts_valid(tmp_path: Path) -> None:
+    f = tmp_path / "partitions.bin"
+    f.write_bytes(_make_partition_table_bytes())
+    _validate_partition_table_binary(f)
+
+
+_PARTITION_FIXTURE_DIR = Path(__file__).parent / "fixtures" / "partition_tables"
+
+
+@pytest.mark.parametrize(
+    "fixture",
+    [
+        # Stock ESP-IDF gen_esp32part.py output for an ESPHome build.
+        "esphome_default.bin",
+        # ESP-IDF Hello-world example partition table (vendored from espressif/esp-serial-flasher).
+        "esp_idf_hello_world.bin",
+        # Partition table shipped with esphome_dashboard's prebuilt firmware.
+        "esphome_dashboard_firmware.bin",
+    ],
+)
+def test_validate_partition_table_binary_accepts_real_binaries(fixture: str) -> None:
+    """Real-world partition-table binaries from ESP-IDF / ESPHome tooling pass validation."""
+    _validate_partition_table_binary(_PARTITION_FIXTURE_DIR / fixture)
+
+
+def test_validate_partition_table_binary_rejects_wrong_size(tmp_path: Path) -> None:
+    f = tmp_path / "partitions.bin"
+    f.write_bytes(b"\xaa\x50" + b"\xff" * 100)
+    with pytest.raises(EsphomeError, match="wrong size"):
+        _validate_partition_table_binary(f)
+
+
+def test_validate_partition_table_binary_rejects_wrong_magic(tmp_path: Path) -> None:
+    data = bytearray(_make_partition_table_bytes())
+    data[0] = 0x00
+    data[1] = 0x00
+    f = tmp_path / "partitions.bin"
+    f.write_bytes(bytes(data))
+    with pytest.raises(EsphomeError, match="partition magic"):
+        _validate_partition_table_binary(f)
+
+
+def test_validate_partition_table_binary_rejects_missing_md5(tmp_path: Path) -> None:
+    data = bytearray(_make_partition_table_bytes())
+    data[32] = 0xFF
+    data[33] = 0xFF
+    f = tmp_path / "partitions.bin"
+    f.write_bytes(bytes(data))
+    with pytest.raises(EsphomeError, match="missing the MD5 checksum entry"):
+        _validate_partition_table_binary(f)
+
+
+def test_validate_partition_table_binary_missing_file(tmp_path: Path) -> None:
+    with pytest.raises(EsphomeError, match="Cannot read partition table file"):
+        _validate_partition_table_binary(tmp_path / "does-not-exist.bin")
+
+
+def test_upload_program_ota_partition_table_invalid_file(
+    mock_run_ota: Mock,
+    mock_get_port_type: Mock,
+    tmp_path: Path,
+) -> None:
+    """--partition-table must fail before calling run_ota when the file is not a partition table."""
+    setup_core(platform=PLATFORM_ESP32, tmp_path=tmp_path)
+
+    mock_get_port_type.return_value = "NETWORK"
+
+    bad_file = tmp_path / "firmware.bin"
+    bad_file.write_bytes(b"\x00" * 4096)
+
+    config = {
+        CONF_OTA: [
+            {
+                CONF_PLATFORM: CONF_ESPHOME,
+                CONF_PORT: 3232,
+                "allow_partition_access": True,
+            }
+        ]
+    }
+    args = MockArgs(file=str(bad_file), partition_table=True)
+    devices = ["192.168.1.100"]
+
+    with pytest.raises(EsphomeError, match="wrong size"):
+        upload_program(config, args, devices)
+    mock_run_ota.assert_not_called()
+
+
+def test_upload_program_ota_partition_table_without_allow_flag(
+    mock_run_ota: Mock,
+    mock_get_port_type: Mock,
+    tmp_path: Path,
+) -> None:
+    """--partition-table must fail fast when allow_partition_access is not enabled in YAML."""
