[libretiny] Shorten the LN882x zero-size allocation comment

[libretiny] Trim the LN882x zero-size allocation comments
[libretiny] Keep zero-size allocations from hanging the LN882x
2026-10-14 18:22:48 +00:00 · 2026-10-04 21:55:28 -05:00 · 2026-10-04 18:50:42 -05:00 · 2026-10-04 18:01:26 -05:00 · 2026-10-05 09:26:21 +13:00 · 2026-10-05 09:25:35 +13:00
877 changed files with 35575 additions and 8741 deletions
@@ -0,0 +1,39 @@
+name: Cache Arduino ESP8266
+description: >
+  Resolve the pinned Arduino core and xtensa toolchain versions and cache the
+  native ESP8266 install (~110 MB framework + toolchain; no ccache store, the
+  seed job saves before any compile runs). Exports
+  ESPHOME_ARDUINO8266_PREFIX to the job so every later step installs into
+  the cached path; the Python venv must already be restored. Mirrors
+  cache-esp-idf: only dev-branch pushes write the shared cache, everything
+  else restores.
+runs:
+  using: composite
+  steps:
+    - name: Resolve the native toolchain cache key
+      # Versions are pinned in code, not a hashable file; resolve them so a
+      # bump changes the cache key. Assignment form so errexit catches a
+      # resolver failure.
+      id: version
+      shell: bash
+      run: |
+        # One owner for the install prefix: exported here and referenced by
+        # the cache steps below via env, so the caller's install and the
+        # cached path cannot diverge.
+        echo "ESPHOME_ARDUINO8266_PREFIX=$HOME/.esphome-arduino8266" >> "$GITHUB_ENV"
+        . venv/bin/activate
+        key=$(python -c 'from esphome.components.esp8266 import RECOMMENDED_ARDUINO_FRAMEWORK_VERSION as f; from esphome.arduino8266.framework import FRAMEWORK_RELEASES, TOOLCHAIN_VERSION as t; print(f"{FRAMEWORK_RELEASES[f].tag}-{t}")')
+        [ -n "$key" ] || exit 1
+        echo "key=$key" >> "$GITHUB_OUTPUT"
+    - name: Cache the native toolchain (write on dev)
+      if: github.ref == 'refs/heads/dev'
+      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      with:
+        path: ${{ env.ESPHOME_ARDUINO8266_PREFIX }}
+        key: ${{ runner.os }}-esp8266-native-${{ steps.version.outputs.key }}
+    - name: Restore the native toolchain (off dev)
+      if: github.ref != 'refs/heads/dev'
+      uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      with:
+        path: ${{ env.ESPHOME_ARDUINO8266_PREFIX }}
+        key: ${{ runner.os }}-esp8266-native-${{ steps.version.outputs.key }}
@@ -19,6 +19,7 @@ on:
      - "esphome/core/**"
      - "esphome/writer.py"
      - "esphome/build_gen/**"
+      - "esphome/build_helpers/**"
      - "esphome/espidf/**"
      - "esphome/platformio/**"
      - "esphome/components/bk72xx/**"
@@ -195,6 +196,7 @@ jobs:
        # the default.
        id:
          - esp8266-arduino
+          - esp8266-arduino-native
          - esp32-arduino-platformio
          - esp32-arduino-esp-idf
          - esp32-idf-platformio
@@ -217,5 +219,6 @@ jobs:
        run: |
          docker run --rm \
            -v "${{ github.workspace }}/docker/test_configs:/config" \
+            -e ESPHOME_LDGEN_STRICT=1 \
            "ghcr.io/esphome/esphome-amd64:${{ needs.check-docker.outputs.tag }}" \
            compile "${{ matrix.id }}.yaml"
@@ -102,6 +102,8 @@ jobs:
      device-builder: ${{ steps.determine.outputs.device-builder }}
      esp32-platformio: ${{ steps.determine.outputs.esp32-platformio }}
      esp32-platformio-components: ${{ steps.determine.outputs.esp32-platformio-components }}
+      esp8266-native: ${{ steps.determine.outputs.esp8266-native }}
+      esp8266-native-components: ${{ steps.determine.outputs.esp8266-native-components }}
      changed-components: ${{ steps.determine.outputs.changed-components }}
      changed-components-with-tests: ${{ steps.determine.outputs.changed-components-with-tests }}
      directly-changed-components-with-tests: ${{ steps.determine.outputs.directly-changed-components-with-tests }}
@@ -165,6 +167,8 @@ jobs:
          echo "device-builder=$(echo "$output" | jq -r '.device_builder')" >> $GITHUB_OUTPUT
          echo "esp32-platformio=$(echo "$output" | jq -r '.esp32_platformio')" >> $GITHUB_OUTPUT
          echo "esp32-platformio-components=$(echo "$output" | jq -r '.esp32_platformio_components')" >> $GITHUB_OUTPUT
+          echo "esp8266-native=$(echo "$output" | jq -r '.esp8266_native')" >> $GITHUB_OUTPUT
+          echo "esp8266-native-components=$(echo "$output" | jq -r '.esp8266_native_components')" >> $GITHUB_OUTPUT
          echo "changed-components=$(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')" >> $GITHUB_OUTPUT
@@ -183,6 +187,33 @@ jobs:
          path: .temp/components_graph.json
          key: components-graph-${{ hashFiles('esphome/components/**/*.py') }}

+  seed-esp8266-native-cache:
+    name: Seed the esp8266 native toolchain cache
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+    # PR-branch cache saves are invisible to other PRs, so dev pushes seed
+    # the shared entry the component matrix, the memory impact jobs and
+    # test-esp8266-native restore. Only dev: the composite action saves
+    # nowhere else, so a beta/release push would download the toolchain and
+    # discard it.
+    if: github.event_name == 'push' && github.ref == 'refs/heads/dev'
+    timeout-minutes: 15
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Cache the native toolchain
+        uses: ./.github/actions/cache-arduino8266
+      - name: Install the native toolchain
+        run: |
+          . venv/bin/activate
+          python -c "from esphome.arduino8266.framework import check_and_install; from esphome.components.esp8266 import RECOMMENDED_ARDUINO_FRAMEWORK_VERSION; check_and_install(RECOMMENDED_ARDUINO_FRAMEWORK_VERSION)"
+
  ci-custom:
    name: Run script/ci-custom
    runs-on: ubuntu-24.04
@@ -268,7 +299,7 @@ jobs:
      # Pushes any fixes the hooks made back to the pull request. This step
      # must keep its default name: the GitHub App that performs the push
      # locates the workflow run by that name.
-      - uses: pre-commit-ci/lite-action@5d6cc0eb514c891a40562a58a8e71576c5c7fb43 # v1.1.0
+      - uses: pre-commit-ci/lite-action@062bca0919bc9d6e66755cc05074b70c77e111fc # v1.2.0
        if: always()
        with:
          msg: apply automatic formatting fixes
@@ -369,14 +400,9 @@ jobs:
      matrix:
        bucket: ${{ fromJson(needs.determine-jobs.outputs.integration-test-buckets) }}
    env:
-      # What the cache steps persist; libdeps is excluded (keyed per xdist
-      # worker and env, it never crosses runs).
-      INTEGRATION_PIO_CACHE_PATH: |
-        ~/.esphome-integration-tests/platformio/platforms
-        ~/.esphome-integration-tests/platformio/packages
-        ~/.esphome-integration-tests/platformio/appstate.json
-        ~/.esphome-integration-tests/platformio/.cache
-        ~/.esphome-integration-tests/platformio/.esphome.pio.stamp.json
+      # Registry libraries (noise-c, libsodium, ArduinoJson, lvgl) the host builds
+      # download, shared per xdist worker by tests/integration/conftest.py
+      INTEGRATION_LIBRARY_CACHE_PATH: ~/.esphome-integration-tests/pio_components
    steps:
      - name: Check out code from GitHub
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
@@ -396,14 +422,13 @@ jobs:
        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
        with:
          python-version: "3.13"
-      - name: Restore integration PlatformIO cache
-        # Native platform + toolchain installed by shared_platformio_cache in
-        # tests/integration/conftest.py; a miss self-heals, so no restore-keys.
-        id: pio-cache
+      - name: Restore integration library cache
+        # A miss or a changed pin self-heals with a download, so no restore-keys
+        id: library-cache
        uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
        with:
-          path: ${{ env.INTEGRATION_PIO_CACHE_PATH }}
-          key: integration-pio-v1-${{ runner.os }}-py${{ steps.python.outputs.python-version }}-${{ hashFiles('requirements.txt', 'tests/integration/fixtures/cache_init.yaml', 'esphome/components/host/__init__.py') }}
+          path: ${{ env.INTEGRATION_LIBRARY_CACHE_PATH }}
+          key: integration-libraries-v1-${{ runner.os }}-${{ hashFiles('esphome/components/json/__init__.py', 'esphome/components/noise/__init__.py', 'esphome/components/lvgl/__init__.py', 'esphome/components/improv_base/__init__.py') }}
      - name: Restore Python virtual environment
        id: cache-venv
        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
@@ -471,16 +496,16 @@ jobs:
          # A full cron period of margin for the weekly refresh
          retention-days: 14
      - name: Print ccache statistics
-        # esphome stores the PlatformIO ccache under the machine-global cache
-        # dir (see _ccache_env() in esphome/platformio/toolchain.py).
-        run: CCACHE_DIR="$HOME/.cache/esphome/platformio-ccache" ccache -s
-      - name: Save integration PlatformIO cache
+        # esphome stores the host build's ccache under the machine-global
+        # cache dir (see get_build_env() in esphome/host/toolchain.py).
+        run: CCACHE_DIR="$HOME/.cache/esphome/host/ccache" ccache -s
+      - name: Save integration library cache
        # Bucket 0 only; the others would race the same immutable key.
-        if: success() && (github.ref == 'refs/heads/dev' || contains(github.event.pull_request.labels.*.name, 'ci-cache-write')) && strategy.job-index == 0 && steps.pio-cache.outputs.cache-hit != 'true'
+        if: success() && (github.ref == 'refs/heads/dev' || contains(github.event.pull_request.labels.*.name, 'ci-cache-write')) && strategy.job-index == 0 && steps.library-cache.outputs.cache-hit != 'true'
        uses: actions/cache/save@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
        with:
-          path: ${{ env.INTEGRATION_PIO_CACHE_PATH }}
-          key: ${{ steps.pio-cache.outputs.cache-primary-key }}
+          path: ${{ env.INTEGRATION_LIBRARY_CACHE_PATH }}
+          key: ${{ steps.library-cache.outputs.cache-primary-key }}

  import-time:
    name: Check import esphome.__main__ time
@@ -1097,6 +1122,11 @@ jobs:
        uses: ./.github/actions/cache-sdk-nrf
        with:
          restore-only: true
+      - name: Cache the native ESP8266 toolchain
+        # Only batches whose test platforms include esp8266; never saves
+        # here, it reuses the install the dev seed job cached.
+        if: matrix.batch.needs_arduino8266
+        uses: ./.github/actions/cache-arduino8266
      - name: Validate and compile components with intelligent grouping
        run: |
          . venv/bin/activate
@@ -1195,9 +1225,28 @@ jobs:

          if [ -n "$compile_csv" ]; then
            # Run compilation with grouping and isolation
-            python3 script/test_build_components.py -e compile -c "$compile_csv" -f --isolate "$directly_changed_csv"
+            # The bootloader has no ESPHome code and these builds never
+            # flash; the check_idf_py batch keeps the full build so the
+            # native sub-build and the equivalence check stay covered.
+            skip_flag="--skip-bootloader"
+            if [[ "${{ matrix.batch.check_idf_py }}" == "true" ]]; then
+              skip_flag=""
+            fi
+            python3 script/test_build_components.py -e compile -c "$compile_csv" -f --isolate "$directly_changed_csv" $skip_flag
+            if [[ "${{ matrix.batch.check_idf_py }}" == "true" ]]; then
+              # The real idf.py must find nothing to configure or build in a
+              # tree built above; catches drift on ESP-IDF bumps.
+              echo "Checking the native ESP-IDF build matches idf.py"
+              python3 script/check_idf_py_equivalence.py
+            fi
          else
            echo "All components in this batch are validate-only -- skipping compile stage."
+            if [[ "${{ matrix.batch.check_idf_py }}" == "true" ]]; then
+              # determine-jobs and this step disagree on what compiles; fail
+              # rather than let the check run nowhere.
+              echo "::error::This batch was picked for the idf.py check but compiled nothing"
+              exit 1
+            fi
          fi

      - name: Print ccache statistics
@@ -1237,7 +1286,7 @@ jobs:

          # compile validates config first, so a separate config pass is
          # redundant for this smoke test. ESP-IDF framework via PlatformIO:
-          python3 script/test_build_components.py -e compile -t esp32-idf -c "$TEST_COMPONENTS" -f --toolchain platformio
+          python3 script/test_build_components.py -e compile -t esp32-idf -c "$TEST_COMPONENTS" -f --toolchain platformio --fail-on-no-tests

          echo ""
          echo "ESP-IDF-via-PlatformIO build passed! Starting Arduino smoke test..."
@@ -1246,6 +1295,40 @@ jobs:
          # Arduino framework via PlatformIO (only components with an esp32-ard test are built):
          python3 script/test_build_components.py -e compile -t esp32-ard -c "$TEST_COMPONENTS" -f --toolchain platformio

+  test-esp8266-native:
+    name: Test esp8266 components with the native toolchain
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: github.event_name == 'pull_request' && needs.determine-jobs.outputs.esp8266-native == 'true'
+    env:
+      # Computed by script/determine-jobs.py (ESP8266_NATIVE_TEST_COMPONENTS)
+      TEST_COMPONENTS: ${{ needs.determine-jobs.outputs.esp8266-native-components }}
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+
+      - name: Cache the native toolchain
+        uses: ./.github/actions/cache-arduino8266
+
+      - name: Run native toolchain compile test
+        run: |
+          . venv/bin/activate
+
+          echo "Testing components: $TEST_COMPONENTS"
+          echo ""
+
+          # ESP8266 Arduino built directly (no PlatformIO); compile validates
+          # config first, so a separate config pass is redundant.
+          python3 script/test_build_components.py -e compile -t esp8266-ard -c "$TEST_COMPONENTS" -f --toolchain arduino --fail-on-no-tests
+
  device-builder:
    name: Test downstream esphome/device-builder
    runs-on: ubuntu-24.04
@@ -1415,12 +1498,9 @@ jobs:
          python-version: ${{ env.DEFAULT_PYTHON }}
          cache-key: ${{ needs.common.outputs.cache-key }}

-      - name: Cache platformio
-        if: steps.check-script.outputs.skip != 'true' && steps.check-tests.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true'
-        uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
-        with:
-          path: ~/.platformio
-          key: platformio-memory-${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}-${{ hashFiles('platformio.ini') }}
+      - name: Cache the native ESP8266 toolchain
+        if: steps.check-script.outputs.skip != 'true' && steps.check-tests.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true' && fromJSON(needs.determine-jobs.outputs.memory_impact).needs_arduino8266
+        uses: ./.github/actions/cache-arduino8266

      - name: Build, compile, and analyze memory
        if: steps.check-script.outputs.skip != 'true' && steps.check-tests.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true'
@@ -1505,11 +1585,9 @@ jobs:
        with:
          python-version: ${{ env.DEFAULT_PYTHON }}
          cache-key: ${{ needs.common.outputs.cache-key }}
-      - name: Cache platformio
-        uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
-        with:
-          path: ~/.platformio
-          key: platformio-memory-${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}-${{ hashFiles('platformio.ini') }}
+      - name: Cache the native ESP8266 toolchain
+        if: fromJSON(needs.determine-jobs.outputs.memory_impact).needs_arduino8266
+        uses: ./.github/actions/cache-arduino8266
      - name: Build, compile, and analyze memory
        id: extract
        run: |
@@ -1608,6 +1686,7 @@ jobs:
    needs:
      - common
      - seed-apt-cache
+      - seed-esp8266-native-cache
      - determine-jobs
      - ci-custom
      - pylint
@@ -1623,6 +1702,7 @@ jobs:
      - clang-tidy-esp32-variants
      - test-build-components-split
      - test-esp32-platformio
+      - test-esp8266-native
      - device-builder
      - memory-impact-target-branch
      - memory-impact-pr-branch
@@ -56,7 +56,7 @@ jobs:

      # Initializes the CodeQL tools for scanning.
      - name: Initialize CodeQL
-        uses: github/codeql-action/init@1c5b675653bb5c22dbe9b12b556ec555138e09fd # v4.38.1
+        uses: github/codeql-action/init@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
        with:
          languages: ${{ matrix.language }}
          build-mode: ${{ matrix.build-mode }}
@@ -84,6 +84,6 @@ jobs:
          exit 1

      - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@1c5b675653bb5c22dbe9b12b556ec555138e09fd # v4.38.1
+        uses: github/codeql-action/analyze@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
        with:
          category: "/language:${{matrix.language}}"
@@ -10,7 +10,7 @@ ci:
 repos:
  - repo: https://github.com/astral-sh/ruff-pre-commit
    # Ruff version.
-    rev: v0.16.8
+    rev: v0.16.9
    hooks:
      # Run the linter.
      - id: ruff
@@ -18,7 +18,7 @@ repos:
      # Run the formatter.
      - id: ruff-format
  - repo: https://github.com/PyCQA/flake8
-    rev: 7.3.0
+    rev: 7.4.1
    hooks:
      - id: flake8
        additional_dependencies:
@@ -322,6 +322,25 @@ file does, and it is the authority when they disagree. The most useful starting
              var = await switch.new_switch(config)
          ```

+        - **Optional child entities of a hub:** bind the config once with `sensor.sub_sensors(config)` (or
+          `sub_binary_sensors`, `sub_text_sensors`, `sub_buttons`, `sub_switches`, `sub_numbers`,
+          `sub_selects` in their domains), adding `parent=hub` for entities that derive from `Parented<T>`,
+          then make one call per key, even when there is only one. A call creates the entity only when its key
+          is configured, passes it to the setter and returns it (or `None`); extra arguments such as
+          `min_value` or `options` go on the call. Always name the setter explicitly on the object that owns
+          it, never with `getattr` and an f-string, and keep that variable short (`var` for the component
+          itself, `hub` for one fetched with `cg.get_variable`) so the calls fit on one line. Loops whose
+          setter also takes an index, such as `set_gate_threshold(x, n)`, stay as they are.
+          ```python
+          async def to_code(config):
+              var = cg.new_Pvariable(config[CONF_ID])
+              sensors = sensor.sub_sensors(config)
+              await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+              await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
+              buttons = button.sub_buttons(config, parent=var)
+              await buttons(CONF_RESTART, var.set_restart_button)
+          ```
+
 *   **Automations (Triggers, Actions, Conditions):**

    Automations have three building blocks: **Triggers** (fire when something happens), **Actions** (do something), and **Conditions** (check if something is true).
@@ -125,6 +125,7 @@ esphome/components/combination/* @Cat-Ion @kahrendt
 esphome/components/const/* @esphome/core
 esphome/components/coolix/* @glmnet
 esphome/components/copy/* @OttoWinter
+esphome/components/counter/* @clydebarrow
 esphome/components/cover/* @esphome/core
 esphome/components/cs5460a/* @balrog-kun
 esphome/components/cse7761/* @berfenger
@@ -540,6 +541,7 @@ esphome/components/st7735/* @SenexCrenshaw
 esphome/components/st7789v/* @kbx81
 esphome/components/st7920/* @marsjan155
 esphome/components/statsd/* @Links2004
+esphome/components/stcc4/* @j9brown
 esphome/components/stts22h/* @B48D81EFCC
 esphome/components/substitutions/* @esphome/core
 esphome/components/sun/* @OttoWinter
@@ -553,10 +555,12 @@ esphome/components/syslog/* @clydebarrow
 esphome/components/systa_bus/* @Mat931
 esphome/components/t6615/* @tylermenezes
 esphome/components/tas2780/* @remcom
+esphome/components/tas58xx/* @mrtoy-me @remcom
 esphome/components/tc74/* @sethgirvan
 esphome/components/tca9548a/* @andreashergert1984
 esphome/components/tca9555/* @mobrembski
 esphome/components/tcl112/* @glmnet
+esphome/components/tcp_uart/* @Bascht74
 esphome/components/tee501/* @Stock-M
 esphome/components/teleinfo/* @0hax
 esphome/components/tem3200/* @bakerkj
@@ -598,6 +602,7 @@ esphome/components/uart/button/* @ssieb
 esphome/components/uart/event/* @eoasmxd
 esphome/components/uart/packet_transport/* @clydebarrow
 esphome/components/uart_mux/* @kbx81
+esphome/components/uart_tcp/* @Bascht74
 esphome/components/udp/* @clydebarrow
 esphome/components/ufire_ec/* @pvizeli
 esphome/components/ufire_ise/* @pvizeli
@@ -22,7 +22,7 @@ RUN \
    -r /requirements.txt

 # Install the ESPHome Device Builder dashboard.
-RUN uv pip install --no-cache-dir esphome-device-builder==1.16.0
+RUN uv pip install --no-cache-dir esphome-device-builder==1.19.0

 RUN \
    platformio settings set enable_telemetry No \
@@ -21,10 +21,14 @@ export PLATFORMIO_PLATFORMS_DIR="${pio_cache_base}/platforms"
 export PLATFORMIO_PACKAGES_DIR="${pio_cache_base}/packages"
 export PLATFORMIO_CACHE_DIR="${pio_cache_base}/cache"

-# Keep the native toolchain installs on the persistent cache root, not the
-# container's ephemeral user cache dir (re-downloaded on every restart).
+# Keep the native toolchain installs and compiler caches on the persistent
+# cache root, not the container's user cache dir: it is lost on every
+# restart, and not writable when the container runs as a non-root user.
 export ESPHOME_ESP_IDF_PREFIX="$(dirname "${pio_cache_base}")/idf"
 export ESPHOME_SDK_NRF_PREFIX="$(dirname "${pio_cache_base}")/sdk-nrf"
+export ESPHOME_ARDUINO8266_PREFIX="$(dirname "${pio_cache_base}")/arduino8266"
+export ESPHOME_HOST_PREFIX="$(dirname "${pio_cache_base}")/host"
+export ESPHOME_PLATFORMIO_CCACHE_DIR="$(dirname "${pio_cache_base}")/platformio-ccache"

 # If /build is mounted, use that as the build path
 # otherwise use path in /config (so that builds aren't lost on container restart)
@@ -15,10 +15,14 @@ export PLATFORMIO_PLATFORMS_DIR="${pio_cache_base}/platforms"
 export PLATFORMIO_PACKAGES_DIR="${pio_cache_base}/packages"
 export PLATFORMIO_CACHE_DIR="${pio_cache_base}/cache"

-# Keep the native toolchain installs on the persistent /data volume, not the
-# container's ephemeral user cache dir (wiped on every add-on update/restart).
+# Keep the native toolchain installs and compiler caches on the persistent
+# /data volume, not the container's ephemeral user cache dir (wiped on every
+# add-on update/restart).
 export ESPHOME_ESP_IDF_PREFIX=/data/cache/idf
 export ESPHOME_SDK_NRF_PREFIX=/data/cache/sdk-nrf
+export ESPHOME_ARDUINO8266_PREFIX=/data/cache/arduino8266
+export ESPHOME_HOST_PREFIX=/data/cache/host
+export ESPHOME_PLATFORMIO_CCACHE_DIR=/data/cache/platformio-ccache

 if bashio::config.true 'leave_front_door_open'; then
    export DISABLE_HA_AUTHENTICATION=true
@@ -0,0 +1,8 @@
+esphome:
+  name: docker-test-esp8266-native
+
+esp8266:
+  board: d1_mini
+  toolchain: arduino
+
+logger:
@@ -3,5 +3,7 @@ esphome:

 esp8266:
  board: d1_mini
+  # The PlatformIO path stays covered whatever the default is
+  toolchain: platformio

 logger:
@@ -16,9 +16,8 @@ from typing import TYPE_CHECKING, Protocol
 # 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, platform_hooks
-from esphome.build_helpers.native import native_backend
+from esphome.build_helpers.native import analysis_backend, native_backend
 from esphome.const import (
-    ALLOWED_NAME_CHARS,
    ARGUMENT_HELP_DEVICE,
    BUNDLE_EXTENSION,
    CONF_API,
@@ -36,7 +35,6 @@ from esphome.const import (
    CONF_LOGGER,
    CONF_MDNS,
    CONF_MQTT,
-    CONF_NAME,
    CONF_NAME_ADD_MAC_SUFFIX,
    CONF_OTA,
    CONF_PASSWORD,
@@ -62,6 +60,7 @@ from esphome.stacktrace import LogLineProcessor
 from esphome.types import ConfigType
 from esphome.upload_targets import PortType, get_port_type
 from esphome.util import (
+    ESPHOME_COMMAND,
    PICOTOOL_PACKAGE,
    FlashImage,
    detect_rp2040_bootsel,
@@ -85,7 +84,6 @@ if TYPE_CHECKING:

 _LOGGER = logging.getLogger(__name__)

-ESPHOME_COMMAND = [sys.executable, "-m", "esphome"]

 # Maximum buffer size for serial log reading to prevent unbounded memory growth
 SERIAL_BUFFER_MAX_SIZE = 65536
@@ -150,6 +148,7 @@ class ArgsProtocol(Protocol):
    file: str | None
    no_logs: bool
    only_generate: bool
+    skip_bootloader: bool
    show_secrets: bool
    dashboard: bool
    configuration: str
@@ -829,6 +828,14 @@ def write_cpp_file() -> int:


 def compile_program(args: ArgsProtocol, config: ConfigType) -> int:
+    if CORE.skip_bootloader and not (CORE.is_esp32 and CORE.using_toolchain_esp_idf):
+        # Info, not a warning: an orchestrator cannot see YAML toolchain
+        # overrides, this is its expected no-op, and a full build is safe.
+        _LOGGER.info(
+            "--skip-bootloader ignored: only supported on ESP32 with the "
+            "esp-idf toolchain"
+        )
+        CORE.skip_bootloader = False
    # Keep this gate here, NOT in config validation: device-builder needs
    # `esphome config` to keep succeeding with placeholders so onboarding can run.
    if CONF_WIFI in config:
@@ -838,7 +845,7 @@ def compile_program(args: ArgsProtocol, config: ConfigType) -> int:

    # Keep this here, NOT in codegen: config-hash and --only-generate must keep
    # working on machines that cannot run the toolchain.
-    if CORE.is_esp8266:
+    if CORE.is_esp8266 and CORE.using_toolchain_platformio:
        from esphome.components.esp8266 import check_rosetta

        check_rosetta()
@@ -859,7 +866,10 @@ def compile_program(args: ArgsProtocol, config: ConfigType) -> int:
            return rc

        # Create factory.bin, ota.bin, and firmware.elf copy
-        toolchain.create_factory_bin()
+        if not toolchain.create_factory_bin():
+            # A build whose factory image could not be produced must not
+            # exit 0; downloads would serve an image from an older build.
+            return 1
        toolchain.create_ota_bin()
        toolchain.create_elf_copy()
        from esphome.build_helpers.idedata import warn_if_idedata_missing
@@ -977,8 +987,9 @@ def upload_using_esptool(
        # and partitions included where the target needs them)
        image = native.get_factory_firmware_path()
        if not image.is_file():
+            hint = getattr(native, "missing_image_hint", lambda: None)()
            raise EsphomeError(
-                f"{image} does not exist; compile the configuration first"
+                hint or f"{image} does not exist; compile the configuration first"
            )
        flash_images = [FlashImage(path=image, offset="0x0")]
    else:
@@ -1289,10 +1300,9 @@ def _choose_ota_platform(config: ConfigType, requested: str | None) -> str:
    The native API uses challenge-response auth with MD5/SHA256 hashing of a
    server-issued nonce, so the password is never sent over the wire; the
    ``web_server`` path uses HTTP Basic auth which transmits credentials in
-    cleartext over the LAN. (The native path also supports gzip compression
-    on ESP8266, where flash space is tight; on ESP32/RP2040/LibreTiny the
-    backend reports ``supports_compression() == false`` and the firmware is
-    sent uncompressed regardless of which platform is used.) Falls back to
+    cleartext over the LAN. (The native path also compresses the upload:
+    gzip on ESP8266 and RP2040, which inflate it at reboot, and a deflate
+    stream on ESP32/LibreTiny, which inflate it as it arrives.) Falls back to
    ``web_server`` only when that is the only available platform.
    """
    # Use a dict (insertion-ordered) instead of a list so error messages and
@@ -1381,6 +1391,12 @@ def _upload_via_native_api(
        ota_type = espota2.OTA_TYPE_UPDATE_PARTITION_TABLE
    elif getattr(args, "bootloader", False):
        check_partition_access("--bootloader")
+        if (
+            getattr(args, "file", None) is None
+            and (native := native_backend())
+            and (hint := getattr(native, "missing_image_hint", lambda: None)())
+        ):
+            raise EsphomeError(hint)
        binary = CORE.bootloader_bin
        ota_type = espota2.OTA_TYPE_UPDATE_BOOTLOADER
    if getattr(args, "file", None) is not None:
@@ -1714,26 +1730,12 @@ def command_compile(args: ArgsProtocol, config: ConfigType) -> int | None:
    if exit_code != 0:
        return exit_code
    if CORE.is_host:
-        _LOGGER.info(
-            "Successfully compiled program to path '%s'", _host_program_path(config)
-        )
+        _LOGGER.info("Successfully compiled program to path '%s'", CORE.firmware_bin)
    else:
        _LOGGER.info("Successfully compiled program.")
    return 0


-def _host_program_path(config: ConfigType) -> str:
-    """Return the compiled host ELF path."""
-    if CORE.using_toolchain_esp_idf:
-        from esphome.espidf import toolchain
-
-        return str(toolchain.get_elf_path())
-    from esphome.platformio.toolchain import get_idedata
-
-    # Memoized by compile_program's own call; this is a dict lookup
-    return str(get_idedata(config).firmware_elf_path)
-
-
 def command_upload(args: ArgsProtocol, config: ConfigType) -> int | None:
    # Get devices, resolving special identifiers like OTA
    devices = choose_upload_log_host(
@@ -1770,6 +1772,18 @@ def command_logs(args: ArgsProtocol, config: ConfigType) -> int | None:


 def command_run(args: ArgsProtocol, config: ConfigType) -> int | None:
+    if (
+        CORE.skip_bootloader
+        and CORE.is_esp32
+        and CORE.using_toolchain_esp_idf
+        and any(
+            get_port_type(device) == PortType.SERIAL for device in (args.device or [])
+        )
+    ):
+        # Fail before the compile: the result could never flash over serial.
+        # Elsewhere the flag is ignored, so serial stays fine there.
+        _LOGGER.error("--skip-bootloader builds cannot be flashed over serial")
+        return 1
    exit_code = write_cpp(config)
    if exit_code != 0:
        return exit_code
@@ -1778,7 +1792,7 @@ def command_run(args: ArgsProtocol, config: ConfigType) -> int | None:
        return exit_code
    _LOGGER.info("Successfully compiled program.")
    if CORE.is_host:
-        program_path = _host_program_path(config)
+        program_path = str(CORE.firmware_bin)
        _LOGGER.info("Running program from path '%s'", program_path)
        return run_external_process(program_path)

@@ -2015,8 +2029,8 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
    from esphome.analyze_memory.ram_strings import RamStringsAnalyzer

    # Refuse an unsupported toolchain before paying for a full compile
-    native_toolchain = native_backend()
-    if native_toolchain is None and not CORE.using_toolchain_platformio:
+    analysis_toolchain = analysis_backend()
+    if analysis_toolchain is None and not CORE.using_toolchain_platformio:
        _LOGGER.error(
            "analyze-memory is not supported with the '%s' toolchain on %s; "
            "re-run with --toolchain platformio",
@@ -2024,6 +2038,11 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
            CORE.target_platform,
        )
        return 1
+    if (
+        check_supported := getattr(analysis_toolchain, "check_analysis_supported", None)
+    ) is not None:
+        # Raises with the reason; before the compile, not after it
+        check_supported()

    # Always compile to ensure fresh data (fast if no changes - just relinks)
    exit_code = write_cpp(config)
@@ -2036,9 +2055,9 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:

    # Get idedata for analysis
    idedata = None
-    if native_toolchain is not None:
-        objdump = native_toolchain.get_objdump_path()
-        readelf = native_toolchain.get_readelf_path()
+    if analysis_toolchain is not None:
+        objdump = analysis_toolchain.get_objdump_path()
+        readelf = analysis_toolchain.get_readelf_path()
        for tool in (objdump, readelf):
            if not tool.is_file():
                # The analyzer would silently fall back to host
@@ -2052,7 +2071,7 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
        objdump_path = str(objdump)
        readelf_path = str(readelf)

-        firmware_elf = native_toolchain.get_elf_path()
+        firmware_elf = analysis_toolchain.get_elf_path()
        if not firmware_elf.is_file():
            # The analyzer swallows tool failures, so a missing ELF would
            # produce an exit-0 zeroed report
@@ -2113,155 +2132,9 @@ def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:


 def command_rename(args: ArgsProtocol, config: ConfigType) -> int | None:
-    from esphome import yaml_util
+    from esphome.cli.rename import command_rename as run

-    new_name = args.name
-    for c in new_name:
-        if c not in ALLOWED_NAME_CHARS:
-            safe_print(
-                color(
-                    AnsiFore.BOLD_RED,
-                    f"'{c}' is an invalid character for names. Valid characters are: "
-                    f"{ALLOWED_NAME_CHARS} (lowercase, no spaces)",
-                )
-            )
-            return 1
-    # Load existing yaml file
-    raw_contents = CORE.config_path.read_text(encoding="utf-8")
-
-    yaml = yaml_util.load_yaml(CORE.config_path)
-    if CONF_ESPHOME not in yaml or CONF_NAME not in yaml[CONF_ESPHOME]:
-        safe_print(
-            color(
-                AnsiFore.BOLD_RED, "Complex YAML files cannot be automatically renamed."
-            )
-        )
-        return 1
-    old_name = yaml[CONF_ESPHOME][CONF_NAME]
-    match = re.match(r"^\$\{?([a-zA-Z0-9_]+)\}?$", old_name)
-    if match is None:
-        # Only swap the ``name:`` line that sits directly under the
-        # top-level ``esphome:`` block. A naked ``re.sub`` would
-        # also clobber any other ``name:`` line whose value happens
-        # to match (e.g. a sensor / output / wifi entry sharing the
-        # device's hostname), silently rewriting unrelated user
-        # configuration. The pattern anchors:
-        # - at the start of the line so ``friendly_name:``,
-        #   ``device_name:`` etc. don't match the trailing ``name:``
-        #   substring; and
-        # - at the end of the value (lookahead for whitespace +
-        #   comment + EOL) so ``old_name`` doesn't match as a
-        #   prefix of a longer value (``kitchen`` vs ``kitchen2``).
-        name_pattern = re.compile(
-            rf"^(\s*)name:\s+[\"']?{re.escape(old_name)}[\"']?(?=\s*(?:#|$))"
-        )
-        out_lines: list[str] = []
-        in_esphome_block = False
-        for line in raw_contents.splitlines(keepends=True):
-            if line and not line[0].isspace() and line.strip():
-                in_esphome_block = line.lstrip().startswith("esphome:")
-                out_lines.append(line)
-                continue
-            if in_esphome_block:
-                line = name_pattern.sub(rf'\1name: "{new_name}"', line, count=1)
-            out_lines.append(line)
-        new_raw = "".join(out_lines)
-    else:
-        old_name = yaml[CONF_SUBSTITUTIONS][match.group(1)]
-        if (
-            len(
-                re.findall(
-                    rf"^\s+{match.group(1)}:\s+[\"']?{old_name}[\"']?",
-                    raw_contents,
-                    flags=re.MULTILINE,
-                )
-            )
-            > 1
-        ):
-            safe_print(
-                color(AnsiFore.BOLD_RED, "Too many matches in YAML to safely rename")
-            )
-            return 1
-
-        new_raw = re.sub(
-            rf"^(\s+{match.group(1)}):\s+[\"']?{old_name}[\"']?",
-            f'\\1: "{new_name}"',
-            raw_contents,
-            flags=re.MULTILINE,
-        )
-
-    # ``new_name == old_name`` (after substitution resolution) is
-    # a no-op rewrite that would still queue a pointless re-flash.
-    # Catch it before the path-equality check below — covers the
-    # case where the config filename doesn't match the device name
-    # (e.g. ``weird-file.yaml`` whose ``esphome.name`` is
-    # ``kitchen``; running ``esphome rename weird-file.yaml kitchen``
-    # would otherwise just re-flash the same hostname).
-    if new_name == old_name:
-        safe_print(
-            color(
-                AnsiFore.BOLD_RED,
-                f"'{new_name}' is already the device's name.",
-            )
-        )
-        return 1
-
-    new_path: Path = CORE.config_dir / (new_name + ".yaml")
-    if new_path.resolve() == CORE.config_path.resolve():
-        safe_print(
-            color(
-                AnsiFore.BOLD_RED,
-                f"'{new_name}' is already the device's name.",
-            )
-        )
-        return 1
-    if new_path.exists():
-        safe_print(
-            color(
-                AnsiFore.BOLD_RED,
-                f"Cannot rename: {new_path} already exists. "
-                "Refusing to overwrite an existing configuration.",
-            )
-        )
-        return 1
-    safe_print(
-        f"Updating {color(AnsiFore.CYAN, str(CORE.config_path))} to {color(AnsiFore.CYAN, str(new_path))}"
-    )
-    print()
-
-    new_path.write_text(new_raw, encoding="utf-8")
-
-    rc = run_external_process(*ESPHOME_COMMAND, "config", str(new_path))
-    if rc != 0:
-        safe_print(color(AnsiFore.BOLD_RED, "Rename failed. Reverting changes."))
-        new_path.unlink()
-        return 1
-
-    cli_args = [
-        "run",
-        str(new_path),
-        "--no-logs",
-        "--device",
-        CORE.address,
-    ]
-
-    if args.dashboard:
-        cli_args.insert(0, "--dashboard")
-
-    try:
-        rc = run_external_process(*ESPHOME_COMMAND, *cli_args)
-    except KeyboardInterrupt:
-        rc = 1
-    if rc != 0:
-        new_path.unlink()
-        return 1
-
-    if CORE.config_path != new_path:
-        CORE.config_path.unlink()
-
-    safe_print(color(AnsiFore.BOLD_GREEN, "SUCCESS"))
-    print()
-    return 0
+    return run(args, config)


 PRE_CONFIG_ACTIONS = {
@@ -2296,6 +2169,15 @@ SIMPLE_CONFIG_ACTIONS = [
 ]


+def _add_skip_bootloader_arg(parser: argparse.ArgumentParser) -> None:
+    parser.add_argument(
+        "--skip-bootloader",
+        help="Do not build the bootloader or the factory image; "
+        "the result can only be flashed over OTA.",
+        action="store_true",
+    )
+
+
 def _add_states_args(parser: argparse.ArgumentParser) -> None:
    """Add mutually exclusive ``--states``/``--no-states`` flags to a parser.

@@ -2376,7 +2258,8 @@ def parse_args(argv):
        metavar="{" + ",".join(t.value for t in Toolchain) + "}",
        help=(
            "Select toolchain for compiling. Overrides '<platform>.toolchain' in YAML. "
-            f"Default: {Toolchain.PLATFORMIO.value}."
+            "Default: the platform's native toolchain where it has one, else "
+            f"{Toolchain.PLATFORMIO.value}."
        ),
    )

@@ -2436,6 +2319,7 @@ def parse_args(argv):
        help="Only generate source code, do not compile.",
        action="store_true",
    )
+    _add_skip_bootloader_arg(parser_compile)

    parser_upload = subparsers.add_parser(
        "upload",
@@ -2499,7 +2383,7 @@ def parse_args(argv):
        "-r",
        action="store_true",
        help="Reset the device before starting serial logs.",
-        default=os.getenv("ESPHOME_SERIAL_LOGGING_RESET"),
+        default=get_bool_env("ESPHOME_SERIAL_LOGGING_RESET"),
    )
    _add_states_args(parser_logs)

@@ -2532,6 +2416,7 @@ def parse_args(argv):
    parser_run.add_argument(
        "--no-logs", help="Disable starting logs.", action="store_true"
    )
+    _add_skip_bootloader_arg(parser_run)

    _add_states_args(parser_run)

@@ -2540,7 +2425,7 @@ def parse_args(argv):
        "-r",
        action="store_true",
        help="Reset the device before starting serial logs.",
-        default=os.getenv("ESPHOME_SERIAL_LOGGING_RESET"),
+        default=get_bool_env("ESPHOME_SERIAL_LOGGING_RESET"),
    )
    parser_run.add_argument(
        "--ota-platform",
@@ -2791,6 +2676,7 @@ def run_esphome(argv):

    CORE.config_path = conf_path
    CORE.dashboard = args.dashboard
+    CORE.skip_bootloader = getattr(args, "skip_bootloader", False)
    if args.toolchain is not None:
        # CLI toolchain wins over esp32.toolchain in YAML.
        CORE.toolchain = args.toolchain
@@ -148,6 +148,13 @@ class AddressCache:
                continue
            hostname, ips = arg.split("=", 1)
            # Normalize hostname for consistent lookups
-            normalized = normalize_hostname(hostname)
-            cache[normalized] = [ip.strip() for ip in ips.split(",")]
+            normalized = normalize_hostname(hostname.strip())
+            addresses = [ip for value in ips.split(",") if (ip := value.strip())]
+            if not normalized or not addresses:
+                _LOGGER.warning(
+                    "Invalid cache entry: %s (hostname and at least one address are required)",
+                    arg,
+                )
+                continue
+            cache[normalized] = addresses
        return cache
@@ -37,7 +37,7 @@ def find_elf_path(build_path: Path) -> Path | None:
    """
    name = build_path.name
    for candidate in (
-        # Native ESP-IDF: idf.py writes build/<name>.elf, which ESPHome copies
+        # Native ESP-IDF: the build writes build/<name>.elf, which ESPHome copies
        # to build/firmware.elf (see espidf.toolchain.create_elf_copy)
        build_path / "build" / "firmware.elf",
        # PlatformIO
@@ -2,7 +2,9 @@

 Bundled names build straight from the framework tree; everything else goes
 through ``esphome.platformio.library``. Mirrors ``lib_ldf_mode=off``: each
-library builds its own archive; all include dirs join one global path.
+library builds its own archive; all include dirs join one global path. The
+host build reuses it without a framework tree: nothing is bundled there and
+every name resolves from the registry.

 Deviations from PlatformIO: flat-layout libraries get the recursive default
 source filter; ``dot_a_linkage`` is honored; bundled libraries never run a
@@ -342,13 +344,24 @@ def _check_unfulfilled_provides(


 def resolve_libraries(
-    framework_path: Path, *, pio_platform: str, board_mcu: str, cache_key: str
+    framework_path: Path | None,
+    *,
+    pio_platform: str,
+    board_mcu: str,
+    cache_key: str,
+    framework: str | None = "arduino",
+    manifest_optional: bool = False,
 ) -> list[ArduinoLibrary]:
    """Resolve every ``cg.add_library()`` entry into an :class:`ArduinoLibrary`.

    ``pio_platform``/``board_mcu`` filter manifests the way PlatformIO would
    for that core (e.g. ``espressif8266``/``esp8266``); ``cache_key`` keys the
-    shared converter's download cache.
+    shared converter's download cache. ``framework`` is the manifest
+    framework token the compatibility check warns about; None skips it.
+    A None ``framework_path`` means no core-bundled libraries exist (the
+    host build): every name resolves from the registry.
+    ``manifest_optional`` accepts libraries without a manifest, built with
+    PlatformIO's default layout.

    The returned list is not topologically sorted, so the caller must link
    the archives inside one ``--start-group``/``--end-group`` pair (the
@@ -359,18 +372,22 @@ def resolve_libraries(
    # PlatformIO's lib_ignore covers framework-bundled libraries too; the
    # shared converter only filters the registry/git ones.
    lib_ignore = lib_ignore_set()
-    # Exact directory names keep membership case-sensitive everywhere
-    # (an is_dir() probe would match "wire" on macOS/Windows and build
-    # the bundled Wire twice)
-    libraries_dir = framework_path / "libraries"
-    if not libraries_dir.is_dir():
-        # A registry fallback would fail later with a misleading
-        # package-not-found error per bundled name
-        raise EsphomeError(
-            f"{libraries_dir} is missing; the framework install may be "
-            "incomplete (run 'esphome clean-all')"
+    bundled_dir_names: frozenset[str] = frozenset()
+    if framework_path is not None:
+        # Exact directory names keep membership case-sensitive everywhere
+        # (an is_dir() probe would match "wire" on macOS/Windows and build
+        # the bundled Wire twice)
+        libraries_dir = framework_path / "libraries"
+        if not libraries_dir.is_dir():
+            # A registry fallback would fail later with a misleading
+            # package-not-found error per bundled name
+            raise EsphomeError(
+                f"{libraries_dir} is missing; the framework install may be "
+                "incomplete (run 'esphome clean-all')"
+            )
+        bundled_dir_names = frozenset(
+            p.name for p in libraries_dir.iterdir() if p.is_dir()
        )
-    bundled_dir_names = frozenset(p.name for p in libraries_dir.iterdir() if p.is_dir())

    def _provided(name: object) -> bool:
        return _is_safe_library_name(name) and name in bundled_dir_names
@@ -497,12 +514,13 @@ def resolve_libraries(

    backend = LibraryBackend(
        platform=pio_platform,
-        framework="arduino",
+        framework=framework,
        emit=_emit,
        cache_key=cache_key,
        # The walk must not resolve bundled names from the registry;
        # _add_bundled_dependencies adds them after emit
        provides=_provided,
+        manifest_optional=manifest_optional,
    )
    if external:
        convert_libraries(external, backend)
@@ -3,12 +3,12 @@
 Artifacts land in a machine-global cache (shared across projects, like the
 ESP-IDF install in ``esphome.espidf.framework``):

-    <cache>/arduino8266/frameworks/<version>/   framework-arduinoespressif8266
-    <cache>/arduino8266/toolchains/<version>/   toolchain-xtensa (gcc 10.3)
+    <cache>/arduino8266/frameworks/<tag>/   the Arduino core
+    <cache>/arduino8266/toolchains/<tag>/   xtensa-lx106-elf gcc 10.3

-Packages come from the PlatformIO registry (identical bits to the PlatformIO
-backend); ``ESPHOME_ARDUINO8266_*_MIRRORS`` overrides the URLs. ninja comes
-from PATH or the ninja PyPI wheel.
+Both come from esphome-libs releases pinned below;
+``ESPHOME_ARDUINO8266_*_MIRRORS`` overrides the URLs, with ``{VERSION}``
+standing for the release tag. ninja comes from PATH or the ninja PyPI wheel.
 """

 from __future__ import annotations
@@ -17,18 +17,74 @@ import os
 from pathlib import Path
 from typing import NamedTuple

-from esphome.build_helpers.ccache import ccache_defaults_env
+from esphome.build_helpers.ccache import ccache_env
 from esphome.build_helpers.ninja import find_ninja
 from esphome.build_helpers.tools_cache import ARDUINO8266_TOOLS_CACHE, tools_cache_path
 from esphome.core import EsphomeError, Version
 from esphome.framework_helpers import str_to_lst_of_str
-from esphome.platformio.registry import install_package, prefetch_packages
+from esphome.platformio.registry import (
+    Download,
+    PackageSpec,
+    Resolver,
+    get_systype,
+    install_packages,
+    prefetch_packages,
+)

-FRAMEWORK_PACKAGE = "framework-arduinoespressif8266"
-TOOLCHAIN_PACKAGE = "toolchain-xtensa"
+FRAMEWORK_PACKAGE = "arduino-esp8266"
+_FRAMEWORK_RELEASES = "https://github.com/esphome-libs/arduino-esp8266/releases/"
+
+
+class FrameworkRelease(NamedTuple):
+    tag: str
+    sha256: str
+    size: int
+
+    def download(self) -> Download:
+        archive = f"{FRAMEWORK_PACKAGE}-{self.tag}.tar.gz"
+        url = f"{_FRAMEWORK_RELEASES}download/{self.tag}/{archive}"
+        return Download(url, self.sha256, self.size)
+
+
+# Arduino core version -> its build in esphome-libs/arduino-esp8266
+FRAMEWORK_RELEASES: dict[Version, FrameworkRelease] = {
+    Version(3, 1, 2): FrameworkRelease(
+        "3.1.2-esphome.1",
+        "e80751e3123676b967143e39c61f2d8693946db4c7806f2a83dcaaf797ecd582",
+        37189311,
+    ),
+}
+
+TOOLCHAIN_PACKAGE = "toolchain-xtensa-lx106-elf"
 # gcc 10.3, the toolchain Arduino core 3.x builds with; the build
 # generator's compile flags are tuned to it.
-TOOLCHAIN_VERSION = "2.100300.220621"
+TOOLCHAIN_VERSION = "10.3.0-esphome.2"
+_TOOLCHAIN_RELEASES = (
+    "https://github.com/esphome-libs/xtensa-lx106-elf-toolchain/releases/"
+)
+# Registry system tag -> (sha256, size) of that host's archive
+TOOLCHAIN_BUILDS: dict[str, tuple[str, int]] = {
+    "darwin_arm64": (
+        "849cede44d4d5c6ea0f14099783239f559f46327bea314281814f2652b486201",
+        60830321,
+    ),
+    "darwin_x86_64": (
+        "ca69904daabf0c5983b372423e5e62f49182a793e992c052e94666852470c897",
+        64149487,
+    ),
+    "linux_aarch64": (
+        "60a49a4f082bf246544bd409a9517dbbcab19bb30ac9decbee544b896aaccbd6",
+        67573397,
+    ),
+    "linux_x86_64": (
+        "1fba33ca1494ec79f2776e0e37eca93282d30f8bb9992f5f4f9a655d6fff1db4",
+        68431336,
+    ),
+    "windows_amd64": (
+        "af9066b0e5bf036f04f2bd9d08b89b81a7f183c57dac0abcaff71dd861cf5f3b",
+        67664137,
+    ),
+}

 ESPHOME_ARDUINO8266_FRAMEWORK_MIRRORS = str_to_lst_of_str(
    os.environ.get("ESPHOME_ARDUINO8266_FRAMEWORK_MIRRORS", "")
@@ -44,36 +100,40 @@ def get_arduino8266_tools_path() -> Path:
    return tools_cache_path(*ARDUINO8266_TOOLS_CACHE)


-# 3.1.1 rather than 3.1.0: the registry has no packages for 3.0.0, 3.0.1 or 3.1.0
-MIN_FRAMEWORK_VERSION = Version(3, 1, 1)
-
-
-def framework_package_version(ver: Version) -> str:
-    """Map an Arduino core version to its registry package version (3.1.2 ->
-    3.30102.0; the leading 3 is the package major).
-
-    Exact registry names for 3.x cores; callers floor at MIN_FRAMEWORK_VERSION.
-    """
-    if ver.major > 3:
+def framework_release(version: Version) -> FrameworkRelease:
+    if (release := FRAMEWORK_RELEASES.get(version)) is None:
        raise EsphomeError(
-            f"Arduino core {ver} is not supported yet; "
-            "the newest known core series is 3.x"
+            f"'toolchain: arduino' has no build of Arduino core {version}; "
+            f"available: {', '.join(str(v) for v in FRAMEWORK_RELEASES)}. "
+            "Use one of those or 'toolchain: platformio'"
        )
-    if ver.major < 3:
-        raise EsphomeError(
-            f"Arduino core {ver} is not supported; ESPHome requires core 3.x"
-        )
-    return f"3.{ver.major}{ver.minor:02d}{ver.patch:02d}.0"
+    return release


-def get_framework_path(package_version: str) -> Path:
-    return get_arduino8266_tools_path() / "frameworks" / package_version
+def get_framework_path(tag: str) -> Path:
+    return get_arduino8266_tools_path() / "frameworks" / tag


 def get_toolchain_path() -> Path:
    return get_arduino8266_tools_path() / "toolchains" / TOOLCHAIN_VERSION


+def toolchain_download() -> Download:
+    """The toolchain archive for the current host."""
+    systype = get_systype()
+    if (build := TOOLCHAIN_BUILDS.get(systype)) is None:
+        raise EsphomeError(
+            f"There is no ESP8266 toolchain for this system ({systype}); "
+            f"supported systems are {', '.join(sorted(TOOLCHAIN_BUILDS))}. "
+            "Either set 'toolchain: platformio' under 'esp8266:', or point "
+            "ESPHOME_ARDUINO8266_TOOLCHAIN_MIRRORS at a toolchain archive"
+        )
+    sha256, size = build
+    archive = f"{TOOLCHAIN_PACKAGE}-{TOOLCHAIN_VERSION}-{systype}.tar.gz"
+    url = f"{_TOOLCHAIN_RELEASES}download/{TOOLCHAIN_VERSION}/{archive}"
+    return Download(url, sha256, size)
+
+
 class InstalledPaths(NamedTuple):
    """Locations of the installed framework, toolchain, and ninja binary."""