+    setup_core(platform=PLATFORM_ESP32, tmp_path=tmp_path)
+
+    mock_get_port_type.return_value = "NETWORK"
+
+    config = {
+        CONF_OTA: [
+            {
+                CONF_PLATFORM: CONF_ESPHOME,
+                CONF_PORT: 3232,
+            }
+        ]
+    }
+    args = MockArgs(file="partitions.bin", partition_table=True)
+    devices = ["192.168.1.100"]
+
+    with pytest.raises(
+        EsphomeError,
+        match="requires 'allow_partition_access: true'",
+    ):
+        upload_program(config, args, devices)
+    mock_run_ota.assert_not_called()
+
+
 def test_upload_program_ota_no_config(
     mock_get_port_type: Mock,
 ) -> None:
@@ -1682,7 +1916,7 @@ def test_upload_program_ota_with_mqtt_resolution(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.100"], 3232, None, expected_firmware
+        ["192.168.1.100"], 3232, None, expected_firmware, OTA_TYPE_UPDATE_APP
     )
 
 
@@ -1730,7 +1964,7 @@ def test_upload_program_ota_with_mqtt_empty_broker(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.50"], 3232, None, expected_firmware
+        ["192.168.1.50"], 3232, None, expected_firmware, OTA_TYPE_UPDATE_APP
     )
     # Verify warning was logged
     assert "MQTT IP discovery failed" in caplog.text
@@ -2605,7 +2839,7 @@ def test_choose_upload_log_host_discovers_mac_suffix_devices(tmp_path: Path) ->
     }
     with (
         patch(
-            "esphome.__main__.discover_mdns_devices", return_value=discovered
+            "esphome.zeroconf.discover_mdns_devices", return_value=discovered
         ) as mock_discover,
         patch(
             "esphome.__main__.choose_prompt", return_value="mydevice-abc123.local"
@@ -2653,7 +2887,7 @@ def test_choose_upload_log_host_mac_suffix_no_devices_found(
     )
 
     with (
-        patch("esphome.__main__.discover_mdns_devices", return_value={}),
+        patch("esphome.zeroconf.discover_mdns_devices", return_value={}),
         caplog.at_level(logging.WARNING, logger="esphome.__main__"),
         pytest.raises(EsphomeError),
     ):
@@ -2686,7 +2920,7 @@ def test_choose_upload_log_host_default_ota_discovers_mac_suffix(
         "mydevice-def456.local": ["10.0.0.2"],
     }
     with patch(
-        "esphome.__main__.discover_mdns_devices", return_value=discovered
+        "esphome.zeroconf.discover_mdns_devices", return_value=discovered
     ) as mock_discover:
         result = choose_upload_log_host(
             default="OTA",
@@ -2715,7 +2949,7 @@ def test_choose_upload_log_host_default_ota_no_suffix_discovery(
         name="mydevice",
     )
 
-    with patch("esphome.__main__.discover_mdns_devices") as mock_discover:
+    with patch("esphome.zeroconf.discover_mdns_devices") as mock_discover:
         result = choose_upload_log_host(
             default="OTA",
             check_default=None,
@@ -3207,7 +3441,11 @@ def test_upload_program_ota_static_ip_with_mqttip(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.100", "192.168.2.50"], 3232, None, expected_firmware
+        ["192.168.1.100", "192.168.2.50"],
+        3232,
+        None,
+        expected_firmware,
+        OTA_TYPE_UPDATE_APP,
     )
 
 
@@ -3250,7 +3488,11 @@ def test_upload_program_ota_multiple_mqttip_resolves_once(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.2.50", "192.168.2.51", "192.168.1.100"], 3232, None, expected_firmware
+        ["192.168.2.50", "192.168.2.51", "192.168.1.100"],
+        3232,
+        None,
+        expected_firmware,
+        OTA_TYPE_UPDATE_APP,
     )
 
 
@@ -3415,7 +3657,7 @@ def test_upload_program_ota_mqtt_timeout_fallback(
         tmp_path / ".esphome" / "build" / "test" / ".pioenvs" / "test" / "firmware.bin"
     )
     mock_run_ota.assert_called_once_with(
-        ["192.168.1.100"], 3232, None, expected_firmware
+        ["192.168.1.100"], 3232, None, expected_firmware, OTA_TYPE_UPDATE_APP
     )
 
 
diff --git a/tests/unit_tests/test_platformio_api.py b/tests/unit_tests/test_platformio_api.py
index 67e64e5f61..b241622f89 100644
--- a/tests/unit_tests/test_platformio_api.py
+++ b/tests/unit_tests/test_platformio_api.py
@@ -311,6 +311,105 @@ def test_run_platformio_cli_sets_environment_variables(
         assert "arg" in args
 
 
+@pytest.mark.parametrize(
+    ("platform", "input_path", "expected"),
+    [
+        # win32: drive-letter extended-length prefix is stripped
+        (
+            "win32",
+            "\\\\?\\C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe",
+            "C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe",
+        ),
+        # win32: UNC extended-length prefix is translated to a regular UNC path
+        (
+            "win32",
+            "\\\\?\\UNC\\server\\share\\python.exe",
+            "\\\\server\\share\\python.exe",
+        ),
+        # win32: paths without the prefix are returned unchanged
+        (
+            "win32",
+            "C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe",
+            "C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe",
+        ),
+        # non-win32: prefix is left alone (no-op)
+        ("linux", "\\\\?\\C:\\python.exe", "\\\\?\\C:\\python.exe"),
+        ("darwin", "/usr/bin/python3", "/usr/bin/python3"),
+    ],
+)
+def test_strip_win_long_path_prefix(
+    platform: str, input_path: str, expected: str
+) -> None:
+    r"""``\\?\`` and ``\\?\UNC\`` prefixes are stripped only on win32."""