@@ -84,29 +144,22 @@ class InstalledPaths(NamedTuple):

 def check_and_install(framework_version: Version) -> InstalledPaths:
    """Ensure framework, toolchain, and ninja are installed; return their paths."""
-    if framework_version < MIN_FRAMEWORK_VERSION:
-        # Config validation enforces this too; keep the module honest when
-        # called directly.
-        raise EsphomeError(
-            f"The native toolchain requires the Arduino core "
-            f">= {MIN_FRAMEWORK_VERSION}, got {framework_version}"
-        )
+    release = framework_release(framework_version)
    # Probe the cheap local dependency before ~110 MB of downloads
    ninja_path = find_ninja()
-    package_version = framework_package_version(framework_version)
-    framework_path = get_framework_path(package_version)
+    framework_path = get_framework_path(release.tag)
    downloads_dir = get_arduino8266_tools_path() / "downloads"
    toolchain_path = get_toolchain_path()
    # One spec per package: the prefetch and the installs must agree
    specs = (
-        (
+        PackageSpec(
            FRAMEWORK_PACKAGE,
-            package_version,
+            release.tag,
            framework_path,
            ESPHOME_ARDUINO8266_FRAMEWORK_MIRRORS,
            ("cores/esp8266", "tools/sdk", "libraries"),
        ),
-        (
+        PackageSpec(
            TOOLCHAIN_PACKAGE,
            TOOLCHAIN_VERSION,
            toolchain_path,
@@ -115,10 +168,17 @@ def check_and_install(framework_version: Version) -> InstalledPaths:
            ("bin", "xtensa-lx106-elf"),
        ),
    )
-    # Fetch both archives at once; the installs below verify and extract
-    prefetch_packages([spec[:4] for spec in specs], downloads_dir)
-    for name, version, dest, mirrors, expect in specs:
-        install_package(name, version, dest, mirrors, downloads_dir, expect=expect)
+    # Resolved only when a download is needed, so an installed toolchain
+    # keeps working on a host without a build; a mirror override wins
+    resolvers: dict[str, Resolver] = {}
+    if not ESPHOME_ARDUINO8266_FRAMEWORK_MIRRORS:
+        resolvers[FRAMEWORK_PACKAGE] = release.download
+    if not ESPHOME_ARDUINO8266_TOOLCHAIN_MIRRORS:
+        resolvers[TOOLCHAIN_PACKAGE] = toolchain_download
+    # Fetch both archives at once; the installs verify and extract them.
+    # One spec list for both, so the two phases cannot drift.
+    prefetch_packages(specs, downloads_dir, resolvers)
+    install_packages(specs, downloads_dir, resolvers)
    return InstalledPaths(
        framework=framework_path, toolchain=toolchain_path, ninja=ninja_path
    )
@@ -143,17 +203,5 @@ def get_build_env(toolchain_path: Path, ccache: str | None) -> dict[str, str]:
        *filter(None, env.get("PATH", "").split(os.pathsep)),
    ]
    env["PATH"] = os.pathsep.join(parts)
-    env.update(ccache_env(ccache))
+    env.update(ccache_env(ccache, ARDUINO8266_TOOLS_CACHE))
    return env
-
-
-def ccache_env(ccache: str | None) -> dict[str, str]:
-    """Return ccache settings for the build subprocess (not os.environ).
-
-    ``ccache`` is the pre-resolved binary (resolve_ccache_path), or None
-    when disabled. Values the user already set in the environment are
-    respected.
-    """
-    if ccache is None:
-        return {}
-    return ccache_defaults_env(get_arduino8266_tools_path() / "ccache")
@@ -2,21 +2,21 @@

 from __future__ import annotations

-import json
 import logging
 from pathlib import Path
 import subprocess
 from typing import TYPE_CHECKING

-from esphome.build_helpers.ccache import resolve_ccache_path
+from esphome.build_helpers.ccache import resolve_absolute_ccache_path
+from esphome.build_helpers.native import warn_ignored_platformio_options
+from esphome.build_helpers.ninja import refresh_compile_commands
 from esphome.const import (
    CONF_COMPILE_PROCESS_LIMIT,
    CONF_ESPHOME,
    KEY_CORE,
    KEY_FRAMEWORK_VERSION,
 )
-from esphome.core import CORE, EsphomeError
-from esphome.helpers import write_file
+from esphome.core import CORE
 from esphome.types import ConfigType

 if TYPE_CHECKING:
@@ -28,20 +28,6 @@ _LOGGER = logging.getLogger(__name__)
 _MAX_RAM_SIZE = 81920


-def _warn_ignored_platformio_options() -> None:
-    """Warn for component-added platformio options the native build drops."""
-    from esphome.core.config import NATIVE_ARDUINO_CONSUMED_PIO_OPTIONS
-
-    consumed = NATIVE_ARDUINO_CONSUMED_PIO_OPTIONS
-    for key in sorted(CORE.platformio_options or {}):
-        if key not in consumed:
-            _LOGGER.warning(
-                "platformio_options->%s is ignored when building with the "
-                "native 'arduino' toolchain",
-                key,
-            )
-
-
 _RAM_SECTIONS = (".data", ".rodata", ".bss")
 _FLASH_SECTIONS = (".irom0.text", ".text", ".text1", ".data", ".rodata")

@@ -84,21 +70,17 @@ def get_readelf_path() -> Path:
 def run_compile(config: ConfigType, verbose: bool) -> int:
    from esphome.arduino8266 import framework
    from esphome.build_gen import arduino8266 as build_gen
+    from esphome.core.config import NATIVE_ARDUINO_CONSUMED_PIO_OPTIONS

-    _warn_ignored_platformio_options()
+    warn_ignored_platformio_options(NATIVE_ARDUINO_CONSUMED_PIO_OPTIONS)
    paths = framework.check_and_install(CORE.data[KEY_CORE][KEY_FRAMEWORK_VERSION])
    # Resolved once: the probe is not free and three consumers need it
-    ccache = resolve_ccache_path()
-    build_gen.write_project(paths, ccache)
+    ccache = resolve_absolute_ccache_path()
+    ninja_changed = build_gen.write_project(paths, ccache)

    build_dir = get_build_dir()
    env = framework.get_build_env(paths.toolchain, ccache)
-
-    # The DB is a pure function of build.ninja; regenerate when it is older
-    compdb = build_dir / "compile_commands.json"
-    ninja_file = build_dir / "build.ninja"
-    if not compdb.is_file() or compdb.stat().st_mtime < ninja_file.stat().st_mtime:
-        _write_compile_commands(paths.ninja, build_dir, env)
+    refresh_compile_commands(paths.ninja, build_dir, env, ninja_changed)

    cmd = [str(paths.ninja)]
    if verbose:
@@ -140,42 +122,6 @@ def run_compile(config: ConfigType, verbose: bool) -> int:
    return 0


-def _write_compile_commands(
-    ninja_path: Path, build_dir: Path, env: dict[str, str]
-) -> None:
-    compdb = build_dir / "compile_commands.json"
-    result = subprocess.run(
-        [str(ninja_path), "-C", str(build_dir), "-t", "compdb", "c", "cxx", "asm"],
-        env=env,
-        capture_output=True,
-        text=True,
-        check=False,
-        close_fds=False,
-    )
-    if result.returncode != 0:
-        # Drop any stale database so consumers (IDE integration, clang-tidy,
-        # the memory analyzer) can't silently read outdated data.
-        compdb.unlink(missing_ok=True)
-        raise EsphomeError(f"Could not generate compile_commands.json: {result.stderr}")
-    try:
-        entries = json.loads(result.stdout)
-    except ValueError as err:
-        compdb.unlink(missing_ok=True)
-        raise EsphomeError(
-            f"ninja produced an unparsable compile database: {err} "
-            f"(output starts {result.stdout[:120]!r})"
-        ) from err
-    if not entries:
-        # compdb exits 0 with [] for unknown rule names; a renamed compile
-        # rule must fail the build, not silently strand every consumer
-        compdb.unlink(missing_ok=True)
-        raise EsphomeError(
-            "ninja produced an empty compile database; the generator's rule "
-            "names no longer match"
-        )
-    write_file(compdb, result.stdout)
-
-
 def _parse_app_size(build_dir: Path, paths: InstalledPaths) -> int | None:
    """Read the app flash budget (irom0_0_seg length) from the linker script."""
    from esphome.build_gen.arduino8266 import get_flash_ld_path
@@ -253,7 +199,7 @@ def get_idedata(ccache: str | None = None) -> dict | None:

    # A disabled ccache resolves to None without spawning anything, so
    # re-resolving here costs nothing when the caller has no answer
-    launcher = ccache or resolve_ccache_path()
+    launcher = ccache or resolve_absolute_ccache_path()
    return load_or_build_idedata(
        get_build_dir() / "compile_commands.json",
        get_elf_path(),
@@ -345,14 +345,28 @@ async def _apply_parent(config: ConfigType, id_key: str = CONF_ID) -> str:


 def _apply_lambda_args(args: TemplateArgsType) -> TemplateArgsType:
-    # Must match ApplyAction::ApplyFn and ApplyCondition::CheckFn exactly for the function
-    # pointer conversion.
+    # The generated function's parameters; a std::string arg is never copied.
    return [
        (cg.RawExpression(f"const std::remove_cvref_t<{cg.safe_exp(t)}> &"), arg)
        for t, arg in args
    ]


+def _apply_function(
+    id_: ID,
+    return_type: SafeExpType,
+    template_arg: cg.TemplateArguments,
+    lambda_args: TemplateArgsType,
+    statements: list[str],
+) -> MockObj:
+    """Emit the generated function and declare ``id_`` as the ``ApplyAction`` or
+    ``ApplyCondition`` templated on it, so ``play()`` calls it directly."""
+    fn = cg.static_function(
+        f"esphome__{id_.id}__fn", return_type, lambda_args, statements
+    )
+    return cg.new_Pvariable(id_, cg.TemplateArguments(fn, *template_arg))
+
+
 async def _render_values(
    name: str,
    target: str,
@@ -403,8 +417,8 @@ def register_apply_action(
 ) -> None:
    """Register an action that only forwards config values to its parent, with no C++ class.

-    Generates one stateless function for ``ApplyAction<Ts...>``: the parent (read from
-    ``id_key``) and constants are baked in, lambdas are called inline with the trigger args.
+    Generates one static function with the parent (read from ``id_key``) and constants baked
+    in, lambdas called inline with the trigger args, and an ``ApplyAction`` templated on it.
    A constant that is an id (``cv.use_id`` under ``cv.templatable``) is the object it names.
    With ``call`` every statement targets the call object ``auto apply_call = parent->call()``,
    and ``apply_call.perform()`` is appended.
@@ -449,10 +463,9 @@ def register_apply_action(
                *statements,
                "apply_call.perform();",
            ]
-        apply_lambda = LambdaExpression(
-            ["\n".join(statements)], lambda_args, capture="", return_type=cg.void
+        return _apply_function(
+            action_id, cg.void, template_arg, lambda_args, statements
        )
-        return cg.new_Pvariable(action_id, template_arg, apply_lambda)

    register_action(name, ApplyAction, schema, synchronous=True)(builder)

@@ -466,7 +479,7 @@ def register_apply_condition(
    ``ApplyCall`` such as ``ApplyCall("state == {}", ((CONF_STATE, cg.bool_),))`` compares
    against config values, all of which must be present. Write ``== false`` to negate.
    String constants are plain literals, so compare a ``std::string`` or ``StringRef`` member.
-    Generates one stateless function for ``ApplyCondition<Ts...>``.
+    Generates one static predicate and an ``ApplyCondition`` templated on it.
    """
    call = check if isinstance(check, ApplyCall) else ApplyCall(check)
    members = call.members
@@ -492,13 +505,13 @@ def register_apply_condition(
            lambda_args,
            compare=True,
        )
-        check_lambda = LambdaExpression(
-            [f"return {parent}->{call.target.format(*exprs)};"],
+        return _apply_function(
+            condition_id,
+            cg.bool_,
+            template_arg,
            lambda_args,
-            capture="",
-            return_type=cg.bool_,
+            [f"return {parent}->{call.target.format(*exprs)};"],
        )
-        return cg.new_Pvariable(condition_id, template_arg, check_lambda)

    register_condition(name, ApplyCondition, schema)(builder)

@@ -14,7 +14,6 @@ from the build flags with the same precedence as the PlatformIO builder.

 from __future__ import annotations

-from collections.abc import Collection
 from dataclasses import dataclass
 import hashlib
 import logging
@@ -23,15 +22,26 @@ from pathlib import Path
 import re
 import shlex
 import subprocess
-import sys
 from typing import TYPE_CHECKING, NamedTuple

 from esphome.arduino8266.framework import toolchain_tool
+from esphome.build_helpers.idedata import is_joined_include
 from esphome.build_helpers.ninja import (
    escape as _e,
    quote_path as _q,
    shell_token as _shell_token,
 )
+from esphome.build_helpers.ninja_gen import (
+    ar_rule_lines,
+    collect_sources,
+    compile_edges,
+    compile_rule_lines,
+    library_edges,
+    pch_edges,
+    pch_rule_lines,
+    tool_lines,
+)
+from esphome.build_helpers.pch import PCH_DEFAULT_HEADERS
 from esphome.components.esp8266 import build_surgery
 from esphome.components.esp8266.boards import (
    BOARDS,
@@ -46,12 +56,9 @@ from esphome.components.esp8266.const import (
    KEY_SCANF_FLOAT,
 )
 from esphome.core import CORE, EsphomeError
-from esphome.framework_helpers import (
-    get_project_cxx_compile_flags,
-    strip_win_long_path_prefix,
-)
+from esphome.framework_helpers import get_project_cxx_compile_flags
 from esphome.helpers import mkdir_p, write_file_if_changed
-from esphome.platformio.library import SOURCE_KIND_FOR_SUFFIX, lex_build_flags
+from esphome.platformio.library import lex_build_flags

 if TYPE_CHECKING:
    from esphome.arduino8266.framework import InstalledPaths
@@ -643,14 +650,6 @@ _PLAIN_LINKER_PREFIXES = ("-T", "-Xlinker")
 _PLAIN_DRIVER_LINK_PREFIXES = ("-fuse-ld=", "--specs=", "-specs=")


-def _collect_sources(root: Path, exclude: Collection[str] = frozenset()) -> list[Path]:
-    return sorted(
-        p
-        for p in root.rglob("*")
-        if p.suffix in SOURCE_KIND_FOR_SUFFIX and p.name not in exclude
-    )
-
-
 def _stat_sig(path: Path) -> str:
    """Size and mtime cache-stamp signature for one input file.

@@ -868,34 +867,6 @@ def _generate_testing_flash_ld(
    )


-def _ninja_compile_edges(
-    lines: list[str],
-    sources: list[Path],
-    root: Path,
-    group: str,
-    flags: str = "",
-) -> list[str]:
-    """Emit compile edges for ``sources``; return the object paths."""
-    objects = []
-    for src in sources:
-        rel = src.relative_to(root).as_posix()
-        obj = f"obj/{group}/{rel}.o"
-        escaped_obj = _e(obj)
-        lines.append(
-            f"build {escaped_obj}: {SOURCE_KIND_FOR_SUFFIX[src.suffix]} {_e(src)}"
-        )
-        if flags:
-            lines.append(f"  flags = {flags}")
-        # Escaped once here: the returned paths only ever appear in build
-        # statements (archive/link inputs), which use ninja escaping.
-        objects.append(escaped_obj)
-    return objects
-
-
-def _common_parent(paths: list[Path]) -> Path:
-    return Path(os.path.commonpath([str(p.parent) for p in paths]))
-
-
 class _FlagSets(NamedTuple):
    cflags: list[str]
    cxxflags: list[str]
@@ -1082,58 +1053,22 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
        + ["stdc++-exc" if config.exceptions else "stdc++", "m", "c", "gcc"]
    )

-    build_tool = Path(__file__).parent / "build_tool.py"
-
-    # $in/$out stay unquoted: ninja escapes its built-in path variables
-    # itself; only literal paths need _q().
+    cxx = (toolchain_tool(paths.toolchain, "g++"),)
    lines = [
-        "# Auto-generated by ESPHome",
-        "ninja_required_version = 1.5",
-        f"cc = {_q(toolchain_tool(paths.toolchain, 'gcc'))}",
-        f"cxx = {_q(toolchain_tool(paths.toolchain, 'g++'))}",
-        # The NSIS launcher starts Python with a \\?\ extended-length path
-        # that cmd.exe cannot spawn; same strip every other emitted binary
-        # path gets
-        f"python = {_q(strip_win_long_path_prefix(sys.executable))}",
-        f"buildtool = {_q(build_tool)}",
-        f"ccache = {_q(ccache) if ccache else ''}",
-        "",
-        # Rule names match SOURCE_KIND_FOR_SUFFIX values (c, cxx, asm, aspp)
-        "rule c",
-        "  command = $ccache $cc -MMD -MF $out.d $cflags $flags -c $in -o $out",
-        "  depfile = $out.d",
-        "  deps = gcc",
-        "  description = CC $out",
-        "rule cxx",
-        "  command = $ccache $cxx -MMD -MF $out.d $cxxflags $flags -c $in -o $out",
-        "  depfile = $out.d",
-        "  deps = gcc",
-        "  description = CXX $out",
-        "rule aspp",
-        "  command = $ccache $cc -MMD -MF $out.d -x assembler-with-cpp $asflags $flags -c $in -o $out",
-        "  depfile = $out.d",
-        "  deps = gcc",
-        "  description = AS $out",
-        # Plain assembler, as SCons's ASCOM: no preprocessor, so no
-        # depfile and no $flags (defines/includes) either
-        "rule asm",
-        "  command = $ccache $cc -x assembler $asflags -c $in -o $out",
-        "  description = AS $out",
-        "rule ar",
-        f"  command = $python $buildtool ar {_q(toolchain_tool(paths.toolchain, 'ar'))} $out $out.rsp",
-        "  rspfile = $out.rsp",
-        "  rspfile_content = $in_newline",
-        "  description = AR $out",
+        *tool_lines((toolchain_tool(paths.toolchain, "gcc"),), cxx, ccache),
+        *compile_rule_lines(),
+        *ar_rule_lines(toolchain_tool(paths.toolchain, "ar")),
+        *pch_rule_lines(),
        "rule link",
        "  command = $cxx -o $out $linkflags @$out.rsp $libdirflags -Wl,--start-group $archives $libflags -Wl,--end-group",
        "  rspfile = $out.rsp",
        "  rspfile_content = $in_newline",
        "  description = LINK $out",
        "rule elf2bin",
-        # --flash_size deliberately stays board-derived, as under
-        # PlatformIO (which reads upload.maximum_size, not the ldscript).
+        # --flash_size follows PlatformIO: ldscript filename first, then
+        # upload.maximum_size, so the header always matches the layout.
        # -W: the framework's own elf2bin.py trips SyntaxWarning on 3.12+.
-        f"  command = $python -W ignore::SyntaxWarning {_q(framework / 'tools' / 'elf2bin.py')} --eboot {_q(framework / 'bootloaders' / 'eboot' / 'eboot.elf')} --app $in --flash_mode {flash_mode} --flash_freq {_FLASH_FREQ_MHZ} --flash_size {_flash_size_str(BOARDS[board][KEY_FLASH_SIZE])} --path {_q(toolchain_bin)} --out $out",
+        f"  command = $python -W ignore::SyntaxWarning {_q(framework / 'tools' / 'elf2bin.py')} --eboot {_q(framework / 'bootloaders' / 'eboot' / 'eboot.elf')} --app $in --flash_mode {flash_mode} --flash_freq {_FLASH_FREQ_MHZ} --flash_size {_elf2bin_flash_size(board, flash_ld_name)} --path {_q(toolchain_bin)} --out $out",
        "  description = BIN $out",
        "rule copy",
        "  command = $python $buildtool copy $in $out",
@@ -1153,16 +1088,15 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
        core_exclude |= _CORE_EXCLUDE_WAVEFORM

    archives = []
-    direct_objs: list[str] = []
    # variant_dir existence was already enforced with the include dirs
-    variant_sources = _collect_sources(variant_dir)
+    variant_sources = collect_sources(variant_dir)
    if variant_sources:
-        objs = _ninja_compile_edges(lines, variant_sources, variant_dir, "variant")
+        objs = compile_edges(lines, variant_sources, variant_dir, "variant")
        lines.append(f"build libFrameworkArduinoVariant.a: ar {' '.join(objs)}")
        archives.append("libFrameworkArduinoVariant.a")

-    core_objs = _ninja_compile_edges(
-        lines, _collect_sources(core_dir, core_exclude), core_dir, "core"
+    core_objs = compile_edges(
+        lines, collect_sources(core_dir, core_exclude), core_dir, "core"
    )
    if not core_objs:
        # An empty archive would link into a wall of undefined references
@@ -1173,37 +1107,14 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
    lines.append(f"build libFrameworkArduino.a: ar {' '.join(core_objs)}")
    archives.append("libFrameworkArduino.a")

-    for lib in libraries:
-        if not lib.sources:
-            # Header-only libraries are legitimate; the log makes an empty
-            # srcFilter or broken tree traceable before link errors do.
-            _LOGGER.debug(
-                "Library %s has no source files; contributing includes only",
-                lib.name,
-            )
-            continue
-        lib_root = _common_parent(lib.sources)
-        objs = _ninja_compile_edges(
-            lines,
-            lib.sources,
-            lib_root,
-            f"lib/{lib.name}",
-            flags=" ".join(_shell_token(f) for f in lib.flags),
-        )
-        if not lib.lib_archive:
-            # libArchive: false / dot_a_linkage=false: hand the objects to
-            # the linker directly so unreferenced-but-required symbols
-            # (exception handlers, weak overrides) survive
-            direct_objs.extend(objs)
-            continue
-        archive = f"lib{lib.name}.a"
-        lines.append(f"build {_e(archive)}: ar {' '.join(objs)}")
-        archives.append(archive)
+    lib_archives, direct_objs = library_edges(lines, libraries)
+    archives += lib_archives