+    with patch("esphome.platformio_api.sys.platform", platform):
+        assert platformio_api._strip_win_long_path_prefix(input_path) == expected
+
+
+def test_run_platformio_cli_strips_win_long_path_prefix(
+    setup_core: Path, mock_run_external_process: Mock
+) -> None:
+    r"""Windows ``\\?\`` prefix on sys.executable does not leak into the subprocess.
+
+    The NSIS-installed esphome.exe launcher starts Python with
+    ``sys.executable`` already prefixed by the extended-length path marker.
+    That prefix would otherwise propagate into PlatformIO's ``PYTHONEXE`` and
+    break SCons-emitted command lines run through ``cmd.exe``.
+    """
+    CORE.build_path = str(setup_core / "build" / "test")
+    prefixed_exe = (
+        "\\\\?\\C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe"
+    )
+    stripped_exe = (
+        "C:\\Users\\jesse\\AppData\\Local\\ESPHome Builder\\python\\python.exe"
+    )
+
+    with (
+        patch.dict(os.environ, {}, clear=False),
+        patch("esphome.platformio_api.sys.platform", "win32"),
+        patch("esphome.platformio_api.sys.executable", prefixed_exe),
+    ):
+        # Pop any pre-existing PYTHONEXEPATH so the assertion below reflects
+        # what run_platformio_cli set, not whatever the test runner's
+        # environment happened to contain.
+        os.environ.pop("PYTHONEXEPATH", None)
+        mock_run_external_process.return_value = 0
+        platformio_api.run_platformio_cli("test", "arg")
+
+        # The subprocess is invoked with the stripped executable path.
+        mock_run_external_process.assert_called_once()
+        args = mock_run_external_process.call_args[0]
+        assert args[0] == stripped_exe
+        # PYTHONEXEPATH is exported with the stripped path so PlatformIO's
+        # get_pythonexe_path() picks it up in the subprocess.
+        assert os.environ["PYTHONEXEPATH"] == stripped_exe
+
+
+def test_run_platformio_cli_does_not_set_pythonexepath_without_strip(
+    setup_core: Path, mock_run_external_process: Mock
+) -> None:
+    r"""PYTHONEXEPATH is not touched when sys.executable has no ``\\?\`` prefix.
+
+    Setting it unconditionally would clobber a user-provided value (or
+    interfere with non-Windows tooling that has no prefix to strip).
+    """
+    CORE.build_path = str(setup_core / "build" / "test")
+    plain_exe = "/usr/bin/python3"
+
+    with (
+        patch.dict(os.environ, {}, clear=False),
+        patch("esphome.platformio_api.sys.platform", "linux"),
+        patch("esphome.platformio_api.sys.executable", plain_exe),
+    ):
+        os.environ.pop("PYTHONEXEPATH", None)
+        mock_run_external_process.return_value = 0
+        platformio_api.run_platformio_cli("test", "arg")
+
+        mock_run_external_process.assert_called_once()
+        args = mock_run_external_process.call_args[0]
+        assert args[0] == plain_exe
+        assert "PYTHONEXEPATH" not in os.environ
+
+
 def test_run_platformio_cli_run_builds_command(
     setup_core: Path, mock_run_platformio_cli: Mock
 ) -> None:
diff --git a/tests/unit_tests/test_zeroconf.py b/tests/unit_tests/test_zeroconf.py
new file mode 100644
index 0000000000..e325eb1e26
--- /dev/null
+++ b/tests/unit_tests/test_zeroconf.py
@@ -0,0 +1,237 @@
+"""Unit tests for ``esphome.zeroconf`` device-discovery primitives.