    # One source of truth with the PlatformIO path: esp8266/__init__ pins
    # build_src_flags (the throw_stubs force-include); -include paths
    # resolve against the source root
-    src_parts: list[str] = []
+    src_other: list[str] = []
+    src_includes: list[str] = []
    src_it = iter(
        lex_build_flags(_pio_option("build_src_flags", ""), "build_src_flags")
    )
@@ -1214,15 +1125,33 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
                raise EsphomeError(
                    "build_src_flags has a trailing '-include' with no header"
                )
-            src_parts.append(f"-include {_q(src_dir / header)}")
+            src_includes.append(header)
+        elif is_joined_include(tok):
+            # Left in src_other it would precede the pch include
+            src_includes.append(tok[len("-include") :])
        else:
-            src_parts.append(_shell_token(tok))
-    src_extra = " ".join(src_parts)
+            src_other.append(_shell_token(tok))
+    include_flags = [f"-include {_q(src_dir / h)}" for h in src_includes]
    # One shared variable instead of repeating the flags line on every src
    # edge (hundreds of edges in a real project)
-    lines.append(f"srcflags = {src_extra}")
-    src_objs = _ninja_compile_edges(
-        lines, _collect_sources(src_dir), src_dir, "src", flags="$srcflags"
+    lines.append(f"srcflags = {' '.join(src_other + include_flags)}")
+    src_cxx_override = pch_edges(
+        lines,
+        build_dir,
+        src_dir,
+        (*src_includes, *PCH_DEFAULT_HEADERS),
+        flag_sets.cxxflags,
+        src_other,
+        (str(paths.framework), str(paths.toolchain)),
+        cxx,
+    )
+    src_objs = compile_edges(
+        lines,
+        collect_sources(src_dir),
+        src_dir,
+        "src",
+        flags="$srcflags",
+        cxx_override=src_cxx_override,
    )

    ld_deps = [f"ld/{_COMMON_LD_NAME}"]
@@ -1260,3 +1189,28 @@ def _flash_size_str(flash_size: int) -> str:
    """Flash size argument for elf2bin (e.g. ``4M``, ``512K``)."""
    mb = 1024 * 1024
    return f"{flash_size // mb}M" if flash_size >= mb else f"{flash_size // 1024}K"
+
+
+# Same pattern PlatformIO's _get_flash_size applies to the ldscript path
+_LD_FLASH_SIZE_RE = re.compile(r"\.flash\.(\d+[mk]).*\.ld")
+# The framework elf2bin.py's --flash_size choices
+_ELF2BIN_FLASH_SIZES = frozenset({"256K", "512K", "1M", "2M", "4M", "8M", "16M"})
+
+
+def _elf2bin_flash_size(board: str, flash_ld_name: str) -> str:
+    """Image-header flash size as PlatformIO derives it: ldscript filename,
+    else board_upload.maximum_size, else the board table. The SDK clamps the
+    chip to the header size at boot, so a header smaller than the linked
+    layout breaks OTA writes on the running device."""
+    if match := _LD_FLASH_SIZE_RE.search(flash_ld_name):
+        token = match.group(1)
+        base = 1024 if token[-1] == "k" else 1024 * 1024
+        return _flash_size_str(int(token[:-1]) * base)
+    if max_size := _pio_option("board_upload.maximum_size", ""):
+        if (
+            not max_size.isdigit()
+            or (size := _flash_size_str(int(max_size))) not in _ELF2BIN_FLASH_SIZES
+        ):
+            raise EsphomeError(f"Invalid board_upload.maximum_size value {max_size!r}")
+        return size
+    return _flash_size_str(BOARDS[board][KEY_FLASH_SIZE])
@@ -3,7 +3,10 @@
 import json
 import logging
 from pathlib import Path
+import re
+import textwrap

+from esphome.build_helpers import pch
 from esphome.components.esp32 import (
    get_esp32_variant,
    get_excluded_builtin_components,
@@ -18,7 +21,7 @@ from esphome.framework_helpers import (
    get_project_cxx_compile_flags,
    get_project_link_flags,
 )
-from esphome.helpers import mkdir_p, write_file_if_changed
+from esphome.helpers import get_bool_env, mkdir_p, write_file_if_changed

 _LOGGER = logging.getLogger(__name__)

@@ -33,6 +36,83 @@ list(FILTER esphome_cxx_compile_options EXCLUDE REGEX "^-std=")
 list(APPEND esphome_cxx_compile_options "-std={standard}")
 idf_build_set_property(CXX_COMPILE_OPTIONS "${{esphome_cxx_compile_options}}")"""

+# Drops the app archive from ldgen's inputs so app-only edits skip the
+# sections.ld regeneration. Safe: no mapping fragment references it
+# (run_compile re-checks each build). Filters only the top-level call;
+# the prior definition stays reachable with an underscore prefix.
+_LDGEN_OVERRIDE = """\
+if(COMMAND __ldgen_get_lib_deps_of_target)
+    set_property(GLOBAL PROPERTY ESPHOME_LDGEN_ARMED 1)
+    function(__ldgen_get_lib_deps_of_target target out_list_var)
+        if(NOT COMMAND ___ldgen_get_lib_deps_of_target)
+            message(FATAL_ERROR "ESPHome ldgen override lost the original "
+                "implementation; set ESPHOME_LDGEN_FULL_DEPS=1 and rebuild.")
+        endif()
+        ___ldgen_get_lib_deps_of_target(${target} ${out_list_var})
+        if(out_list_var STREQUAL "ldgen_libraries")
+            set_property(GLOBAL PROPERTY ESPHOME_LDGEN_FILTERED 1)
+            list(LENGTH ${out_list_var} esphome_ldgen_before)
+            list(REMOVE_ITEM ${out_list_var} idf::src __idf_src)
+            list(LENGTH ${out_list_var} esphome_ldgen_after)
+            if(esphome_ldgen_before EQUAL esphome_ldgen_after)
+                message(@SEVERITY@ "ESPHome ldgen app archive exclusion matched "
+                    "nothing; app edits will regenerate sections.ld.")
+            endif()
+        endif()
+        set(${out_list_var} "${${out_list_var}}" PARENT_SCOPE)
+    endfunction()
+else()
+    message(@MISSING@ "ESPHome ldgen override target not found; "
+        "app edits will regenerate sections.ld.")
+endif()"""
+
+# lwip sources that compile to empty objects with the option off (their own
+# #if guard). (option, regex valid for both Python and CMake); a source is
+# only dropped when its option is defined and off, so a renamed option
+# keeps it.
+LWIP_EMPTY_SOURCES: tuple[tuple[str, str], ...] = (
+    ("CONFIG_LWIP_PPP_SUPPORT", "/netif/ppp/"),
+    ("CONFIG_LWIP_IPV6", "/core/ipv6/"),
+    ("CONFIG_LWIP_AUTOIP", "/core/ipv4/autoip[.]c$"),
+    ("CONFIG_LWIP_STATS", "/core/stats[.]c$"),
+)
+# Drift guard only: keep every lwip source.
+LWIP_FULL_SOURCES_ENV = "ESPHOME_LWIP_FULL_SOURCES"
+
+# Drops the empty objects after project(), once the lwip target exists.
+_LWIP_EMPTY_SOURCES_FILTER = f"""\
+idf_build_get_property(esphome_build_components BUILD_COMPONENTS)
+if(lwip IN_LIST esphome_build_components AND NOT DEFINED ENV{{{LWIP_FULL_SOURCES_ENV}}})
+    idf_component_get_property(esphome_lwip_lib lwip COMPONENT_LIB)
+    get_target_property(esphome_lwip_srcs ${{esphome_lwip_lib}} SOURCES)
+@FILTERS@
+    set_property(TARGET ${{esphome_lwip_lib}} PROPERTY SOURCES ${{esphome_lwip_srcs}})
+endif()"""
+
+
+def lwip_empty_source_gate(option: str, regex: str) -> str:
+    return (
+        f"    if(DEFINED {option} AND NOT {option})\n"
+        f'        list(FILTER esphome_lwip_srcs EXCLUDE REGEX "{regex}")\n'
+        "    endif()"
+    )
+
+
+def _lwip_empty_sources_filter() -> str:
+    gates = "\n".join(lwip_empty_source_gate(*entry) for entry in LWIP_EMPTY_SOURCES)
+    return _LWIP_EMPTY_SOURCES_FILTER.replace("@FILTERS@", gates)
+
+
+# Runs after project() so the walk has happened; catches the remaining
+# silent path where the top-level out-var was renamed.
+_LDGEN_OVERRIDE_CHECK = """\
+get_property(esphome_ldgen_armed GLOBAL PROPERTY ESPHOME_LDGEN_ARMED)
+get_property(esphome_ldgen_filtered GLOBAL PROPERTY ESPHOME_LDGEN_FILTERED)
+if(esphome_ldgen_armed AND NOT esphome_ldgen_filtered)
+    message(@SEVERITY@ "ESPHome ldgen override never filtered the app "
+        "archive; app edits will regenerate sections.ld.")
+endif()"""
+

 def get_available_components() -> list[str] | None:
    """List the built-in ESP-IDF components from ``project_description.json``.
@@ -78,6 +158,78 @@ def _cmake_quote(value: str) -> str:
    return f'"{escaped}"'


+# CONFIG_APP_BUILD_BOOTLOADER is hidden and force-selected, so it can only be
+# cleared at the CMake level (the same state IDF's RAM-app build type uses).
+# The macro is IDF's __build_process_project_includes plus two added lines;
+# the flag is ignored and the bootloader builds as usual if IDF changes it.
+IDF_BOOTLOADER_OVERRIDE = """\
+# ESPHome bootloader skip switch; see esphome/espidf/toolchain.py.
+if(ESPHOME_SKIP_BOOTLOADER)
+    macro(__build_process_project_includes)
+        idf_build_get_property(sdkconfig_cmake SDKCONFIG_CMAKE)
+        include(${sdkconfig_cmake})
+        set(CONFIG_APP_BUILD_BOOTLOADER "")
+        # bt's CMakeLists reads the lowercase idf_target that the (now
+        # skipped) bootloader project_include leaks; keep it defined, or
+        # its empty TARGET_SRC_NAME sends file(GLOB_RECURSE) across /.
+        idf_build_get_property(idf_target IDF_TARGET)
+        idf_build_get_property(build_properties __BUILD_PROPERTIES)
+        foreach(build_property ${build_properties})
+            idf_build_get_property(val ${build_property})
+            set(${build_property} "${val}")
+        endforeach()
+        idf_build_get_property(build_component_targets __BUILD_COMPONENT_TARGETS)
+        foreach(component_target ${build_component_targets})
+            __component_get_property(dir ${component_target} COMPONENT_DIR)
+            __component_get_property(_name ${component_target} COMPONENT_NAME)
+            set(COMPONENT_NAME ${_name})
+            set(COMPONENT_DIR ${dir})
+            set(COMPONENT_PATH ${dir})
+            if(EXISTS ${COMPONENT_DIR}/project_include.cmake)
+                include(${COMPONENT_DIR}/project_include.cmake)
+            endif()
+        endforeach()
+    endmacro()
+endif()
+"""
+
+# The lines the override adds to IDF's macro; idf_macro_matches() below
+# strips them before comparing with the live macro.
+BOOTLOADER_OVERRIDE_ADDED_LINES = (
+    'set(CONFIG_APP_BUILD_BOOTLOADER "")',
+    "idf_build_get_property(idf_target IDF_TARGET)",
+)
+
+_MACRO = re.compile(
+    r"macro\(__build_process_project_includes\)(.*?)endmacro\(\)", re.DOTALL
+)
+
+
+def _normalized_macro(text: str) -> list[str] | None:
+    """The macro body as comment-free, whitespace-collapsed lines."""
+    if (match := _MACRO.search(text)) is None:
+        return None
+    return [
+        re.sub(r"\s+", " ", line)
+        for raw in match.group(1).splitlines()
+        if (line := raw.split("#", 1)[0].strip())
+    ]
+
+
+_EXPECTED_MACRO = [
+    line
+    for line in _normalized_macro(IDF_BOOTLOADER_OVERRIDE)
+    if line not in BOOTLOADER_OVERRIDE_ADDED_LINES
+]
+
+
+def idf_macro_matches(idf_path: Path) -> bool:
+    """Whether IDF's macro still matches the copy the override replays."""
+    build_cmake = idf_path / "tools" / "cmake" / "build.cmake"
+    live = _normalized_macro(build_cmake.read_text(encoding="utf-8"))
+    return live == _EXPECTED_MACRO
+
+
 def get_project_cmakelists(
    minimal: bool = False, builtin_components: list[str] | None = None
 ) -> str:
@@ -123,6 +275,22 @@ def get_project_cmakelists(
        else ""
    )

+    # Stops the ~3s sections.ld regeneration on app-only edits; see
+    # _LDGEN_OVERRIDE. ESPHOME_LDGEN_FULL_DEPS=1 restores stock behavior;
+    # ESPHOME_LDGEN_STRICT=1 (CI) fails the configure when an IDF bump
+    # breaks the override instead of degrading to stock deps.
+    if get_bool_env("ESPHOME_LDGEN_FULL_DEPS"):
+        ldgen_override = ""
+        ldgen_override_check = ""
+    else:
+        strict = get_bool_env("ESPHOME_LDGEN_STRICT")
+        severity = "FATAL_ERROR" if strict else "WARNING"
+        missing = "FATAL_ERROR" if strict else "STATUS"
+        ldgen_override = _LDGEN_OVERRIDE.replace("@SEVERITY@", severity).replace(
+            "@MISSING@", missing
+        )
+        ldgen_override_check = _LDGEN_OVERRIDE_CHECK.replace("@SEVERITY@", severity)
+
    # CMake variables registered via cg.add_cmake_arg(). Emitted before
    # include(project.cmake) so values like EXCLUDE_COMPONENTS are already
    # set when project.cmake seeds the component list, and on minimal
@@ -200,6 +368,9 @@ set(EXTRA_COMPONENT_DIRS ${{CMAKE_SOURCE_DIR}}/src)

 include($ENV{{IDF_PATH}}/tools/cmake/project.cmake)

+{IDF_BOOTLOADER_OVERRIDE}
+{ldgen_override}
+
 {cpp_standard_options}

 {cxx_compile_options}
@@ -212,14 +383,22 @@ include($ENV{{IDF_PATH}}/tools/cmake/project.cmake)

 project({CORE.name})

+{ldgen_override_check}
+
+{_lwip_empty_sources_filter()}
+
 # Emit per-memory-type JSON size data for ESPHome to read post-build.
 # json2 stays small; raw dumps every symbol (~2s on a large map) and
 # this command runs inside the link edge, blocking everything downstream.
+# The map is a BYPRODUCT so ninja knows the link writes it; IDF's size
+# target depends on the map and can then be built in the same run as all.
+# IDF's cmakev2 declares the map itself, so drop this line on that switch.
 add_custom_command(
    TARGET ${{CMAKE_PROJECT_NAME}}.elf POST_BUILD
    COMMAND ${{PYTHON}} -m esp_idf_size {size_ng_flag} --format=json2
            -o ${{CMAKE_BINARY_DIR}}/esp_idf_size.json
            ${{CMAKE_PROJECT_NAME}}.map
+    BYPRODUCTS ${{CMAKE_BINARY_DIR}}/${{CMAKE_PROJECT_NAME}}.map
    WORKING_DIRECTORY ${{CMAKE_BINARY_DIR}}
    VERBATIM
 )
@@ -282,9 +461,72 @@ idf_component_register(
 target_link_options(${{COMPONENT_LIB}} PUBLIC
    {link_opts_str}
 )
+{_pch_cmake_block()}"""
+
+
+# Where CMake puts the .gch of the src component; ccache reads the checksum
+# next to it in place of the .gch
+_PCH_SUM_PATH = "build/esp-idf/src/CMakeFiles/__idf_src.dir/cmake_pch.hxx.gch.sum"
+# Where the Windows gate records its choice
+_PCH_CHOICE_VAR = "ESPHOME_PCH"
+
+
+def _pch_cmake_block() -> str:
+    """The CMake block that precompiles the core headers for the C++ sources
+    of the src component; empty when disabled."""
+    if not pch.pch_enabled():
+        return ""
+    headers = "\n".join(
+        f'    "$<$<COMPILE_LANGUAGE:CXX>:${{CMAKE_CURRENT_SOURCE_DIR}}/{header}>"'
+        for header in pch.PCH_DEFAULT_HEADERS
+    )
+    block = f"""target_precompile_headers(${{COMPONENT_LIB}} PRIVATE
+{headers}
+)"""
+    if not pch.pch_needs_gcc_check():
+        return f"\n# ESPHome precompiled header\n{block}\n"
+    # Before the first configure only CMake knows the compiler version
+    return f"""
+# ESPHome precompiled header, unless GCC bug 14940 keeps it from loading
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND ({pch.PCH_WINDOWS_CMAKE_OLD_GCC}))
+  message(STATUS "ESPHome: GCC ${{CMAKE_CXX_COMPILER_VERSION}} cannot load a precompiled header on Windows; compiling without it")
+  set({_PCH_CHOICE_VAR} OFF CACHE BOOL "ESPHome precompiled header in use" FORCE)
+else()
+  set({_PCH_CHOICE_VAR} ON CACHE BOOL "ESPHome precompiled header in use" FORCE)
+{textwrap.indent(block, "  ")}
+endif()
 """


+def _read_if_exists(path: Path) -> str:
+    return path.read_text(encoding="utf-8") if path.is_file() else ""
+
+
+def write_pch_checksum() -> None:
+    """Write the checksum ccache uses in place of the .gch: the core headers,
+    the framework version, the sdkconfig and the managed component versions."""
+    from esphome.espidf.toolchain import get_cmake_cache_value
+
+    if not pch.pch_enabled():
+        return
+    # The gate's choice, cached by configure
+    if pch.pch_needs_gcc_check() and get_cmake_cache_value(_PCH_CHOICE_VAR) != "ON":
+        return
+    pch.log_pch_in_use()
+    checksum = pch.pch_checksum(
+        CORE.relative_src_path(),
+        pch.PCH_DEFAULT_HEADERS,
+        (
+            str(idf_version()),
+            _read_if_exists(CORE.relative_build_path(f"sdkconfig.{CORE.name}")),
+            _read_if_exists(CORE.relative_build_path("dependencies.lock")),
+        ),
+    )
+    path = CORE.relative_build_path(_PCH_SUM_PATH)
+    path.parent.mkdir(parents=True, exist_ok=True)
+    write_file_if_changed(path, checksum + "\n")
+
+
 def write_project(
    minimal: bool = False, builtin_components: list[str] | None = None
 ) -> None:
@@ -0,0 +1,303 @@
+"""Native ninja build generator for the host platform.
+
+Emits ``build.ninja`` under ``.pioenvs/<name>/``: every source in the
+generated ``src/`` tree plus the resolved registry libraries compiles with
+the machine's compiler and links into ``program``, the name PlatformIO's
+native platform produced. Build flags route the way SCons's ``ParseFlags``
+did under PlatformIO: ``-D``/``-I``/``-std=``/``-W`` shapes reach the
+compile lines only, ``-l``/``-L``/``-Wl,`` the link line only, everything
+else both.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Iterable
+import logging
+import os
+from pathlib import Path
+import subprocess
+import sys
+from typing import TYPE_CHECKING
+
+from esphome.build_helpers.ninja import escape as _e, quote_path as _q, shell_token
+from esphome.build_helpers.ninja_gen import (
+    PATH_ARG_FLAGS,
+    Flag,
+    anchor_path_flag,
+    ar_rule_lines,
+    collect_sources,
+    compile_edges,
+    compile_rule_lines,
+    library_edges,
+    pch_edges,
+    pch_rule_lines,
+    tool_lines,
+)
+from esphome.build_helpers.pch import PCH_DEFAULT_HEADERS, pch_enabled
+from esphome.core import CORE, EsphomeError
+from esphome.framework_helpers import get_project_cxx_compile_flags
+from esphome.helpers import mkdir_p, write_file_if_changed
+from esphome.host.toolchain import PROGRAM_NAME, HostCompilers, find_tool, get_build_dir
+from esphome.platformio.library import lex_build_flags
+
+if TYPE_CHECKING:
+    from esphome.arduino.library import ArduinoLibrary
+
+_LOGGER = logging.getLogger(__name__)
+
+# The PlatformIO platform the host built under; registry manifests declare
+# compatibility against it, as lib_compat_mode=strict checked before
+PIO_PLATFORM = "native"
+# Namespaces the shared library download cache (pio_components/host/)
+LIBRARY_CACHE_KEY = "host"
+
+# Flag shapes that only the compiler understands; dropped from the link line
+_COMPILE_ONLY_PREFIXES = ("-D", "-U", "-I", "-std=", "-W", *PATH_ARG_FLAGS)
+# Flag shapes that only the linker consumes; inert on a -c compile line
+_LINK_ONLY_PREFIXES = ("-l", "-L", "-Wl,")
+# Link-only flags whose argument is the next token
+_LINK_ONLY_ARG_FLAGS = ("-framework", "-Xlinker", "-z")
+
+
+def parse_flags(entries: Iterable[str], owner: str) -> list[Flag]:
+    """Lex build flag entries into flags, each with its argument.
+
+    Entries are a set, so their order is not the user's: a flag and the
+    argument it takes as the next token must share one entry.
+    """
+    flags: list[Flag] = []
+    for entry in entries:
+        it = iter(lex_build_flags(entry, owner))
+        for tok in it:
+            if tok not in PATH_ARG_FLAGS and tok not in _LINK_ONLY_ARG_FLAGS:
+                flags.append((tok,))
+                continue
+            arg = next(it, None)
+            # A path never starts with "-"; that is the next flag
+            if arg is None or (tok in PATH_ARG_FLAGS and arg.startswith("-")):
+                raise EsphomeError(
+                    f"{owner} build flags have '{tok}' with no argument; write "
+                    f"the flag and its argument as one entry"
+                )
+            flags.append((tok, arg))
+    return flags
+
+
+def split_flags(flags: list[Flag]) -> tuple[list[Flag], list[Flag]]:
+    """Route build flags to the compile and link lines."""
+    compile_flags: list[Flag] = []
+    link_flags: list[Flag] = []
+    for flag in flags:
+        name = flag[0]
+        if len(flag) > 1:
+            (compile_flags if name in PATH_ARG_FLAGS else link_flags).append(flag)
+        elif name.startswith(_LINK_ONLY_PREFIXES):
+            # Checked before the compile prefixes: -Wl, would match -W
+            link_flags.append(flag)
+        elif name.startswith(_COMPILE_ONLY_PREFIXES):
+            compile_flags.append(flag)
+        else:
+            # -g, -O, -f*, -m*, -pthread, --coverage: both lines, as SCons
+            compile_flags.append(flag)
+            link_flags.append(flag)
+    return compile_flags, link_flags
+
+
+def _is_std(flag: Flag) -> bool:
+    return flag[0].startswith("-std=")
+
+
+def _is_cxx_std(flag: Flag) -> bool:
+    return _is_std(flag) and "++" in flag[0]
+
+
+def _anchored_flags(entries: Iterable[str], owner: str) -> list[Flag]:
+    build_path = Path(CORE.build_path)
+    return [
+        anchor_path_flag(flag, build_path)
+        for flag in parse_flags(sorted(entries), owner)
+    ]
+
+
+def _flag_lists() -> tuple[list[str], list[str], list[str]]:
+    """The C, C++, and link flag lists (raw tokens), build_unflags applied.
+
+    ``cg.set_cpp_standard`` wins over any ``-std=`` in the build flags for
+    C++ compiles, as PlatformIO's unflag of every other standard did; C
+    compiles never see a C++ standard.
+    """
+    # The funnel warns and drops empty glued arguments (-D "") itself
+    compile_flags, link_flags = split_flags(
+        _anchored_flags(CORE.build_flags, "esphome")
+    )
+    cflags = [f for f in compile_flags if not _is_cxx_std(f)]
+    cxx_std = CORE.cpp_standard
+    cxxflags = [f for f in compile_flags if not (cxx_std and _is_std(f))]
+    if cxx_std:
+        cxxflags.insert(0, (f"-std={cxx_std}",))
+    cxxflags += [(tok,) for tok in get_project_cxx_compile_flags()]
+
+    # A flag is removed whole, with its argument, as PlatformIO did
+    unflags = set(_anchored_flags(CORE.build_unflags, "esphome build_unflags"))
+    # An unflag that hits nothing (a typo, or -DUSE_FOO against
+    # -DUSE_FOO=1) must be visible, since the user believes the flag is
+    # gone while it still drives the build
+    if unmatched := sorted(unflags - set(cflags) - set(cxxflags) - set(link_flags)):
+        _LOGGER.warning(
+            "build_unflags entries matched no build flag: %s",
+            ", ".join(" ".join(flag) for flag in unmatched),
+        )
+
+    def keep(flags: list[Flag]) -> list[str]:
+        return [tok for flag in flags if flag not in unflags for tok in flag]
+
+    return keep(cflags), keep(cxxflags), keep(link_flags)
+
+
+def _resolve_host_libraries() -> list[ArduinoLibrary]:
+    """Every ``cg.add_library()`` entry, fetched from the registry.
+
+    The host has no framework, so nothing is bundled and no framework
+    compatibility check applies; the platform check keeps the strict
+    manifest gate PlatformIO's native platform enforced. Manifest-less
+    libraries (a bare git checkout) build with PlatformIO's default
+    layout, as they did under its native platform.
+    """
+    if not CORE.platformio_libraries:
+        return []
+    from esphome.arduino.library import resolve_libraries
+
+    return resolve_libraries(
+        None,
+        pio_platform=PIO_PLATFORM,
+        board_mcu="host",
+        cache_key=LIBRARY_CACHE_KEY,
+        framework=None,
+        manifest_optional=True,
+    )
+
+
+def _file_macro_maps(build_dir: Path) -> list[str]:
+    """Flags that keep ``__FILE__`` relative to the build path.
+
+    PlatformIO compiled ``src/x.cpp`` from the build path, and tools name
+    things after that spelling (CodSpeed's benchmark ids). Here a source
+    reaches the compiler by its absolute path, or relative to the build
+    directory when ccache rewrites it.
+    """
+    build_path = Path(CORE.build_path)
+    prefixes = (build_path, Path(os.path.relpath(build_path, build_dir)))
+    return [
+        shell_token(f"-fmacro-prefix-map={prefix}{os.sep}=", force=True)
+        for prefix in prefixes
+    ]
+
+
+def _compiler_version(cxx: tuple[str, ...]) -> str:
+    """What the compiler says it is: its path can stay the same across an
+    update (the macOS shims in /usr/bin)."""
+    result = subprocess.run(
+        [*cxx, "--version"], capture_output=True, text=True, check=False
+    )
+    return result.stdout
+
+
+def write_project(compilers: HostCompilers, ccache: str | None) -> bool:
+    """Write the ninja build for the current configuration.
+
+    ``ccache`` is the caller's already-resolved binary (None when disabled).
+    Returns True when ``build.ninja`` changed, so the caller can skip work
+    derived purely from it (the compile database) on unchanged builds.
+    """
+    build_dir = get_build_dir()
+    mkdir_p(build_dir)
+    src_dir = CORE.relative_src_path()
+    if not src_dir.is_dir():
+        # Generated project state, not install state: clean-all would not help
+        raise EsphomeError(f"Generated source directory {src_dir} is missing")
+
+    cflags, cxxflags, link_flags = _flag_lists()
+    libraries = _resolve_host_libraries()
+
+    include_dirs = [src_dir]
+    for lib in libraries:
+        include_dirs += lib.include_dirs
+    includes = [f"-I{_q(d)}" for d in include_dirs]
+    includes += _file_macro_maps(build_dir)
+
+    # SCons's link line: $LINKFLAGS $SOURCES $_LIBDIRFLAGS $_LIBFLAGS, so
+    # -L and -l trail the objects while every other link token leads
+    lib_dirs = [Path(t[2:]) for t in link_flags if t.startswith("-L")]
+    libs = [t for t in link_flags if t.startswith("-l")]
+    linkflags = [shell_token(t) for t in link_flags if not t.startswith(("-L", "-l"))]
+    for lib in libraries:
+        lib_dirs += lib.link_dirs
+        libs += [f"-l{name}" for name in lib.link_libs]
+        linkflags += [shell_token(f) for f in lib.link_flags]
+
+    # PlatformIO's ASPPCOM passes only -D/-I user flags to assembly
+    asflags = [t for t in cflags if t.startswith(("-D", "-I"))]
+
+    lines = [
+        *tool_lines(compilers.cc, compilers.cxx, ccache),
+        *compile_rule_lines(),
+        *pch_rule_lines(),
+        "rule link",
+        "  command = $cxx -o $out $linkflags @$out.rsp $archives $libdirflags $libflags",
+        "  rspfile = $out.rsp",
+        "  rspfile_content = $in_newline",
+        "  description = LINK $out",
+    ]
+    if any(lib.sources and lib.lib_archive for lib in libraries):
+        # Resolved only when an archive is built, so a system without
+        # binutils still links a library-free configuration
+        lines += ar_rule_lines(find_tool("AR", ("ar",)))
+    lines += [
+        "",
+        f"cflags = {' '.join([*map(shell_token, cflags), *includes])}",
+        f"cxxflags = {' '.join([*map(shell_token, cxxflags), *includes])}",
+        f"asflags = {' '.join([*map(shell_token, asflags), *includes])}",
+        f"linkflags = {' '.join(linkflags)}",
+        f"libdirflags = {' '.join(f'-L{_q(d)}' for d in lib_dirs)}",
+        f"libflags = {' '.join(shell_token(lib) for lib in libs)}",
+        "",
+    ]
+
+    archives, direct_objs = library_edges(lines, libraries)
+
+    src_cxx_override = pch_edges(
+        lines,
+        build_dir,
+        src_dir,
+        PCH_DEFAULT_HEADERS,
+        # The arguments of a CXX override come before the flags
+        [*compilers.cxx[1:], *cxxflags],
+        (),
+        (compilers.cxx[0], _compiler_version(compilers.cxx)) if pch_enabled() else (),
+        compilers.cxx,
+    )
+    src_objs = compile_edges(
+        lines,
+        collect_sources(src_dir),
+        src_dir,
+        "src",
+        cxx_override=src_cxx_override,
+    )
+    if not src_objs:
+        raise EsphomeError(f"No source files found under {src_dir}")
+
+    # Archives are not topologically sorted; GNU ld needs the group to
+    # resolve references between them. ld64 loads archives iteratively and
+    # rejects the option, so macOS lists them bare.
+    archive_tokens = [shell_token(a) for a in archives]
+    if archive_tokens and sys.platform != "darwin":
+        archive_tokens = ["-Wl,--start-group", *archive_tokens, "-Wl,--end-group"]
+    lines.append(
+        f"build {PROGRAM_NAME}: link {' '.join(src_objs + direct_objs)} | "
+        f"{' '.join(_e(a) for a in archives)}"
+    )
+    lines.append(f"  archives = {' '.join(archive_tokens)}")
+    lines.append(f"default {PROGRAM_NAME}")
+    lines.append("")
+
+    return write_file_if_changed(build_dir / "build.ninja", "\n".join(lines))
@@ -1,6 +1,8 @@
+from esphome.build_helpers.pch import pch_script_enabled
 from esphome.const import __version__
 from esphome.core import CORE
 from esphome.helpers import mkdir_p, read_file, write_file_if_changed
+from esphome.platformio.toolchain import copy_pch_script
 from esphome.writer import find_begin_end

 INI_AUTO_GENERATE_BEGIN = "; ========== AUTO GENERATED CODE BEGIN ==========="
@@ -62,6 +64,8 @@ def get_ini_content():

    # Add extra script for C++ flags
    CORE.add_platformio_option("extra_scripts", [f"pre:{CXX_FLAGS_FILE_NAME}"])
+    if pch_script_enabled():
+        CORE.add_platformio_option("extra_scripts", ["post:pch.py"])

    # Add CMake args. A user-supplied value (str or list) is deliberately
    # replaced; this option was always overwritten at FINAL priority.
@@ -106,6 +110,8 @@ def write_project():

    # Write extra script for C++ specific flags
    write_cxx_flags_script()
+    if pch_script_enabled():
+        copy_pch_script()


 CXX_FLAGS_FILE_NAME = "cxx_flags.py"
@@ -68,6 +68,15 @@ def resolve_ccache_path() -> str | None:
    return ccache


+def resolve_absolute_ccache_path() -> str | None:
+    """``resolve_ccache_path`` for the ninja backends, which run their
+    commands from the build directory, where a relative path is lost."""
+    from esphome.build_helpers.ninja import absolute_tool
+
+    ccache = resolve_ccache_path()
+    return absolute_tool(ccache) if ccache else None
+
+
 def ccache_defaults_env(cache_dir: Path) -> dict[str, str]:
    """Default ``CCACHE_*`` values for a build subprocess (not os.environ).

@@ -84,9 +93,39 @@ def ccache_defaults_env(cache_dir: Path) -> dict[str, str]:
            "CORE.build_path must be set before constructing the build environment"
        )
    defaults = {
-        "CCACHE_DIR": str(cache_dir),
+        # ccache expands $VAR in its settings; $$ is a literal $
+        "CCACHE_DIR": str(cache_dir).replace("$", "$$"),
        "CCACHE_NOHASHDIR": "true",
        "CCACHE_DEPEND": "1",
-        "CCACHE_BASEDIR": str(Path(CORE.build_path).resolve()),
+        "CCACHE_BASEDIR": str(Path(CORE.build_path).resolve()).replace("$", "$$"),
    }
    return {k: v for k, v in defaults.items() if k not in os.environ}
+
+
+def effective_ccache_basedir() -> str:
+    """The prefix ccache strips from hashed paths: a usable user
+    CCACHE_BASEDIR, else the resolved build path."""
+    from esphome.core import CORE
+
+    raw = os.environ.get("CCACHE_BASEDIR")
+    if raw is not None and Path(raw).is_absolute() and len(Path(raw).parts) > 1:
+        return raw
+    return str(Path(CORE.build_path).resolve())
+
+
+def ccache_env(ccache: str | None, tools_cache: tuple[str, str]) -> dict[str, str]:
+    """The ccache settings for a build subprocess (not os.environ).
+
+    ``ccache`` is the pre-resolved binary (resolve_ccache_path), or None when
+    disabled; ``tools_cache`` is the backend's tools cache spec, which holds
+    its ccache dir. The pch settings include ``time_macros``: a cached
+    object can keep an older ``__DATE__`` or ``__TIME__``.
+    """
+    if ccache is None:
+        return {}
+    from esphome.build_helpers.pch import ccache_pch_env
+    from esphome.build_helpers.tools_cache import tools_cache_path
+
+    env = ccache_defaults_env(tools_cache_path(*tools_cache) / "ccache")
+    env.update(ccache_pch_env())
+    return env
@@ -152,6 +152,15 @@ def _is_launcher(token: str) -> bool:
    return Path(token).stem.lower() in _LAUNCHER_STEMS


+def is_joined_include(tok: str) -> bool:
+    """The joined ``-includefoo.h`` spelling; excludes clang's -include-pch."""
+    return (
+        tok.startswith("-include")
+        and tok != "-include"
+        and not tok.startswith("-include-")
+    )
+
+
 def parse_entry(
    entry: dict, launcher: str | None = None
 ) -> tuple[str, list[str], list[str], list[str]]:
@@ -7,16 +7,21 @@ platform component package or the backend itself.

 from __future__ import annotations

+from collections.abc import Collection
 import importlib
+import logging
 from types import ModuleType

 from esphome.const import Toolchain
 from esphome.core import CORE, EsphomeError

+_LOGGER = logging.getLogger(__name__)
+
 # Native build backend per (target platform, toolchain)
 NATIVE_TOOLCHAIN_MODULES = {
    ("esp32", Toolchain.ESP_IDF): "esphome.espidf.toolchain",
    ("esp8266", Toolchain.ARDUINO): "esphome.arduino8266.toolchain",
+    ("host", Toolchain.HOST): "esphome.host.toolchain",
 }


@@ -32,3 +37,38 @@ def native_backend() -> ModuleType | None:
            f"module for platform {CORE.target_platform}"
        )
    return importlib.import_module(module_path)
+
+
+# Binutils and the linked image for memory analysis, for toolchains that build
+# without PlatformIO but have no native build backend (which supplies them)
+ANALYSIS_TOOLCHAIN_MODULES = {
+    ("nrf52", Toolchain.SDK_NRF): "esphome.components.nrf52.toolchain",
+}
+
+
+def analysis_backend() -> ModuleType | None:
+    """The module giving objdump, readelf and the ELF of a non-PlatformIO build.
+
+    None means PlatformIO's idedata supplies them (or nothing can).
+    """
+    if (native := native_backend()) is not None:
+        return native
+    module_path = ANALYSIS_TOOLCHAIN_MODULES.get((CORE.target_platform, CORE.toolchain))
+    return importlib.import_module(module_path) if module_path else None
+
+
+def warn_ignored_platformio_options(consumed: Collection[str]) -> None:
+    """Warn for component-added platformio options a native build drops.
+
+    User-supplied keys were already routed or warned about by
+    ``core/config.py``; what survives into ``CORE.platformio_options`` came
+    from ``cg.add_platformio_option`` calls in components.
+    """
+    for key in sorted(CORE.platformio_options or {}):
+        if key not in consumed:
+            _LOGGER.warning(
+                "platformio_options->%s is ignored when building with the "
+                "native '%s' toolchain",
+                key,
+                CORE.toolchain.value,
+            )
@@ -2,14 +2,17 @@

 from __future__ import annotations

+import json
 import logging
 import os
 from pathlib import Path
 import re
 import shutil
+import subprocess

 from esphome.core import EsphomeError
 from esphome.framework_helpers import strip_win_long_path_prefix, tool_version_runs
+from esphome.helpers import write_file_if_changed

 _LOGGER = logging.getLogger(__name__)

@@ -23,11 +26,26 @@ def _ninja_runs(binary: str) -> bool:
    )


+# Compile rule names the generators emit; ninja's compdb tool is asked for
+# exactly these, so a renamed rule fails the build instead of stranding idedata
+COMPILE_RULES = ("c", "cxx", "aspp", "asm")
+
+
+def absolute_tool(tool: str | Path) -> str:
+    """A tool path that still resolves from the build directory.
+
+    ``shutil.which`` returns a relative path for a relative PATH entry, and
+    ninja runs the commands from ``.pioenvs/<name>``. Symlinks are kept:
+    ccache's compiler links depend on the name they are called by.
+    """
+    return strip_win_long_path_prefix(str(Path(tool).absolute()))
+
+
 def find_ninja() -> Path:
    """Locate the ninja binary: a runnable PATH hit first, else the ninja
    PyPI wheel."""
    if binary := shutil.which("ninja"):
-        binary = strip_win_long_path_prefix(binary)
+        binary = absolute_tool(binary)
        if _ninja_runs(binary):
            return Path(binary)
    import_error: ImportError | None = None
@@ -49,8 +67,18 @@ def find_ninja() -> Path:


 def escape(value: Path | str) -> str:
-    """Escape a path or token for a ninja file."""
-    return str(value).replace("$", "$$").replace(":", "$:").replace(" ", "$ ")
+    """Escape a path or token for a ninja file.
+
+    ninja has no escape for ``|`` or a line break in a path, so those fail
+    here by name instead of producing a build file ninja misreads.
+    """
+    text = str(value)
+    if bad := next((c for c in "|\r\n" if c in text), None):
+        raise EsphomeError(
+            f"Path {text!r} contains {bad!r}, which a ninja build file cannot "
+            "express; rename the file or directory"
+        )
+    return text.replace("$", "$$").replace(":", "$:").replace(" ", "$ ")