+
+Covers ``DashboardImportDiscovery`` (state transitions for adoption /
+import flows) and ``DiscoveredImport`` (TXT-record parse shape). Both
+are part of the cross-tool contract between the legacy dashboard and
+the new device-builder backend (esphome/device-builder); changes to
+the callback signature, the ``import_state`` dict shape, or the
+``DiscoveredImport`` field set will break downstream consumers.
+"""
+
+from __future__ import annotations
+
+from unittest.mock import MagicMock
+
+from zeroconf import ServiceStateChange
+
+from esphome.zeroconf import (
+    ESPHOME_SERVICE_TYPE,
+    DashboardImportDiscovery,
+    DiscoveredImport,
+)
+
+
+def _make_service_info(
+    package_import_url: str = "github://esphome/example/example.yaml",
+    project_name: str = "esphome.example",
+    project_version: str = "1.0.0",
+    network: str | None = "wifi",
+    friendly_name: str | None = "Living Room",
+    version: str | None = "2025.1.0",
+) -> MagicMock:
+    """Build a fake ``AsyncServiceInfo`` with the TXT records we care about.
+
+    The real callback path resolves a service via zeroconf and then
+    reads ``info.properties`` (a ``dict[bytes, bytes | None]``). Mock
+    that shape so we can drive ``_process_service_info`` directly
+    without spinning up a real zeroconf instance.
+    """
+    info = MagicMock()
+    properties: dict[bytes, bytes | None] = {
+        b"package_import_url": package_import_url.encode(),
+        b"project_name": project_name.encode(),
+        b"project_version": project_version.encode(),
+    }
+    if network is not None:
+        properties[b"network"] = network.encode()
+    if friendly_name is not None:
+        properties[b"friendly_name"] = friendly_name.encode()
+    if version is not None:
+        properties[b"version"] = version.encode()
+    info.properties = properties
+    info.load_from_cache.return_value = True
+    return info
+
+
+def test_added_service_populates_import_state_and_fires_callback() -> None:
+    """An ADD with the required TXT records lands a ``DiscoveredImport`` and notifies.
+
+    Mirrors what both the legacy dashboard and device-builder rely
+    on — the callback is the only signal that an importable device
+    has appeared on the LAN, and ``import_state`` is the snapshot
+    they read on demand.
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    info = _make_service_info()
+    name = f"living-room.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+
+    assert name in discovery.import_state
+    entry = discovery.import_state[name]
+    assert isinstance(entry, DiscoveredImport)
+    assert entry.device_name == "living-room"
+    assert entry.package_import_url == "github://esphome/example/example.yaml"
+    assert entry.project_name == "esphome.example"
+    assert entry.project_version == "1.0.0"
+    assert entry.network == "wifi"
+    assert entry.friendly_name == "Living Room"
+    on_update.assert_called_once_with(name, entry)
+
+
+def test_added_service_without_required_txt_is_ignored() -> None:
+    """A device that doesn't carry ``package_import_url`` etc. isn't importable.
+
+    The dashboard browser also fires for plain ``_esphomelib._tcp``
+    services that happen to match the type but aren't dashboard
+    imports. Those must not land in ``import_state`` or fire the
+    update callback — otherwise the dashboard would surface every
+    API-enabled device on the LAN as "ready to adopt".
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    info = MagicMock()
+    # Empty TXT records — no import URL, no version. ``version``-only
+    # services hit a separate ``update_device_mdns`` path that talks
+    # to ``StorageJSON``; that's covered elsewhere.
+    info.properties = {}
+    info.load_from_cache.return_value = True
+
+    discovery._process_service_info(f"plain.{ESPHOME_SERVICE_TYPE}", info)
+
+    assert discovery.import_state == {}
+    on_update.assert_not_called()
+
+
+def test_repeated_add_does_not_re_fire_callback() -> None:
+    """Re-resolving the same service doesn't spam the on_update callback.