 def quote_arg(tok: str) -> str:
@@ -90,3 +118,65 @@ def shell_token(tok: str, force: bool = False) -> str:
 def quote_path(value: Path | str) -> str:
    """Force-quote a path for the ninja command line (shell/CreateProcess)."""
    return shell_token(str(value), force=True)
+
+
+def refresh_compile_commands(
+    ninja_path: Path, build_dir: Path, env: dict[str, str], ninja_changed: bool
+) -> None:
+    """Regenerate the compile DB (a pure function of build.ninja) when stale.
+
+    Freshness rides a stamp: the DB itself is written through
+    write_file_if_changed (its mtime feeds the idedata cache), so a
+    regeneration with identical content would stay "stale" forever. An
+    interrupted previous run may have rewritten the manifest without
+    regenerating the DB, hence the mtime comparison.
+    """
+    compdb = build_dir / "compile_commands.json"
+    compdb_stamp = build_dir / ".compile_commands.stamp"
+    ninja_file = build_dir / "build.ninja"
+    if (
+        ninja_changed
+        or not compdb.is_file()
+        or not compdb_stamp.is_file()
+        or compdb_stamp.stat().st_mtime < ninja_file.stat().st_mtime
+    ):
+        write_compile_commands(ninja_path, build_dir, env)
+        compdb_stamp.touch()
+
+
+def write_compile_commands(
+    ninja_path: Path, build_dir: Path, env: dict[str, str]
+) -> None:
+    compdb = build_dir / "compile_commands.json"
+    result = subprocess.run(
+        [str(ninja_path), "-C", str(build_dir), "-t", "compdb", *COMPILE_RULES],
+        env=env,
+        capture_output=True,
+        text=True,
+        check=False,
+        close_fds=False,
+    )
+    if result.returncode != 0:
+        # Drop any stale database so consumers (IDE integration, clang-tidy,
+        # the memory analyzer) can't silently read outdated data
+        compdb.unlink(missing_ok=True)
+        raise EsphomeError(f"Could not generate compile_commands.json: {result.stderr}")
+    try:
+        entries = json.loads(result.stdout)
+    except ValueError as err:
+        compdb.unlink(missing_ok=True)
+        raise EsphomeError(
+            f"ninja produced an unparsable compile database: {err} "
+            f"(output starts {result.stdout[:120]!r})"
+        ) from err
+    if not entries:
+        # compdb exits 0 with [] for unknown rule names; a renamed compile
+        # rule must fail the build, not silently strand every consumer
+        compdb.unlink(missing_ok=True)
+        raise EsphomeError(
+            "ninja produced an empty compile database; the generator's rule "
+            "names no longer match"
+        )
+    # write_file_if_changed keeps the mtime stable on no-op builds so the
+    # idedata cache stays valid
+    write_file_if_changed(compdb, result.stdout)
@@ -0,0 +1,279 @@
+"""The parts of a ``build.ninja`` every native backend emits the same way.
+
+Rule names match ``SOURCE_KIND_FOR_SUFFIX`` values (c, cxx, asm, aspp) and
+``ninja.COMPILE_RULES``, which the compile database is asked for.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Collection, Sequence
+import logging
+import os
+from pathlib import Path
+import sys
+from typing import TYPE_CHECKING
+
+from esphome.build_helpers.idedata import is_joined_include
+from esphome.build_helpers.ninja import (
+    escape as _e,
+    quote_path as _q,
+    shell_token as _shell_token,
+)
+from esphome.build_helpers.pch import (
+    PCH_GCH_NAME,
+    PCH_SUM_NAME,
+    log_pch_in_use,
+    pch_consumer_flags,
+    pch_identity,
+    pch_usable,
+    write_pch_headers,
+)
+from esphome.framework_helpers import strip_win_long_path_prefix
+from esphome.helpers import write_file_if_changed
+from esphome.platformio.library import SOURCE_KIND_FOR_SUFFIX
+
+if TYPE_CHECKING:
+    from esphome.arduino.library import ArduinoLibrary
+
+_LOGGER = logging.getLogger(__name__)
+
+_BUILD_TOOL = Path(__file__).parent.parent / "build_gen" / "build_tool.py"
+
+
+def collect_sources(root: Path, exclude: Collection[str] = frozenset()) -> list[Path]:
+    return sorted(
+        p
+        for p in root.rglob("*")
+        if p.suffix in SOURCE_KIND_FOR_SUFFIX and p.name not in exclude
+    )
+
+
+def common_parent(paths: list[Path]) -> Path:
+    return Path(os.path.commonpath([str(p.parent) for p in paths]))
+
+
+def _command(words: Sequence[Path | str]) -> str:
+    program, *args = words
+    return " ".join([_q(program), *(_shell_token(str(a)) for a in args)])
+
+
+def tool_lines(
+    cc: Sequence[Path | str], cxx: Sequence[Path | str], ccache: str | None
+) -> list[str]:
+    """The file header: the compilers and the helper tools as variables.
+
+    A compiler is its program followed by any arguments it always takes.
+    """
+    return [
+        "# Auto-generated by ESPHome",
+        "ninja_required_version = 1.5",
+        f"cc = {_command(cc)}",
+        f"cxx = {_command(cxx)}",
+        # The NSIS launcher starts Python with a \\?\ extended-length path
+        # that cmd.exe cannot spawn; same strip every other emitted binary
+        # path gets
+        f"python = {_q(strip_win_long_path_prefix(sys.executable))}",
+        f"buildtool = {_q(_BUILD_TOOL)}",
+        f"ccache = {_q(ccache) if ccache else ''}",
+        "",
+    ]
+
+
+def compile_rule_lines() -> list[str]:
+    """The compile rules; ``$own_includes`` is empty unless an edge sets it."""
+    return [
+        "rule c",
+        "  command = $ccache $cc -MMD -MF $out.d $own_includes $cflags $flags -c $in -o $out",
+        "  depfile = $out.d",
+        "  deps = gcc",
+        "  description = CC $out",
+        "rule cxx",
+        "  command = $ccache $cxx -MMD -MF $out.d $own_includes $cxxflags $flags -c $in -o $out",
+        "  depfile = $out.d",
+        "  deps = gcc",
+        "  description = CXX $out",
+        "rule aspp",
+        "  command = $ccache $cc -MMD -MF $out.d -x assembler-with-cpp $own_includes $asflags $flags -c $in -o $out",
+        "  depfile = $out.d",
+        "  deps = gcc",
+        "  description = AS $out",
+        # Plain assembler, as SCons's ASCOM: no preprocessor, so no
+        # depfile and no $flags (defines/includes) either
+        "rule asm",
+        "  command = $ccache $cc -x assembler $asflags -c $in -o $out",
+        "  description = AS $out",
+    ]
+
+
+def pch_rule_lines() -> list[str]:
+    """The precompiled header rule, for a generator that emits one."""
+    return [
+        # No $ccache: the .gch embeds build dir paths
+        "rule pch",
+        "  command = $cxx -MMD -MF $out.d -x c++-header $cxxflags $flags -c $in -o $out",
+        "  depfile = $out.d",
+        "  deps = gcc",
+        "  description = PCH $out",
+    ]
+
+
+def pch_edges(
+    lines: list[str],
+    build_dir: Path,
+    src_dir: Path,
+    headers: Sequence[str],
+    cxxflags: Sequence[str],
+    src_flags: Sequence[str],
+    identity: Sequence[str],
+    cxx: Sequence[Path | str],
+) -> tuple[str, str] | None:
+    """Emit the precompiled header for the C++ src edges.
+
+    ``headers`` are folded into one prefix header, ``src_flags`` are the
+    flags every src edge carries, ``identity`` names what else the compile
+    depends on, the compiler included, and ``cxx`` is what the host rule
+    asks. Returns the ``cxx_override`` for ``compile_edges``, or None
+    without a pch.
+    """
+    if not pch_usable(cxx):
+        return None
+    if any(
+        tok == "-include" or tok.startswith("--include") or is_joined_include(tok)
+        for tok in cxxflags
+    ):
+        # $cxxflags expands first and GCC only loads a .gch for the first
+        # -include
+        _LOGGER.warning(
+            "A -include in the compiler flags prevents the precompiled header from "
+            "loading; compiling without it"
+        )
+        return None
+    log_pch_in_use()
+    source = write_pch_headers(build_dir, headers)
+    write_file_if_changed(
+        build_dir / PCH_SUM_NAME,
+        pch_identity([*cxxflags, *src_flags], src_dir, tuple(headers), identity) + "\n",
+    )
+    gch = _e(PCH_GCH_NAME)
+    # The checksum file changes with anything the .gch depends on
+    lines.append(f"build {gch}: pch {_e(source)} | {_e(PCH_SUM_NAME)}")
+    if src_flags:
+        lines.append(f"  flags = {' '.join(src_flags)}")
+    lines.append(f"srccxxflags = {' '.join([*src_flags, *pch_consumer_flags()])}")
+    return ("$srccxxflags", gch)
+
+
+def ar_rule_lines(ar: Path | str) -> list[str]:
+    return [
+        "rule ar",
+        f"  command = $python $buildtool ar {_q(ar)} $out $out.rsp",
+        "  rspfile = $out.rsp",
+        "  rspfile_content = $in_newline",
+        "  description = AR $out",
+    ]
+
+
+def compile_edges(
+    lines: list[str],
+    sources: list[Path],
+    root: Path,
+    group: str,
+    flags: str = "",
+    own_includes: str = "",
+    cxx_override: tuple[str, str] | None = None,
+) -> list[str]:
+    """Emit compile edges for ``sources``; return the object paths.
+
+    ``cxx_override`` is a (flags, implicit-dep) pair applied to C++ edges
+    only, replacing ``flags`` (used for the precompiled header).
+    """
+    objects = []
+    for src in sources:
+        rel = src.relative_to(root).as_posix()
+        obj = f"obj/{group}/{rel}.o"
+        escaped_obj = _e(obj)
+        kind = SOURCE_KIND_FOR_SUFFIX[src.suffix]
+        override = cxx_override if kind == "cxx" else None
+        implicit = f" | {override[1]}" if override else ""
+        lines.append(f"build {escaped_obj}: {kind} {_e(src)}{implicit}")
+        if own_includes:
+            lines.append(f"  own_includes = {own_includes}")
+        if edge_flags := override[0] if override else flags:
+            lines.append(f"  flags = {edge_flags}")
+        # Escaped once here: the returned paths only ever appear in build
+        # statements (archive/link inputs), which use ninja escaping
+        objects.append(escaped_obj)
+    return objects
+
+
+def library_edges(
+    lines: list[str], libraries: list[ArduinoLibrary]
+) -> tuple[list[str], list[str]]:
+    """Emit every library's compile and archive edges.
+
+    Returns the archive names and the objects that link directly. A
+    library's own include dirs lead its compile lines, as PlatformIO searched
+    them first: the include path is one global list, so another library's
+    header of the same name would shadow them.
+    """
+    archives: list[str] = []
+    direct_objs: list[str] = []
+    for lib in libraries:
+        if not lib.sources:
+            # Header-only libraries are legitimate; the log makes an empty
+            # srcFilter or broken tree traceable before link errors do
+            _LOGGER.debug(
+                "Library %s has no source files; contributing includes only",
+                lib.name,
+            )
+            continue
+        objs = compile_edges(
+            lines,
+            lib.sources,
+            common_parent(lib.sources),
+            f"lib/{lib.name}",
+            flags=" ".join(_shell_token(f) for f in lib.flags),
+            own_includes=" ".join(f"-I{_q(d)}" for d in lib.include_dirs),
+        )
+        if not lib.lib_archive:
+            # libArchive: false / dot_a_linkage=false: hand the objects to
+            # the linker directly so unreferenced-but-required symbols
+            # (exception handlers, weak overrides) survive
+            direct_objs.extend(objs)
+            continue
+        archive = f"lib{lib.name}.a"
+        lines.append(f"build {_e(archive)}: ar {' '.join(objs)}")
+        archives.append(archive)
+    return archives, direct_objs
+
+
+# One build flag: the flag, plus its argument when that is a separate token
+Flag = tuple[str, ...]
+
+# Flags whose path operand is the next token; gcc also takes it glued on
+PATH_ARG_FLAGS = ("-include", "-imacros", "-isystem", "-iquote", "-idirafter")
+# Flags whose path operand is glued on
+PATH_PREFIXES = ("-I", "-L", *PATH_ARG_FLAGS)
+
+
+def _anchor(path: str, base: Path) -> str:
+    if not path or Path(path).is_absolute():
+        return path
+    return str(base / path)
+
+
+def anchor_path_flag(flag: Flag, base: Path) -> Flag:
+    """Anchor a flag's relative path operand at ``base``.
+
+    PlatformIO ran the compiler from the build path; ninja runs it from
+    ``.pioenvs/<name>``, where a relative operand would point elsewhere.
+    """
+    name, *args = flag
+    if args:
+        if name in PATH_ARG_FLAGS:
+            return (name, _anchor(args[0], base))
+        return flag
+    for prefix in PATH_PREFIXES:
+        if name.startswith(prefix):
+            return (prefix + _anchor(name[len(prefix) :], base),)
+    return flag
@@ -0,0 +1,248 @@
+"""Shared precompiled header policy for the build backends."""
+
+from __future__ import annotations
+
+from collections.abc import Iterable, Sequence
+import hashlib
+import logging
+import os
+from pathlib import Path
+import posixpath
+import re
+import subprocess
+import sys
+
+from esphome.build_helpers.ccache import effective_ccache_basedir, parse_enable_env
+from esphome.const import PLATFORM_NRF52
+from esphome.helpers import write_file_if_changed
+
+_LOGGER = logging.getLogger(__name__)
+
+# The header and its sidecars live in the build directory
+PCH_HEADER_NAME = "esphome_pch.h"
+PCH_GCH_NAME = f"{PCH_HEADER_NAME}.gch"
+# ccache hashes this instead of the .gch; also the freshness stamp
+PCH_SUM_NAME = f"{PCH_GCH_NAME}.sum"
+# The include list the .gch is compiled from
+PCH_SOURCE_NAME = "esphome_pch_src.h"
+
+# GCC can skip a .gch without a diagnostic and read the header of the same
+# name, so that header is an error. Other tools get the include list.
+PCH_GUARD_TEXT = f"""\
+#if defined(__GNUC__) && !defined(__clang__) && !defined(__INTELLISENSE__)
+#error "The precompiled header was not loaded"
+#else
+#include "{PCH_SOURCE_NAME}"
+#endif
+"""
+
+# The cc1plus wrapper the PlatformIO script writes on arm64 macOS
+PCH_CC1_DIR = "pch_cc1"
+
+# What the PlatformIO script leaves in the project root, for cleanup
+PCH_ARTIFACT_NAMES = (PCH_HEADER_NAME, PCH_GCH_NAME, PCH_SUM_NAME, PCH_SOURCE_NAME)
+PCH_ARTIFACT_DIRS = (PCH_CC1_DIR,)
+
+# The core headers every backend precompiles
+PCH_DEFAULT_HEADERS = ("esphome/core/pch_prefix.h",)
+
+# PlatformIO platforms that do not take the pch script
+PCH_SCRIPT_EXCLUDED_PLATFORMS = frozenset(
+    {
+        PLATFORM_NRF52,
+    }
+)
+
+# What ccache needs to cache compiles that load a .gch
+_CCACHE_PCH_SLOPPINESS = ("pch_defines", "time_macros")
+
+# Both include forms: an angle include resolving under src/ enters the digest
+_INCLUDE_RE = re.compile(rb'^\s*#\s*include\s+["<]([^">]+)[">]', re.MULTILINE)
+
+
+def pch_enabled() -> bool:
+    """Precompiled-header knob: default on, ``ESPHOME_PCH_ENABLE=0`` opts out."""
+    return parse_enable_env("ESPHOME_PCH_ENABLE") is not False
+
+
+def pch_forced() -> bool:
+    """``ESPHOME_PCH_ENABLE=1``: wanted even where the host rule says no."""
+    return parse_enable_env("ESPHOME_PCH_ENABLE") is True
+
+
+# GCC bug 14940: before these releases the Windows loader maps a .gch only
+# at its saved address. First fixed release per major, 16 on always fixed;
+# PCH_WINDOWS_CMAKE_OLD_GCC and the pch_usable message spell the same table
+PCH_WINDOWS_GCC_FIXED = {14: (14, 4), 15: (15, 3)}
+PCH_WINDOWS_GCC_FIXED_DEFAULT = (16, 0)
+# The same rule for CMake, which alone knows the version before configure
+PCH_WINDOWS_CMAKE_OLD_GCC = (
+    "CMAKE_CXX_COMPILER_VERSION VERSION_LESS 14.4 OR "
+    "(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 15 AND "
+    "CMAKE_CXX_COMPILER_VERSION VERSION_LESS 15.3)"
+)
+
+
+def gcc_relocates_pch_on_windows(version: Sequence[int]) -> bool:
+    """Whether a GCC of this version loads a .gch on Windows."""
+    if not version:
+        return False
+    fixed = PCH_WINDOWS_GCC_FIXED.get(version[0], PCH_WINDOWS_GCC_FIXED_DEFAULT)
+    return tuple(version[:2]) >= fixed
+
+
+# GCC ends the first --version line with its version; clang names itself
+_VERSION_RE = re.compile(r"\d+(?:\.\d+)+")
+
+
+def gcc_version(cxx: Sequence[Path | str]) -> tuple[int, ...] | None:
+    """The GCC version from ``--version``: () when it cannot be read, None
+    for a compiler that is not GCC."""
+    try:
+        result = subprocess.run(
+            [*cxx, "--version"], capture_output=True, text=True, check=False
+        )
+    except OSError as err:
+        _LOGGER.debug("Cannot run %s: %s", cxx[0], err)
+        return ()
+    banner = result.stdout.partition("\n")[0]
+    if "clang" in banner.lower():
+        return None
+    found = _VERSION_RE.findall(banner)
+    return tuple(int(part) for part in found[-1].split(".")) if found else ()
+
+
+def pch_needs_gcc_check() -> bool:
+    """Windows host with the knob unset: the compiler version decides."""
+    return sys.platform == "win32" and parse_enable_env("ESPHOME_PCH_ENABLE") is None
+
+
+def pch_usable(cxx: Sequence[Path | str]) -> bool:
+    """The knob plus the host rule; ``ESPHOME_PCH_ENABLE=1`` skips the rule."""
+    if not pch_enabled():
+        return False
+    if not pch_needs_gcc_check():
+        return True
+    version = gcc_version(cxx)
+    if version is None or gcc_relocates_pch_on_windows(version):
+        return True
+    _LOGGER.info(
+        "GCC %s cannot load a precompiled header on Windows (GCC bug 14940, "
+        "fixed in 14.4, 15.3 and 16); compiling without it "
+        "(set ESPHOME_PCH_ENABLE=1 to force)",
+        ".".join(map(str, version)) or "of unknown version",
+    )
+    return False
+
+
+def pch_consumer_flags() -> list[str]:
+    """Flags a C++ src compile loads the pch with. The -include stays
+    relative: an absolute path would enter the ccache key."""
+    return ["-Winvalid-pch", "-Werror=invalid-pch", "-include", PCH_HEADER_NAME]
+
+
+def ccache_pch_env() -> dict[str, str]:
+    """What ccache needs to cache compiles that load a .gch, added to what
+    the user already set."""
+    if not pch_enabled():
+        return {}
+    sloppiness = [
+        item.strip()
+        for item in os.environ.get("CCACHE_SLOPPINESS", "").split(",")
+        if item.strip()
+    ]
+    sloppiness += [item for item in _CCACHE_PCH_SLOPPINESS if item not in sloppiness]
+    env = {"CCACHE_SLOPPINESS": ",".join(sloppiness)}
+    if "CCACHE_PCH_EXTSUM" not in os.environ:
+        env["CCACHE_PCH_EXTSUM"] = "true"
+    return env
+
+
+def pch_script_enabled() -> bool:
+    """Whether this PlatformIO build takes the pch script."""
+    from esphome.core import CORE
+
+    return pch_enabled() and CORE.target_platform not in PCH_SCRIPT_EXCLUDED_PLATFORMS
+
+
+def pch_header_text(include_headers: Iterable[str]) -> str:
+    """The prefix-header source: exactly these includes, in order."""
+    return "".join(f'#include "{name}"\n' for name in include_headers)
+
+
+def write_pch_headers(build_dir: Path, include_headers: Iterable[str]) -> Path:
+    """Write the guard header and the include list; return the latter,
+    which is what the .gch compiles from."""
+    write_file_if_changed(build_dir / PCH_HEADER_NAME, PCH_GUARD_TEXT)
+    source = build_dir / PCH_SOURCE_NAME
+    write_file_if_changed(source, pch_header_text(include_headers))
+    return source
+
+
+def _include_closure(src_dir: Path, roots: Iterable[str]) -> dict[str, bytes]:
+    """Include closure of ``roots``: src-relative name -> contents.
+
+    Resolution mirrors the compiler (includer's dir, then src root). No
+    #ifdef evaluation: including too much is the safe direction. Headers
+    outside ``src_dir`` are covered by the version strings of the caller.
+    """
+    seen: dict[str, bytes] = {}
+    stack: list[tuple[str, str]] = [(name, "") for name in roots]
+    while stack:
+        name, from_dir = stack.pop()
+        for candidate in (f"{from_dir}/{name}" if from_dir else name, name):
+            rel = posixpath.normpath(candidate)
+            if not rel.startswith("..") and (src_dir / rel).is_file():
+                break
+        else:
+            continue
+        if rel in seen:
+            continue
+        data = seen[rel] = (src_dir / rel).read_bytes()
+        parent = posixpath.dirname(rel)
+        stack.extend((inc.decode(), parent) for inc in _INCLUDE_RE.findall(data))
+    return seen
+
+
+def pch_checksum(
+    src_dir: Path, include_headers: Iterable[str], extra: Iterable[str]
+) -> str:
+    """Digest of the prefix header's include closure plus ``extra``."""
+    digest = hashlib.sha256()
+    closure = _include_closure(src_dir, include_headers)
+    for name in sorted(closure):
+        digest.update(name.encode())
+        digest.update(closure[name])
+        digest.update(b"\0")
+    for item in extra:
+        digest.update(item.encode())
+        digest.update(b"\0")
+    return digest.hexdigest()
+
+
+def pch_identity(
+    tokens: Iterable[str],
+    src_dir: Path,
+    include_headers: tuple[str, ...],
+    extra: Iterable[str],
+) -> str:
+    """The .sum digest: include closure, header text, ``extra`` and the
+    compile flags with the build path stripped, as ccache does."""
+    from esphome.core import CORE
+
+    flags = (
+        " ".join(tokens)
+        .replace(str(CORE.build_path), "")
+        .replace(effective_ccache_basedir(), "")
+    )
+    # The closure is sorted, so header order only enters via the text
+    return pch_checksum(
+        src_dir, include_headers, (pch_header_text(include_headers), *extra, flags)
+    )
+
+
+_DISABLE_HINT = " (set ESPHOME_PCH_ENABLE=0 to disable)"
+
+
+def log_pch_in_use() -> None:
+    _LOGGER.info("Compiling with a precompiled header%s", _DISABLE_HINT)
@@ -0,0 +1,180 @@
+"""Run a native build tool (cmake, ninja) and relay its output.
+
+Output is read from a pipe so it can be filtered here: a child that inherits
+our stdout writes straight to the file descriptor, past any Python wrapper.
+"""
+
+from __future__ import annotations
+
+import codecs
+from contextlib import suppress
+import logging
+import os
+from pathlib import Path
+import re
+import shutil
+import subprocess
+import sys
+from typing import Any, TextIO
+
+from esphome.util import ANSI_ESCAPE, RedirectText, shlex_quote
+
+_LOGGER = logging.getLogger(__name__)
+
+# Windows code page identifier for UTF-8, as used by ``chcp 65001``.
+UTF8_CODEPAGE = 65001
+
+# Same pattern idf.py uses to spot ninja status lines (``is_progression``).
+_PROGRESS = re.compile(r"^\[\d+/\d+\]|.*\(\d+ \%\)$")
+_READ_SIZE = 65536
+
+
+def _get_kernel32() -> Any | None:
+    """Return the Windows kernel32 module, or None on any other platform."""
+    if sys.platform != "win32":
+        return None
+    import ctypes
+
+    return ctypes.windll.kernel32
+
+
+class Utf8Console:
+    """Keep an attached Windows console on UTF-8 while a build tool runs.
+
+    esp_idf_size draws its table with Unicode box characters, and CMake
+    re-decodes a child's output with the console code page, which garbles the
+    table on any page but UTF-8. A console already on UTF-8 is left alone so
+    an overlapping build never records UTF-8 as the page to go back to.
+    """
+
+    def __init__(self, kernel32: Any | None) -> None:
+        self._kernel32 = kernel32
+        self._codepages: tuple[int, int] | None = None
+
+    def __enter__(self) -> None:
+        kernel32 = self._kernel32
+        if kernel32 is None:
+            return
+        old_in = kernel32.GetConsoleCP()
+        old_out = kernel32.GetConsoleOutputCP()
+        # Both calls return 0 when no console is attached.
+        if not old_in or not old_out:
+            return
+        if old_in == UTF8_CODEPAGE and old_out == UTF8_CODEPAGE:
+            return
+        # Record first so a switch that fails part way is still undone.
+        self._codepages = (old_in, old_out)
+        kernel32.SetConsoleCP(UTF8_CODEPAGE)
+        kernel32.SetConsoleOutputCP(UTF8_CODEPAGE)
+
+    def __exit__(self, *exc_info: object) -> None:
+        if self._codepages is None:
+            return
+        old_in, old_out = self._codepages
+        self._codepages = None
+        self._kernel32.SetConsoleCP(old_in)
+        self._kernel32.SetConsoleOutputCP(old_out)
+
+
+def _fit_terminal(text: str) -> str:
+    """Elide the middle of ``text`` to fit the terminal, as idf.py does.
+
+    A width of 0 (a pipe, the dashboard) leaves the text whole.
+    """
+    width = shutil.get_terminal_size((0, 0)).columns
+    if not width:
+        return text
+    if width <= 3:
+        return "." * width
+    if len(text) >= width:
+        keep = (width - 3) // 2
+        return f"{text[:keep]}...{text[len(text) - keep :]}"
+    return text
+
+
+class ToolOutput(RedirectText):
+    """RedirectText that can collapse ninja status lines into one line.
+
+    With ``progress`` each ``[n/m]`` line overwrites the previous one, the
+    way idf.py shows a build.
+    """
+
+    def __init__(
+        self, out: TextIO, filter_lines: list[str] | None, progress: bool
+    ) -> None:
+        super().__init__(out, filter_lines=filter_lines)
+        self._progress = progress
+        self._on_progress_line = False
+
+    def _splits_lines(self) -> bool:
+        return self._progress or super()._splits_lines()
+
+    def _emit_line(self, line: str) -> None:
+        if self._progress and _PROGRESS.match(line):
+            if not self._is_filtered(line):
+                text = _fit_terminal(line.strip("\r\n"))
+                self._write_color_replace(f"\r{text}\x1b[K")
+                self._on_progress_line = True
+            return
+        self._end_progress_line()
+        super()._emit_line(line)
+
+    def _end_progress_line(self) -> None:
+        if self._on_progress_line:
+            self._on_progress_line = False
+            self._write_color_replace(os.linesep)
+
+    def drain(self) -> None:
+        super().drain()
+        # Called from cleanup, so a broken stream must not hide the exit code.
+        with suppress(OSError, ValueError):
+            self._end_progress_line()
+            self._out.flush()
+
+
+def run_build_tool(
+    cmd: list[str],
+    *,
+    cwd: Path,
+    env: dict[str, str],
+    filter_lines: list[str] | None = None,
+    progress: bool = False,
+    log_path: Path | None = None,
+) -> int:
+    """Run ``cmd`` and relay stdout and stderr, merged, to our stdout.
+
+    ``log_path`` also gets the full, unfiltered output without color codes, as
+    idf.py wrote its logs (its hint patterns expect plain text). Returns the
+    exit code.
+    """
+    _LOGGER.debug("Running: %s", " ".join(shlex_quote(arg) for arg in cmd))
+    _LOGGER.debug("  in directory: %s", cwd)
+    output = ToolOutput(sys.stdout, filter_lines, progress)
+    decoder = codecs.getincrementaldecoder("utf-8")(errors="replace")
+    if log_path is not None:
+        log_path.parent.mkdir(parents=True, exist_ok=True)
+    with (
+        Path(log_path or os.devnull).open("w", encoding="utf-8", newline="") as log,
+        Utf8Console(_get_kernel32()),
+        subprocess.Popen(
+            cmd,
+            cwd=cwd,
+            env=env,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.STDOUT,
+            close_fds=False,
+        ) as proc,
+    ):
+        try:
+            # read1 returns as soon as anything is available, so output
+            # streams while the tool runs.
+            while chunk := proc.stdout.read1(_READ_SIZE):
+                text = decoder.decode(chunk)
+                log.write(ANSI_ESCAPE.sub("", text))
+                output.write(text)
+            if tail := decoder.decode(b"", final=True):
+                log.write(ANSI_ESCAPE.sub("", tail))
+                output.write(tail)
+        finally:
+            output.drain()
+    return proc.returncode
@@ -16,8 +16,8 @@ def tools_cache_path(env_var: str, subdir: str) -> Path:
    from esphome.helpers import get_str_env

    if prefix := get_str_env(env_var, "").strip():
-        # resolve(): symlinked prefixes otherwise trip idf.py's
-        # venv-mismatch warning on every build
+        # resolve(): a symlinked prefix would otherwise record a second
+        # spelling of the same paths in the build tree
        return Path(prefix).expanduser().resolve()
    # appauthor=False keeps the Windows path short (no vendor segment);
    # deep IDF trees run into MAX_PATH otherwise
@@ -33,4 +33,14 @@ def tools_cache_path(env_var: str, subdir: str) -> Path:
 IDF_TOOLS_CACHE = ("ESPHOME_ESP_IDF_PREFIX", "idf")
 SDK_NRF_TOOLS_CACHE = ("ESPHOME_SDK_NRF_PREFIX", "sdk-nrf")
 ARDUINO8266_TOOLS_CACHE = ("ESPHOME_ARDUINO8266_PREFIX", "arduino8266")
-TOOLS_CACHE_SPECS = (IDF_TOOLS_CACHE, SDK_NRF_TOOLS_CACHE, ARDUINO8266_TOOLS_CACHE)
+# The host backend installs nothing; the entry only holds its ccache dir
+HOST_TOOLS_CACHE = ("ESPHOME_HOST_PREFIX", "host")
+# PlatformIO installs into its own dirs; the entry is its ccache dir itself
+PLATFORMIO_CCACHE = ("ESPHOME_PLATFORMIO_CCACHE_DIR", "platformio-ccache")
+TOOLS_CACHE_SPECS = (
+    IDF_TOOLS_CACHE,
+    SDK_NRF_TOOLS_CACHE,
+    ARDUINO8266_TOOLS_CACHE,
+    HOST_TOOLS_CACHE,
+    PLATFORMIO_CCACHE,
+)
@@ -0,0 +1,2 @@
+"""Commands of the esphome command line, one module each, imported by
+__main__ only when they run so that startup stays light."""
@@ -0,0 +1,164 @@
+"""``esphome rename``."""
+
+from __future__ import annotations
+
+import argparse
+from pathlib import Path
+import re
+
+from esphome import yaml_edit, yaml_util
+from esphome.const import (
+    ALLOWED_NAME_CHARS,
+    CONF_ESPHOME,
+    CONF_NAME,
+    CONF_SUBSTITUTIONS,
+)
+from esphome.core import CORE, EsphomeError
+from esphome.log import AnsiFore, color
+from esphome.types import ConfigType
+from esphome.util import ESPHOME_COMMAND, run_external_process, safe_print
+
+
+def _revert(new_path: Path, why: str) -> int:
+    """Say why the rename stopped and take the new file back; an orphan the
+    next attempt would trip over is reported."""
+    safe_print(color(AnsiFore.BOLD_RED, f"Rename failed: {why}"))
+    try:
+        new_path.unlink(missing_ok=True)
+    except OSError as err:
+        safe_print(color(AnsiFore.BOLD_RED, f"Could not remove {new_path}: {err}"))
+    return 1
+
+
+def command_rename(args: argparse.Namespace, config: ConfigType) -> int | None:
+    """Rename the device: a new file with the name line rewritten, validated
+    and installed, then the old file removed."""
+    new_name = args.name
+    for c in new_name:
+        if c not in ALLOWED_NAME_CHARS:
+            safe_print(
+                color(
+                    AnsiFore.BOLD_RED,
+                    f"'{c}' is an invalid character for names. Valid characters are: "
+                    f"{ALLOWED_NAME_CHARS} (lowercase, no spaces)",
+                )
+            )
+            return 1
+
+    yaml = yaml_util.load_yaml(CORE.config_path)
+
+    def name_edit() -> tuple[str, yaml_edit.LineEdit]:
+        """The name and the line to rewrite: the name's own line, or the
+        substitution's line it comes from, as a plain value in this file."""
+        esphome_conf = yaml.get(CONF_ESPHOME)
+        if not isinstance(esphome_conf, dict) or CONF_NAME not in esphome_conf:
+            raise EsphomeError(f"no '{CONF_ESPHOME}: {CONF_NAME}:' in the file")
+        old_name = str(esphome_conf[CONF_NAME])
+        mapping, field = esphome_conf, CONF_NAME
+        if match := re.match(r"^\$\{?([a-zA-Z0-9_]+)\}?$", old_name):
+            mapping, field = yaml.get(CONF_SUBSTITUTIONS), match.group(1)
+            if not isinstance(mapping, dict) or field not in mapping:
+                raise EsphomeError(f"the substitution '{field}' is not in the file")
+            old_name = str(mapping[field])
+        # Only read here; the rewritten text goes to a new file, so the
+        # source may live anywhere the config path points to
+        source = yaml_edit.source_of(mapping, field)
+        if source is None or source[0].resolve() != CORE.config_path.resolve():
+            raise EsphomeError(f"'{field}' was not read from {CORE.config_path}")
+        doc, line_no = source
+        text = yaml_edit.line_at(doc, line_no)
+        if (line_match := yaml_edit.field_line_re(field, old_name).match(text)) is None:
+            raise EsphomeError(f"'{field}' is not a plain value on {doc}:{line_no + 1}")
+        # The new value is always quoted, whatever the old line had
+        return old_name, yaml_edit.LineEdit(
+            doc, line_no, text, yaml_edit.rewrite(line_match, new_name, '"')
+        )
+
+    try:
+        old_name, edit = name_edit()
+    except EsphomeError as err:
+        safe_print(
+            color(
+                AnsiFore.BOLD_RED,
+                f"Complex YAML files cannot be automatically renamed: {err}",
+            )
+        )
+        return 1
+
+    # ``new_name == old_name`` (after substitution resolution) is
+    # a no-op rewrite that would still queue a pointless re-flash.
+    # Catch it before the path-equality check below — covers the
+    # case where the config filename doesn't match the device name
+    # (e.g. ``weird-file.yaml`` whose ``esphome.name`` is
+    # ``kitchen``; running ``esphome rename weird-file.yaml kitchen``
+    # would otherwise just re-flash the same hostname).
+    if new_name == old_name:
+        safe_print(
+            color(
+                AnsiFore.BOLD_RED,
+                f"'{new_name}' is already the device's name.",
+            )
+        )
+        return 1
+
+    new_path: Path = CORE.config_dir / (new_name + ".yaml")
+    if new_path.resolve() == CORE.config_path.resolve():
+        safe_print(
+            color(
+                AnsiFore.BOLD_RED,
+                f"'{new_name}' is already the device's name.",
+            )
+        )
+        return 1
+    if new_path.exists():
+        safe_print(
+            color(
+                AnsiFore.BOLD_RED,
+                f"Cannot rename: {new_path} already exists. "
+                "Refusing to overwrite an existing configuration.",
+            )
+        )
+        return 1
+    safe_print(
+        f"Updating {color(AnsiFore.CYAN, str(CORE.config_path))} to {color(AnsiFore.CYAN, str(new_path))}"
+    )
+    print()
+
+    try:
+        yaml_edit.write_keeping_mode(
+            new_path,
+            yaml_edit.rewritten_text(yaml_edit.read_text(CORE.config_path), [edit]),
+            like=CORE.config_path,
+        )
+    except EsphomeError as err:
+        return _revert(new_path, str(err))
+
+    if run_external_process(*ESPHOME_COMMAND, "config", str(new_path)) != 0:
+        return _revert(new_path, "the new configuration does not validate")
+
+    cli_args = [
+        "run",
+        str(new_path),
+        "--no-logs",
+        "--device",
+        CORE.address,
+    ]
+
+    if args.dashboard:
+        cli_args.insert(0, "--dashboard")
+
+    try:
+        rc = run_external_process(*ESPHOME_COMMAND, *cli_args)
+    except KeyboardInterrupt:
+        rc = 1
+    if rc != 0:
+        return _revert(
+            new_path,
+            "the install did not finish; the device may already run the new name",
+        )
+
+    CORE.config_path.unlink()
+
+    safe_print(color(AnsiFore.BOLD_GREEN, "SUCCESS"))
+    print()
+    return 0
@@ -40,8 +40,10 @@ from esphome.cpp_generator import (  # noqa: F401
    progmem_array,
    safe_exp,
    set_cpp_standard,
+    shared_progmem_array,
    statement,
    static_const_array,
+    static_function,
    templatable,
    variable,
    with_local_variable,
@@ -62,16 +62,10 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    sens = await sensor.new_sensor(config[CONF_TVOC])
-    cg.add(var.set_tvoc(sens))
-
-    if version_config := config.get(CONF_VERSION):
-        sens = await sensor.new_sensor(version_config)
-        cg.add(var.set_version(sens))
-
-    if resistance_config := config.get(CONF_RESISTANCE):
-        sens = await sensor.new_sensor(resistance_config)
-        cg.add(var.set_resistance(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TVOC, var.set_tvoc)
+    await sensors(CONF_VERSION, var.set_version)
+    await sensors(CONF_RESISTANCE, var.set_resistance)


 AGS10_NEW_I2C_ADDRESS_SCHEMA = cv.maybe_simple_value(
@@ -57,10 +57,6 @@ async def to_code(config: ConfigType) -> None:
    await i2c.register_i2c_device(var, config)
    cg.add(var.set_variant(config[CONF_VARIANT]))

-    if temperature := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature)
-        cg.add(var.set_temperature_sensor(sens))
-
-    if humidity := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity)
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
@@ -85,20 +85,11 @@ async def wave_base_to_code(var: MockObj, config: ConfigType) -> None:

    await ble_client.register_ble_node(var, config)

-    if config_humidity := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(config_humidity)
-        cg.add(var.set_humidity(sens))
-    if config_temperature := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(config_temperature)
-        cg.add(var.set_temperature(sens))
-    if config_pressure := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(config_pressure)
-        cg.add(var.set_pressure(sens))
-    if config_tvoc := config.get(CONF_TVOC):
-        sens = await sensor.new_sensor(config_tvoc)
-        cg.add(var.set_tvoc(sens))
-    if config_battery_voltage := config.get(CONF_BATTERY_VOLTAGE):
-        sens = await sensor.new_sensor(config_battery_voltage)
-        cg.add(var.set_battery_voltage(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_HUMIDITY, var.set_humidity)
+    await sensors(CONF_TEMPERATURE, var.set_temperature)
+    await sensors(CONF_PRESSURE, var.set_pressure)
+    await sensors(CONF_TVOC, var.set_tvoc)
+    await sensors(CONF_BATTERY_VOLTAGE, var.set_battery_voltage)
    if config_battery_update_interval := config.get(CONF_BATTERY_UPDATE_INTERVAL):
        cg.add(var.set_battery_update_interval(config_battery_update_interval))
@@ -87,16 +87,9 @@ async def to_code(config: ConfigType) -> None:
    var = cg.new_Pvariable(config[CONF_ID])
    await airthings_wave_base.wave_base_to_code(var, config)

-    if config_radon := config.get(CONF_RADON):
-        sens = await sensor.new_sensor(config_radon)
-        cg.add(var.set_radon(sens))
-    if config_radon_long_term := config.get(CONF_RADON_LONG_TERM):
-        sens = await sensor.new_sensor(config_radon_long_term)
-        cg.add(var.set_radon_long_term(sens))
-    if config_co2 := config.get(CONF_CO2):
-        sens = await sensor.new_sensor(config_co2)
-        cg.add(var.set_co2(sens))
-    if config_illuminance := config.get(CONF_ILLUMINANCE):
-        sens = await sensor.new_sensor(config_illuminance)
-        cg.add(var.set_illuminance(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_RADON, var.set_radon)
+    await sensors(CONF_RADON_LONG_TERM, var.set_radon_long_term)
+    await sensors(CONF_CO2, var.set_co2)
+    await sensors(CONF_ILLUMINANCE, var.set_illuminance)
    cg.add(var.set_device_type(config[CONF_DEVICE_TYPE]))
@@ -74,26 +74,10 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await ble_client.register_ble_node(var, config)

-    if flow_config := config.get(CONF_FLOW):
-        sens = await sensor.new_sensor(flow_config)
-        cg.add(var.set_flow_sensor(sens))
-
-    if head_config := config.get(CONF_HEAD):
-        sens = await sensor.new_sensor(head_config)
-        cg.add(var.set_head_sensor(sens))
-
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
-
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-
-    if speed_config := config.get(CONF_SPEED):
-        sens = await sensor.new_sensor(speed_config)
-        cg.add(var.set_speed_sensor(sens))
-
-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_FLOW, var.set_flow_sensor)
+    await sensors(CONF_HEAD, var.set_head_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_SPEED, var.set_speed_sensor)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
@@ -46,10 +46,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
-
-    if humidity_config := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity_config)
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
@@ -48,10 +48,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
-
-    if humidity_config := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity_config)
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
@@ -48,10 +48,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await ble_client.register_ble_node(var, config)

-    if battery_level_config := config.get(CONF_BATTERY_LEVEL):
-        sens = await sensor.new_sensor(battery_level_config)
-        cg.add(var.set_battery(sens))
-
-    if illuminance_config := config.get(CONF_ILLUMINANCE):
-        sens = await sensor.new_sensor(illuminance_config)
-        cg.add(var.set_illuminance(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_BATTERY_LEVEL, var.set_battery)
+    await sensors(CONF_ILLUMINANCE, var.set_illuminance)
@@ -13,6 +13,7 @@ from esphome.components.logger import request_log_listener
 from esphome.components.noise import (  # noqa: F401
    ENCRYPTION_SCHEMA,
    decode_encryption_key,
+    enable_spare_ephemeral,
    encryption_schema,
    new_psk_progmem,
    validate_encryption_key,
@@ -600,7 +601,7 @@ async def to_code(config: ConfigType) -> None:

    if (encryption_config := config.get(CONF_ENCRYPTION, None)) is not None:
        if key := encryption_config.get(CONF_KEY):
-            cg.add(var.set_noise_psk(new_psk_progmem(config[CONF_ID], key)))
+            cg.add(var.set_noise_psk(new_psk_progmem(key)))
            cg.add_define("USE_API_NOISE_PSK_FROM_YAML")
        else:
            # No key provided, but encryption desired
@@ -613,6 +614,7 @@ async def to_code(config: ConfigType) -> None:
            # and plaintext disabled. Only a factory reset can remove it.
            cg.add_define("USE_API_PLAINTEXT")
        cg.add_define("USE_API_NOISE")
+        enable_spare_ephemeral()
    else:
        cg.add_define("USE_API_PLAINTEXT")

@@ -317,9 +317,15 @@ class APIConnection final : public APIServerConnectionBase {
  void on_noise_encryption_set_key_request(const NoiseEncryptionSetKeyRequest &msg);
 #endif

+  // How long a new connection holds off the spare ephemeral refill
+  static constexpr uint32_t CONNECT_GRACE_MS = 1000;
  bool is_authenticated() {
    return static_cast<ConnectionState>(this->flags_.connection_state) == ConnectionState::AUTHENTICATED;
  }
+  // An older unauthenticated connection is a stale half open client and does not count
+  bool is_still_connecting(uint32_t now) {
+    return !this->is_authenticated() && now - this->last_traffic_ < CONNECT_GRACE_MS;
+  }
  bool is_connection_setup() {
    return static_cast<ConnectionState>(this->flags_.connection_state) == ConnectionState::CONNECTED ||
           this->is_authenticated();
@@ -162,6 +162,13 @@ void APIServer::loop() {
    this->accept_new_connections_();
  }

+  const bool connected = network::is_connected();
+#ifdef USE_NOISE_SPARE_EPHEMERAL
+  if (connected && !noise::has_spare_ephemeral()) {
+    this->refill_spare_ephemeral_();
+  }
+#endif
+
  if (this->api_connection_count_ == 0) {
    // Check reboot timeout - done in loop to avoid scheduler heap churn
    // (cancelled scheduler items sit in heap memory until their scheduled time).
@@ -178,8 +185,7 @@ void APIServer::loop() {
  }

  // Process clients and remove disconnected ones in a single pass
-  // Check network connectivity once for all clients
-  if (!network::is_connected()) {
+  if (!connected) {
    // Network is down - disconnect all clients
    for (auto &client : this->active_clients()) {
      client->on_fatal_error();
@@ -207,6 +213,19 @@ void APIServer::loop() {
  }
 }

+#ifdef USE_NOISE_SPARE_EPHEMERAL
+// An OTA handshake is not visible here and just pays the refill it triggered
+void APIServer::refill_spare_ephemeral_() {
+  const uint32_t now = App.get_loop_component_start_time();
+  for (auto &client : this->active_clients()) {
+    if (client->is_still_connecting(now)) {
+      return;
+    }
+  }
+  noise::prepare_spare_ephemeral();
+}
+#endif
+
 void APIServer::remove_client_(uint8_t client_index) {
  auto &client = this->clients_[client_index];

@@ -5,7 +5,7 @@
 #include "api_buffer.h"
 // Must precede clients_ so APIConnection is complete for default_delete (libc++).
 #include "api_connection.h"
-#ifdef USE_API_NOISE
+#if defined(USE_API_NOISE) || defined(USE_NOISE_SPARE_EPHEMERAL)
 // Only present in the build when the noise component is loaded
 #include "esphome/components/noise/noise.h"
 #endif
@@ -367,6 +367,9 @@ class APIServer final : public Component
  uint8_t provisioning_source_{0};
 #endif

+#ifdef USE_NOISE_SPARE_EPHEMERAL
+  void refill_spare_ephemeral_();
+#endif
 #ifdef USE_API_NOISE
  noise::NoiseContext noise_ctx_;
 #ifndef USE_API_NOISE_PSK_FROM_YAML
@@ -35,10 +35,6 @@ CONFIG_SCHEMA = cv.Schema(
 async def to_code(config: ConfigType) -> None:
    hub = await cg.get_variable(config[CONF_AS3935_ID])

-    if distance_config := config.get(CONF_DISTANCE):
-        sens = await sensor.new_sensor(distance_config)
-        cg.add(hub.set_distance_sensor(sens))
-
-    if lightning_energy_config := config.get(CONF_LIGHTNING_ENERGY):
-        sens = await sensor.new_sensor(lightning_energy_config)
-        cg.add(hub.set_energy_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_DISTANCE, hub.set_distance_sensor)
+    await sensors(CONF_LIGHTNING_ENERGY, hub.set_energy_sensor)
@@ -87,18 +87,8 @@ async def to_code(config: ConfigType) -> None:
    if out_of_range_mode_config := config.get(CONF_OUT_OF_RANGE_MODE):
        cg.add(var.set_out_of_range_mode(out_of_range_mode_config))

-    if raw_position_config := config.get(CONF_RAW_POSITION):
-        sens = await sensor.new_sensor(raw_position_config)
-        cg.add(var.set_raw_position_sensor(sens))
-
-    if gain_config := config.get(CONF_GAIN):
-        sens = await sensor.new_sensor(gain_config)
-        cg.add(var.set_gain_sensor(sens))
-
-    if magnitude_config := config.get(CONF_MAGNITUDE):
-        sens = await sensor.new_sensor(magnitude_config)
-        cg.add(var.set_magnitude_sensor(sens))
-
-    if status_config := config.get(CONF_STATUS):
-        sens = await sensor.new_sensor(status_config)
-        cg.add(var.set_status_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_RAW_POSITION, var.set_raw_position_sensor)
+    await sensors(CONF_GAIN, var.set_gain_sensor)
+    await sensors(CONF_MAGNITUDE, var.set_magnitude_sensor)
+    await sensors(CONF_STATUS, var.set_status_sensor)
@@ -85,18 +85,9 @@ async def to_code(config: ConfigType) -> None:

    cg.add(var.set_address(config[CONF_MAC_ADDRESS].as_hex))

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature(sens))
-    if humidity_config := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity_config)
-        cg.add(var.set_humidity(sens))
-    if battery_level_config := config.get(CONF_BATTERY_LEVEL):
-        sens = await sensor.new_sensor(battery_level_config)
-        cg.add(var.set_battery_level(sens))
-    if battery_voltage_config := config.get(CONF_BATTERY_VOLTAGE):
-        sens = await sensor.new_sensor(battery_voltage_config)
-        cg.add(var.set_battery_voltage(sens))
-    if signal_strength_config := config.get(CONF_SIGNAL_STRENGTH):
-        sens = await sensor.new_sensor(signal_strength_config)
-        cg.add(var.set_signal_strength(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature)
+    await sensors(CONF_HUMIDITY, var.set_humidity)
+    await sensors(CONF_BATTERY_LEVEL, var.set_battery_level)
+    await sensors(CONF_BATTERY_VOLTAGE, var.set_battery_voltage)
+    await sensors(CONF_SIGNAL_STRENGTH, var.set_signal_strength)
@@ -129,30 +129,15 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await spi.register_spi_device(var, config)

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
-    if reactive_power_config := config.get(CONF_REACTIVE_POWER):
-        sens = await sensor.new_sensor(reactive_power_config)
-        cg.add(var.set_reactive_power_sensor(sens))
-    if power_factor_config := config.get(CONF_POWER_FACTOR):
-        sens = await sensor.new_sensor(power_factor_config)
-        cg.add(var.set_power_factor_sensor(sens))
-    if forward_active_energy_config := config.get(CONF_FORWARD_ACTIVE_ENERGY):
-        sens = await sensor.new_sensor(forward_active_energy_config)
-        cg.add(var.set_forward_active_energy_sensor(sens))
-    if reverse_active_energy_config := config.get(CONF_REVERSE_ACTIVE_ENERGY):
-        sens = await sensor.new_sensor(reverse_active_energy_config)
-        cg.add(var.set_reverse_active_energy_sensor(sens))
-    if frequency_config := config.get(CONF_FREQUENCY):
-        sens = await sensor.new_sensor(frequency_config)
-        cg.add(var.set_freq_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)
+    await sensors(CONF_REACTIVE_POWER, var.set_reactive_power_sensor)
+    await sensors(CONF_POWER_FACTOR, var.set_power_factor_sensor)
+    await sensors(CONF_FORWARD_ACTIVE_ENERGY, var.set_forward_active_energy_sensor)
+    await sensors(CONF_REVERSE_ACTIVE_ENERGY, var.set_reverse_active_energy_sensor)
+    await sensors(CONF_FREQUENCY, var.set_freq_sensor)
    cg.add(var.set_line_freq(config[CONF_LINE_FREQUENCY]))
    cg.add(var.set_meter_constant(config[CONF_METER_CONSTANT]))
    cg.add(var.set_pl_const(config[CONF_PL_CONST]))
@@ -241,12 +241,9 @@ async def to_code(config: ConfigType) -> None:
        if peak_current_config := conf.get(CONF_PEAK_CURRENT):
            sens = await sensor.new_sensor(peak_current_config)
            cg.add(var.set_peak_current_sensor(i, sens))
-    if frequency_config := config.get(CONF_FREQUENCY):
-        sens = await sensor.new_sensor(frequency_config)
-        cg.add(var.set_freq_sensor(sens))
-    if chip_temperature_config := config.get(CONF_CHIP_TEMPERATURE):
-        sens = await sensor.new_sensor(chip_temperature_config)
-        cg.add(var.set_chip_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_FREQUENCY, var.set_freq_sensor)
+    await sensors(CONF_CHIP_TEMPERATURE, var.set_chip_temperature_sensor)
    cg.add(var.set_line_freq(config[CONF_LINE_FREQUENCY]))
    cg.add(var.set_current_phases(config[CONF_CURRENT_PHASES]))
    cg.add(var.set_pga_gain(config[CONF_GAIN_PGA]))
@@ -36,14 +36,13 @@ CONFIG_SCHEMA = cv.Schema(


 async def to_code(config: ConfigType) -> None:
-    parent = await cg.get_variable(config[CONF_ID])
+    hub = await cg.get_variable(config[CONF_ID])

    if phase_cfg := config.get(CONF_PHASE_STATUS):
        for i, key in enumerate(PHASE_KEYS):
            if sub_phase_cfg := phase_cfg.get(key):
                sens = await text_sensor.new_text_sensor(sub_phase_cfg)
-                cg.add(parent.set_phase_status_text_sensor(i, sens))
+                cg.add(hub.set_phase_status_text_sensor(i, sens))

-    if freq_status_config := config.get(CONF_FREQUENCY_STATUS):
-        sens = await text_sensor.new_text_sensor(freq_status_config)
-        cg.add(parent.set_freq_status_text_sensor(sens))
+    text_sensors = text_sensor.sub_text_sensors(config)
+    await text_sensors(CONF_FREQUENCY_STATUS, hub.set_freq_status_text_sensor)
@@ -14,6 +14,10 @@ class AudioDac {
  virtual bool is_muted() = 0;
  virtual float volume() = 0;

+  /// Called from the main loop by the speaker driving this DAC once its audio clocks are running.
+  /// DACs that can only be configured while clocked (e.g. DSP state lost across clock stops) override this.
+  virtual void on_audio_started() {}
+
 protected:
  bool is_muted_{false};
 };
@@ -44,10 +44,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await register_bedjet_child(var, config)

-    if outlet_temperature_sensor := config.get(CONF_OUTLET_TEMPERATURE):
-        sensor_var = await sensor.new_sensor(outlet_temperature_sensor)
-        cg.add(var.set_outlet_temperature_sensor(sensor_var))
-
-    if ambient_temperature_sensor := config.get(CONF_AMBIENT_TEMPERATURE):
-        sensor_var = await sensor.new_sensor(ambient_temperature_sensor)
-        cg.add(var.set_ambient_temperature_sensor(sensor_var))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_OUTLET_TEMPERATURE, var.set_outlet_temperature_sensor)
+    await sensors(CONF_AMBIENT_TEMPERATURE, var.set_ambient_temperature_sensor)
@@ -61,14 +61,16 @@ from esphome.const import (
    DEVICE_CLASS_VIBRATION,
    DEVICE_CLASS_WINDOW,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
 from esphome.core.entity_helpers import (
+    SubEntities,
    entity_duplicate_validator,
    queue_entity_register,
    setup_device_class,
    setup_entity,
 )
-from esphome.cpp_generator import MockObjClass
+from esphome.cpp_generator import MockObj, MockObjClass
+from esphome.types import ConfigType
 from esphome.util import Registry

 CODEOWNERS = ["@esphome/core"]
@@ -632,6 +634,13 @@ async def new_binary_sensor(config, *args):
    return var


+def sub_binary_sensors(
+    config: ConfigType, *, parent: MockObj | ID | None = None
+) -> SubEntities:
+    """Return a SubEntities bound to new_binary_sensor."""
+    return SubEntities(new_binary_sensor, config, parent)
+
+
 BINARY_SENSOR_CONDITION_SCHEMA = maybe_simple_id(
    {
        cv.Required(CONF_ID): cv.use_id(BinarySensor),
@@ -150,15 +150,10 @@ async def to_code(config: ConfigType) -> None:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)
-    if frequency_config := config.get(CONF_FREQUENCY):
-        sens = await sensor.new_sensor(frequency_config)
-        cg.add(var.set_frequency_sensor(sens))
-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_FREQUENCY, var.set_frequency_sensor)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)

    for i in range(6):
        if channel_config := config.get(f"{CONF_CHANNEL}_{i + 1}"):
@@ -172,10 +167,5 @@ async def to_code(config: ConfigType) -> None:
                sens = await sensor.new_sensor(energy_config)
                cg.add(getattr(var, f"set_energy_{i + 1}_sensor")(sens))

-    if total_power_config := config.get(CONF_TOTAL_POWER):
-        sens = await sensor.new_sensor(total_power_config)
-        cg.add(var.set_total_power_sensor(sens))
-
-    if total_energy_config := config.get(CONF_TOTAL_ENERGY):
-        sens = await sensor.new_sensor(total_energy_config)
-        cg.add(var.set_total_energy_sensor(sens))
+    await sensors(CONF_TOTAL_POWER, var.set_total_power_sensor)
+    await sensors(CONF_TOTAL_ENERGY, var.set_total_energy_sensor)
@@ -94,27 +94,12 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_1_config := config.get(CONF_CURRENT_1):
-        sens = await sensor.new_sensor(current_1_config)
-        cg.add(var.set_current_sensor_1(sens))
-    if current_2_config := config.get(CONF_CURRENT_2):
-        sens = await sensor.new_sensor(current_2_config)
-        cg.add(var.set_current_sensor_2(sens))
-    if active_power_1_config := config.get(CONF_ACTIVE_POWER_1):
-        sens = await sensor.new_sensor(active_power_1_config)
-        cg.add(var.set_power_sensor_1(sens))
-    if active_power_2_config := config.get(CONF_ACTIVE_POWER_2):
-        sens = await sensor.new_sensor(active_power_2_config)
-        cg.add(var.set_power_sensor_2(sens))
-    if energy_1_config := config.get(CONF_ENERGY_1):
-        sens = await sensor.new_sensor(energy_1_config)
-        cg.add(var.set_energy_sensor_1(sens))
-    if energy_2_config := config.get(CONF_ENERGY_2):
-        sens = await sensor.new_sensor(energy_2_config)
-        cg.add(var.set_energy_sensor_2(sens))
-    if energy_total_config := config.get(CONF_ENERGY_TOTAL):
-        sens = await sensor.new_sensor(energy_total_config)
-        cg.add(var.set_energy_sensor_sum(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT_1, var.set_current_sensor_1)
+    await sensors(CONF_CURRENT_2, var.set_current_sensor_2)
+    await sensors(CONF_ACTIVE_POWER_1, var.set_power_sensor_1)
+    await sensors(CONF_ACTIVE_POWER_2, var.set_power_sensor_2)
+    await sensors(CONF_ENERGY_1, var.set_energy_sensor_1)
+    await sensors(CONF_ENERGY_2, var.set_energy_sensor_2)
+    await sensors(CONF_ENERGY_TOTAL, var.set_energy_sensor_sum)
@@ -231,24 +231,13 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
-    if energy_config := config.get(CONF_ENERGY):
-        sens = await sensor.new_sensor(energy_config)
-        cg.add(var.set_energy_sensor(sens))
-    if internal_temperature_config := config.get(CONF_INTERNAL_TEMPERATURE):
-        sens = await sensor.new_sensor(internal_temperature_config)
-        cg.add(var.set_internal_temperature_sensor(sens))
-    if external_temperature_config := config.get(CONF_EXTERNAL_TEMPERATURE):
-        sens = await sensor.new_sensor(external_temperature_config)
-        cg.add(var.set_external_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)
+    await sensors(CONF_ENERGY, var.set_energy_sensor)
+    await sensors(CONF_INTERNAL_TEMPERATURE, var.set_internal_temperature_sensor)
+    await sensors(CONF_EXTERNAL_TEMPERATURE, var.set_external_temperature_sensor)