+
+    The dashboard re-resolves periodically; without the ``is_new``
+    guard, every refresh would fire ``IMPORTABLE_DEVICE_ADDED`` and
+    the dashboard's UI would re-render endlessly.
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    info = _make_service_info()
+    name = f"living-room.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+    discovery._process_service_info(name, info)
+
+    on_update.assert_called_once()
+
+
+def test_removed_service_clears_state_and_fires_none_callback() -> None:
+    """A ServiceStateChange.Removed pops the entry and notifies with ``None``.
+
+    Both consumers rely on the ``(name, None)`` callback shape to
+    distinguish "device gone" from "device updated". Coordinate
+    before changing the second-arg semantics.
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    info = _make_service_info()
+    name = f"living-room.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+    on_update.reset_mock()
+
+    discovery.browser_callback(
+        zeroconf=MagicMock(),
+        service_type=ESPHOME_SERVICE_TYPE,
+        name=name,
+        state_change=ServiceStateChange.Removed,
+    )
+
+    assert name not in discovery.import_state
+    on_update.assert_called_once_with(name, None)
+
+
+def test_remove_for_unknown_service_does_not_fire_callback() -> None:
+    """A spurious Removed for a service we never tracked is a silent no-op.
+
+    The browser can fire Removed for any matching service type,
+    not just the importable ones we're tracking. Don't let those
+    confuse the callback consumer.
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    discovery.browser_callback(
+        zeroconf=MagicMock(),
+        service_type=ESPHOME_SERVICE_TYPE,
+        name=f"never-seen.{ESPHOME_SERVICE_TYPE}",
+        state_change=ServiceStateChange.Removed,
+    )
+
+    on_update.assert_not_called()
+
+
+def test_updated_service_for_unknown_name_is_ignored() -> None:
+    """Updates without a prior Add don't seed ``import_state``.
+
+    The dashboard counts on Add to introduce the device and Update
+    to refresh it. Letting Update silently introduce new state would
+    let an unrelated TXT change bypass the Add-time validation.
+    """
+    on_update = MagicMock()
+    discovery = DashboardImportDiscovery(on_update=on_update)
+
+    discovery.browser_callback(
+        zeroconf=MagicMock(),
+        service_type=ESPHOME_SERVICE_TYPE,
+        name=f"living-room.{ESPHOME_SERVICE_TYPE}",
+        state_change=ServiceStateChange.Updated,
+    )
+
+    assert discovery.import_state == {}
+    on_update.assert_not_called()
+
+
+def test_network_defaults_to_wifi_when_txt_absent() -> None:
+    """Older firmware that doesn't broadcast ``network`` defaults to ``wifi``.
+
+    The TXT record was added in a later release; pre-existing
+    factory firmwares advertise without it. ``DiscoveredImport``
+    has to default cleanly so adoption flows can still produce a
+    valid YAML for those devices.
+    """
+    discovery = DashboardImportDiscovery()
+    info = _make_service_info(network=None)
+    name = f"older.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+
+    assert discovery.import_state[name].network == "wifi"
+
+
+def test_friendly_name_optional() -> None:
+    """``friendly_name`` may be ``None`` if the device doesn't broadcast it.
+
+    Both consumers handle the ``None`` case (rendering the device
+    name as fallback in the UI). Locking this in keeps the
+    optionality explicit so a future refactor doesn't accidentally
+    coerce it into an empty string.
+    """
+    discovery = DashboardImportDiscovery()
+    info = _make_service_info(friendly_name=None)
+    name = f"no-friendly.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+
+    assert discovery.import_state[name].friendly_name is None
+
+
+def test_callback_is_optional() -> None:
+    """``on_update=None`` lets ``import_state`` track silently.
+
+    Used by callers that read the dict directly rather than
+    subscribing to events.
+    """
+    discovery = DashboardImportDiscovery(on_update=None)
+    info = _make_service_info()
+    name = f"silent.{ESPHOME_SERVICE_TYPE}"
+    discovery._process_service_info(name, info)
+
+    # No callback to assert against; just verify state landed.
+    assert name in discovery.import_state