    # enable legacy mode
    cg.add(var.set_legacy_mode(config.get(CONF_LEGACY_MODE)))
@@ -101,21 +101,12 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
-    if energy_config := config.get(CONF_ENERGY):
-        sens = await sensor.new_sensor(energy_config)
-        cg.add(var.set_energy_sensor(sens))
-    if frequency_config := config.get(CONF_FREQUENCY):
-        sens = await sensor.new_sensor(frequency_config)
-        cg.add(var.set_frequency_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)
+    await sensors(CONF_ENERGY, var.set_energy_sensor)
+    await sensors(CONF_FREQUENCY, var.set_frequency_sensor)
    cg.add(var.set_line_freq(config[CONF_LINE_FREQUENCY]))
    cg.add(var.set_address(config[CONF_ADDRESS]))
    cg.add(var.set_reset(config[CONF_RESET]))
@@ -7,6 +7,7 @@ from esphome.components.uart import (
    uart_ns,
 )
 from esphome.components.zephyr import zephyr_add_prj_conf
+from esphome.components.zephyr_ble_server import request_ble_l2cap_mtu
 import esphome.config_validation as cv
 from esphome.const import (
    CONF_DEBUG,
@@ -61,6 +62,8 @@ CONFIG_SCHEMA = cv.All(
 async def to_code(config: ConfigType) -> None:
    var = cg.new_Pvariable(config[CONF_ID])
    zephyr_add_prj_conf("BT_NUS", True)
+    zephyr_add_prj_conf("RING_BUFFER", True)
+    request_ble_l2cap_mtu(247)  # DLE sweet spot: one NUS frame per LL PDU
    expose_log = config[CONF_TYPE] == CONF_LOGS
    cg.add(var.set_expose_log(expose_log))
    if expose_log:
@@ -17,6 +17,13 @@
 #include "esphome/core/log.h"

 #include <cstring>
+#include <esp_idf_version.h>
+
+// cancel_open exists from ESP-IDF 5.5.5 and 6.0.1.
+#if (ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 5, 5) && ESP_IDF_VERSION < ESP_IDF_VERSION_VAL(6, 0, 0)) || \
+    ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(6, 0, 1)
+#define BLUEDROID_HAS_CANCEL_OPEN
+#endif

 namespace esphome::bluetooth_connection {

@@ -63,6 +70,12 @@ void BluedroidGattClient::loop() {
    // The one teardown safety net: a lost CLOSE_EVT, or a scheduled
    // teardown whose OPEN_EVT never arrives.
    if (millis() - this->disconnecting_started_ > ble_device_base::GATT_DISCONNECT_TIMEOUT_MS) {
+      if (this->conn_id_ == UNSET_CONN_ID) {
+        this->cancel_pending_open_();
+      } else if (st == ClientState::CONNECTING) {
+        // CONNECT_EVT came but OPEN_EVT was lost, so our open still holds the ACL link.
+        this->check_and_log_error_("esp_ble_gap_disconnect", esp_ble_gap_disconnect(this->remote_bda_));
+      }
      ESP_LOGE(TAG, "[%d] Timeout waiting for teardown, forcing IDLE", this->connection_index_);
      // Release before idling: a lost completion must not leak the cache.
      this->release_services();
@@ -140,6 +153,8 @@ void BluedroidGattClient::tracker_connect_() {
  this->services_released_ = false;
  this->seen_mtu_ = false;
  this->mtu_failed_ = false;
+  this->cancel_open_sent_ = false;
+  this->conn_id_ = UNSET_CONN_ID;
  this->enable_loop();
  this->set_state(ClientState::CONNECTING);
  if (this->connection_type_ == ConnectionType::V3_WITHOUT_CACHE) {
@@ -183,12 +198,28 @@ int BluedroidGattClient::gatt_disconnect() {
    // Arm the safety window: a lost OPEN_EVT must not leak the teardown.
    this->disconnecting_started_ = millis();
    this->enable_loop();
+    if (this->conn_id_ == UNSET_CONN_ID) {
+      // CANCEL_OPEN_EVT or a racing OPEN_EVT settles the slot.
+      this->cancel_pending_open_();
+    }
    return 0;
  }
  this->unconditional_disconnect_();
  return 0;
 }

+void BluedroidGattClient::cancel_pending_open_() {
+#ifdef BLUEDROID_HAS_CANCEL_OPEN
+  esp_ble_gattc_cancel_open_params_t params{};
+  params.gattc_if = this->gattc_if_;
+  memcpy(params.remote_bda, this->remote_bda_, sizeof(esp_bd_addr_t));
+  // A refused cancel schedules no CANCEL_OPEN_EVT, so the teardown stays cancellable.
+  if (this->check_and_log_error_("esp_ble_gattc_cancel_open", esp_ble_gattc_cancel_open(&params)) == ESP_OK) {
+    this->cancel_open_sent_ = true;
+  }
+#endif
+}
+
 void BluedroidGattClient::unconditional_disconnect_() {
  ESP_LOGI(TAG, "[%d] Disconnecting (conn_id: %d)", this->connection_index_, this->conn_id_);
  if (this->conn_id_ == UNSET_CONN_ID) {
@@ -214,6 +245,10 @@ bool BluedroidGattClient::cancel_gatt_disconnect() {
  if (this->state() != ClientState::CONNECTING || !this->disconnect_pending()) {
    return false;
  }
+  if (this->cancel_open_sent_) {
+    // The cancel already went out, so CANCEL_OPEN_EVT ends it.
+    return false;
+  }
  this->want_disconnect_ = false;
  return true;
 }
@@ -574,6 +609,8 @@ void BluedroidGattClient::handle_open_evt_(esp_ble_gattc_cb_param_t *param) {
    this->listener_->on_connection_state(false, 0, param->open.status);
    return;
  }
+  // ALREADY_OPEN on an existing link sends no CONNECT_EVT, so take the id here.
+  this->conn_id_ = param->open.conn_id;
  if (this->disconnect_pending()) {
    // Open resolved with a teardown scheduled: close now (conn_id_ stays set
    // so CLOSE_EVT still matches).
@@ -617,6 +654,11 @@ void BluedroidGattClient::handle_disconnect_evt_(esp_ble_gattc_cb_param_t *param
    // Active close delivers CLOSE_EVT first; never walk back to DISCONNECTING.
    return;
  }
+  if (this->conn_id_ == UNSET_CONN_ID) {
+    // No CONNECT_EVT for this attempt yet, so the event belongs to an earlier
+    // link, such as one the teardown timeout forced down.
+    return;
+  }
  // Passive disconnect: wait for CLOSE_EVT before going IDLE (reconnecting
  // earlier makes the controller reject with 133 or assert) and before
  // reporting - the wrapper frees the slot on the report, and a freed slot
@@ -645,6 +687,10 @@ bool BluedroidGattClient::gattc_event_handler(esp_gattc_cb_event_t event, esp_ga
    case ESP_GATTC_CONNECT_EVT: {
      if (!this->check_addr_(param->connect.remote_bda))
        return false;
+      // Every client interface gets CONNECT_EVT for every new link; only an
+      // attempt in flight owns it. An idle slot must not adopt another slot's link.
+      if (this->state() != ClientState::CONNECTING)
+        break;
      this->conn_id_ = param->connect.conn_id;
      // MTU request here rather than OPEN_EVT, matching the IDF examples.
      auto ret = esp_ble_gattc_send_mtu_req(this->gattc_if_, param->connect.conn_id);
@@ -656,8 +702,15 @@ bool BluedroidGattClient::gattc_event_handler(esp_gattc_cb_event_t event, esp_ga
      break;
    }
    case ESP_GATTC_OPEN_EVT: {
-      if (!this->check_addr_(param->open.remote_bda))
+      if (!this->check_addr_(param->open.remote_bda)) {
+        // Our interface (filtered above), stale address, so nobody tracks this link.
+        if (param->open.status == ESP_GATT_OK || param->open.status == ESP_GATT_ALREADY_OPEN) {
+          ESP_LOGW(TAG, "[%d] Closing link left by an abandoned open", this->connection_index_);
+          this->check_and_log_error_("esp_ble_gattc_close", esp_ble_gattc_close(this->gattc_if_, param->open.conn_id));
+          return true;
+        }
        return false;
+      }
      this->handle_open_evt_(param);
      break;
    }
@@ -748,6 +801,24 @@ bool BluedroidGattClient::gattc_event_handler(esp_gattc_cb_event_t event, esp_ga
      this->listener_->on_notify_data(param->notify.handle, param->notify.value, param->notify.value_len);
      break;
    }
+#ifdef BLUEDROID_HAS_CANCEL_OPEN
+    case ESP_GATTC_CANCEL_OPEN_EVT: {
+      if (!this->check_addr_(param->cancel_open.remote_bda))
+        return false;
+      if (param->cancel_open.status != ESP_GATT_OK) {
+        // Too late to cancel: OPEN_EVT follows and settles the slot. The latch
+        // stays set because the event cannot be tied to this attempt's cancel.
+        break;
+      }
+      if (this->state() == ClientState::CONNECTING && this->disconnect_pending()) {
+        ESP_LOGD(TAG, "[%d] Pending open cancelled", this->connection_index_);
+        this->release_services();
+        this->set_idle_();
+        this->listener_->on_connection_state(false, 0, ESP_GATT_CONN_CONN_CANCEL);
+      }
+      break;
+    }
+#endif
    default:
      break;
  }
@@ -100,6 +100,7 @@ class BluedroidGattClient final : public esp32_ble_tracker::ESPBTClient, public
  int handle_search_cmpl_(esp_gatt_status_t status);
  void deliver_pending_search_();
  void unconditional_disconnect_();
+  void cancel_pending_open_();
  void set_idle_();
  void set_disconnecting_();
  esp_err_t update_conn_params_(uint16_t min_interval, uint16_t max_interval, uint16_t latency, uint16_t timeout,
@@ -133,6 +134,9 @@ class BluedroidGattClient final : public esp32_ble_tracker::ESPBTClient, public
  bool seen_mtu_ : 1 {false};
  // The MTU request was refused at CONNECT_EVT; OPEN_EVT reports instead.
  bool mtu_failed_ : 1 {false};
+  // esp_ble_gattc_cancel_open() was accepted; CANCEL_OPEN_EVT or OPEN_EVT ends
+  // the attempt, so the scheduled teardown can no longer be cancelled.
+  bool cancel_open_sent_ : 1 {false};
  // Search issued at OPEN_EVT overlaps the MTU exchange; discover_services()
  // completes from it. Reset by set_idle_().
  static_assert(static_cast<uint8_t>(SearchState::REPORT_PENDING) < (1 << 4), "search_state_ bitfield too narrow");
@@ -90,20 +90,14 @@ async def to_code_base(config: ConfigType) -> MockObj:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
-        cg.add(var.set_temperature_oversampling(temperature_config[CONF_OVERSAMPLING]))
-
-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure_sensor(sens))
-        cg.add(var.set_pressure_oversampling(pressure_config[CONF_OVERSAMPLING]))
-
-    if humidity_config := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity_config)
-        cg.add(var.set_humidity_sensor(sens))
-        cg.add(var.set_humidity_oversampling(humidity_config[CONF_OVERSAMPLING]))
+    sensors = sensor.sub_sensors(config)
+    if await sensors(CONF_TEMPERATURE, var.set_temperature_sensor):
+        oversampling = config[CONF_TEMPERATURE][CONF_OVERSAMPLING]
+        cg.add(var.set_temperature_oversampling(oversampling))
+    if await sensors(CONF_PRESSURE, var.set_pressure_sensor):
+        cg.add(var.set_pressure_oversampling(config[CONF_PRESSURE][CONF_OVERSAMPLING]))
+    if await sensors(CONF_HUMIDITY, var.set_humidity_sensor):
+        cg.add(var.set_humidity_oversampling(config[CONF_HUMIDITY][CONF_OVERSAMPLING]))

    cg.add(var.set_iir_filter(config[CONF_IIR_FILTER]))

@@ -131,24 +131,15 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
-        cg.add(var.set_temperature_oversampling(temperature_config[CONF_OVERSAMPLING]))
-
-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure_sensor(sens))
-        cg.add(var.set_pressure_oversampling(pressure_config[CONF_OVERSAMPLING]))
-
-    if humidity_config := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humidity_config)
-        cg.add(var.set_humidity_sensor(sens))
-        cg.add(var.set_humidity_oversampling(humidity_config[CONF_OVERSAMPLING]))
-
-    if gas_resistance_config := config.get(CONF_GAS_RESISTANCE):
-        sens = await sensor.new_sensor(gas_resistance_config)
-        cg.add(var.set_gas_resistance_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    if await sensors(CONF_TEMPERATURE, var.set_temperature_sensor):
+        oversampling = config[CONF_TEMPERATURE][CONF_OVERSAMPLING]
+        cg.add(var.set_temperature_oversampling(oversampling))
+    if await sensors(CONF_PRESSURE, var.set_pressure_sensor):
+        cg.add(var.set_pressure_oversampling(config[CONF_PRESSURE][CONF_OVERSAMPLING]))
+    if await sensors(CONF_HUMIDITY, var.set_humidity_sensor):
+        cg.add(var.set_humidity_oversampling(config[CONF_HUMIDITY][CONF_OVERSAMPLING]))
+    await sensors(CONF_GAS_RESISTANCE, var.set_gas_resistance_sensor)

    cg.add(var.set_iir_filter(IIR_FILTER_OPTIONS[config[CONF_IIR_FILTER]]))

@@ -88,16 +88,11 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    for d in ["x", "y", "z"]:
-        accel_key = f"acceleration_{d}"
-        if accel_key in config:
-            sens = await sensor.new_sensor(config[accel_key])
-            cg.add(getattr(var, f"set_accel_{d}_sensor")(sens))
-        accel_key = f"gyroscope_{d}"
-        if accel_key in config:
-            sens = await sensor.new_sensor(config[accel_key])
-            cg.add(getattr(var, f"set_gyro_{d}_sensor")(sens))
-
-    if CONF_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_TEMPERATURE])
-        cg.add(var.set_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_ACCELERATION_X, var.set_accel_x_sensor)
+    await sensors(CONF_GYROSCOPE_X, var.set_gyro_x_sensor)
+    await sensors(CONF_ACCELERATION_Y, var.set_accel_y_sensor)
+    await sensors(CONF_GYROSCOPE_Y, var.set_gyro_y_sensor)
+    await sensors(CONF_ACCELERATION_Z, var.set_accel_z_sensor)
+    await sensors(CONF_GYROSCOPE_Z, var.set_gyro_z_sensor)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
@@ -48,10 +48,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature(sens))
-
-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature)
+    await sensors(CONF_PRESSURE, var.set_pressure)
@@ -75,14 +75,13 @@ async def to_code_base(config: ConfigType) -> MockObj:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)

-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    if await sensors(CONF_TEMPERATURE, var.set_temperature_sensor):
+        temperature_config = config[CONF_TEMPERATURE]
        cg.add(var.set_temperature_oversampling(temperature_config[CONF_OVERSAMPLING]))

-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure_sensor(sens))
+    if await sensors(CONF_PRESSURE, var.set_pressure_sensor):
+        pressure_config = config[CONF_PRESSURE]
        cg.add(var.set_pressure_oversampling(pressure_config[CONF_OVERSAMPLING]))

    cg.add(var.set_iir_filter(config[CONF_IIR_FILTER]))
@@ -80,18 +80,17 @@ async def to_code_base(config: ConfigType) -> MockObj:
    await cg.register_component(var, config)

    cg.add(var.set_iir_filter_config(config[CONF_IIR_FILTER]))
-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    if await sensors(CONF_TEMPERATURE, var.set_temperature_sensor):
+        temperature_config = config[CONF_TEMPERATURE]
        cg.add(
            var.set_temperature_oversampling_config(
                temperature_config[CONF_OVERSAMPLING]
            )
        )

-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure_sensor(sens))
+    if await sensors(CONF_PRESSURE, var.set_pressure_sensor):
+        pressure_config = config[CONF_PRESSURE]
        cg.add(var.set_pressure_oversampling_config(pressure_config[CONF_OVERSAMPLING]))

    return var
@@ -137,9 +137,9 @@ CONFIG_SCHEMA_BASE = cv.Schema(
 async def to_code_base(config: ConfigType) -> MockObj:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)
-    if temperature_config := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature_config)
-        cg.add(var.set_temperature_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    if await sensors(CONF_TEMPERATURE, var.set_temperature_sensor):
+        temperature_config = config[CONF_TEMPERATURE]
        cg.add(
            var.set_temperature_oversampling_config(
                temperature_config[CONF_OVERSAMPLING]
@@ -149,9 +149,8 @@ async def to_code_base(config: ConfigType) -> MockObj:
            var.set_temperature_iir_filter_config(temperature_config[CONF_IIR_FILTER])
        )

-    if pressure_config := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure_config)
-        cg.add(var.set_pressure_sensor(sens))
+    if await sensors(CONF_PRESSURE, var.set_pressure_sensor):
+        pressure_config = config[CONF_PRESSURE]
        cg.add(var.set_pressure_oversampling_config(pressure_config[CONF_OVERSAMPLING]))
        cg.add(var.set_pressure_iir_filter_config(pressure_config[CONF_IIR_FILTER]))

@@ -422,6 +422,21 @@ bool BTHomeMiThermometer::handle_service_data_(const ble_device_base::ServiceDat
        }
        break;
      }
+      case 0x45: {  // temperature (0.1C), e.g. Shelly BLU H&T
+        if (this->temperature_ != nullptr) {
+          const int16_t raw = encode_uint16(value[1], value[0]);
+          this->temperature_->publish_state(raw * 0.1f);
+          reported = true;
+        }
+        break;
+      }
+      case 0x2E: {  // humidity (uint8, 1%), e.g. Shelly BLU H&T
+        if (this->humidity_ != nullptr) {
+          this->humidity_->publish_state(value[0]);
+          reported = true;
+        }
+        break;
+      }
      default:
        break;
    }
@@ -72,18 +72,9 @@ async def to_code(config: ConfigType) -> None:
    var = cg.new_Pvariable(config[CONF_ID])
    await setup_bthome_mithermometer(var, config)

-    if temp_sens := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temp_sens)
-        cg.add(var.set_temperature(sens))
-    if humi_sens := config.get(CONF_HUMIDITY):
-        sens = await sensor.new_sensor(humi_sens)
-        cg.add(var.set_humidity(sens))
-    if batl_sens := config.get(CONF_BATTERY_LEVEL):
-        sens = await sensor.new_sensor(batl_sens)
-        cg.add(var.set_battery_level(sens))
-    if batv_sens := config.get(CONF_BATTERY_VOLTAGE):
-        sens = await sensor.new_sensor(batv_sens)
-        cg.add(var.set_battery_voltage(sens))
-    if sgnl_sens := config.get(CONF_SIGNAL_STRENGTH):
-        sens = await sensor.new_sensor(sgnl_sens)
-        cg.add(var.set_signal_strength(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature)
+    await sensors(CONF_HUMIDITY, var.set_humidity)
+    await sensors(CONF_BATTERY_LEVEL, var.set_battery_level)
+    await sensors(CONF_BATTERY_VOLTAGE, var.set_battery_voltage)
+    await sensors(CONF_SIGNAL_STRENGTH, var.set_signal_strength)
@@ -16,8 +16,9 @@ from esphome.const import (
    DEVICE_CLASS_RESTART,
    DEVICE_CLASS_UPDATE,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
 from esphome.core.entity_helpers import (
+    SubEntities,
    entity_duplicate_validator,
    queue_entity_register,
    setup_device_class,
@@ -114,6 +115,13 @@ async def new_button(config: ConfigType, *args: SafeExpType) -> MockObj:
    return var


+def sub_buttons(
+    config: ConfigType, *, parent: MockObj | ID | None = None
+) -> SubEntities:
+    """Return a SubEntities bound to new_button."""
+    return SubEntities(new_button, config, parent)
+
+
 BUTTON_PRESS_SCHEMA = maybe_simple_id(
    {
        cv.Required(CONF_ID): cv.use_id(Button),
@@ -65,17 +65,12 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if eco2_config := config.get(CONF_ECO2):
-        sens = await sensor.new_sensor(eco2_config)
-        cg.add(var.set_co2(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_ECO2, var.set_co2)
+    await sensors(CONF_TVOC, var.set_tvoc)

-    if tvoc_config := config.get(CONF_TVOC):
-        sens = await sensor.new_sensor(tvoc_config)
-        cg.add(var.set_tvoc(sens))
-
-    if version_config := config.get(CONF_VERSION):
-        sens = await text_sensor.new_text_sensor(version_config)
-        cg.add(var.set_version(sens))
+    text_sensors = text_sensor.sub_text_sensors(config)
+    await text_sensors(CONF_VERSION, var.set_version)

    if (baseline := config.get(CONF_BASELINE)) is not None:
        cg.add(var.set_baseline(baseline))
@@ -368,19 +368,11 @@ optional<ClimateDeviceRestoreState> Climate::restore_state_() {
 }

 void Climate::save_state_(const ClimateTraits &traits) {
-#if (defined(USE_ESP32) || defined(USE_ESP8266)) && !defined(CLANG_TIDY)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wclass-memaccess"
-#define TEMP_IGNORE_MEMACCESS
-#endif
  ClimateDeviceRestoreState state{};
-  // initialize as zero (including padding) to prevent random data on stack triggering erase
+  // initialize as zero (including padding) to prevent random data on stack triggering erase;
+  // the void * cast tells GCC the bytewise clear of a non-trivial type is intentional
  // 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
-#undef TEMP_IGNORE_MEMACCESS
-#endif
+  memset(static_cast<void *>(&state), 0, sizeof(ClimateDeviceRestoreState));

  state.mode = this->mode;
  if (traits.has_feature_flags(CLIMATE_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE |
@@ -54,9 +54,8 @@ async def to_code(config: ConfigType) -> None:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)
-    if co2_config := config.get(CONF_CO2):
-        sens = await sensor.new_sensor(co2_config)
-        cg.add(var.set_co2_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_CO2, var.set_co2_sensor)


 CALIBRATION_ACTION_SCHEMA = maybe_simple_id(
@@ -203,6 +203,5 @@ async def to_code(config: ConfigType) -> None:
        else:
            cg.add(var.add_source(source))

-    if CONF_STD_DEV in config:
-        sens = await sensor.new_sensor(config[CONF_STD_DEV])
-        cg.add(var.set_std_dev_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_STD_DEV, var.set_std_dev_sensor)
@@ -7,6 +7,7 @@ BYTE_ORDER_BIG = "big_endian"

 CONF_ACCELEROMETER_ODR = "accelerometer_odr"
 CONF_ACCELEROMETER_RANGE = "accelerometer_range"
+CONF_ALLOWED_IPS = "allowed_ips"
 CONF_B_CONSTANT = "b_constant"
 CONF_BREATH_VOC_EQUIVALENT = "breath_voc_equivalent"
 CONF_BYTE_ORDER = "byte_order"
@@ -15,6 +16,8 @@ CONF_CLIMATE_ID = "climate_id"
 CONF_CO2_EQUIVALENT = "co2_equivalent"
 CONF_COLOR_DEPTH = "color_depth"
 CONF_COLUMNS = "columns"
+CONF_CONNECTED = "connected"
+CONF_CONVERSION_RATE = "conversion_rate"
 CONF_CRC_ENABLE = "crc_enable"
 CONF_DATA_BITS = "data_bits"
 CONF_DESCRIPTION = "description"
@@ -40,7 +43,9 @@ CONF_ON_SCAN_END = "on_scan_end"
 CONF_ON_STATE_CHANGE = "on_state_change"
 CONF_PARITY = "parity"
 CONF_RECEIVER_FREQUENCY = "receiver_frequency"
+CONF_RECONNECT_INTERVAL = "reconnect_interval"
 CONF_REQUEST_HEADERS = "request_headers"
+CONF_ROLE = "role"
 CONF_ROWS = "rows"
 CONF_SCAN_PARAMETERS = "scan_parameters"
 CONF_SHA256 = "sha256"
@@ -0,0 +1 @@
+CODEOWNERS = ["@clydebarrow"]
@@ -0,0 +1,28 @@
+#include "counter_sensor.h"
+#include "esphome/core/log.h"
+
+namespace esphome::counter {
+
+static const char *const TAG = "counter";
+
+void CounterSensor::setup() {
+  if (this->restore_) {
+    this->pref_ = this->make_entity_preference<int64_t>();
+    this->pref_.load(&this->value_);
+  }
+  this->publish_state(static_cast<float>(this->value_));
+}
+
+void CounterSensor::set_value(int64_t value) {
+  this->value_ = value;
+  this->publish_state(static_cast<float>(value));
+  if (this->restore_)
+    this->pref_.save(&this->value_);
+}
+
+void CounterSensor::dump_config() {
+  LOG_SENSOR("", "Counter", this);
+  ESP_LOGCONFIG(TAG, "  Restore: %s", YESNO(this->restore_));
+}
+
+}  // namespace esphome::counter
@@ -0,0 +1,47 @@
+#pragma once
+
+#include <cstdint>
+
+#include "esphome/core/component.h"
+#include "esphome/core/preferences.h"
+#include "esphome/components/sensor/sensor.h"
+
+namespace esphome::counter {
+
+/// A counter held as a 64-bit integer. The published sensor state is a float, so it is exact only up to 2^24.
+class CounterSensor final : public sensor::Sensor, public Component {
+ public:
+  /// The counter starts at initial_value unless a stored value is restored.
+  CounterSensor(bool restore, int64_t initial_value) : value_(initial_value), restore_(restore) {}
+
+  void setup() override;
+  void dump_config() override;
+  // restore value before `on_boot` automations run
+  float get_setup_priority() const override { return setup_priority::DATA + 50.0f; }
+
+  /// Increment by one each time the given sensor publishes a state.
+  void count_updates_from(sensor::Sensor *source) {
+    source->add_on_state_callback([this](float) { this->increment(); });
+  }
+
+  /// Increment by one each time the given binary sensor changes to true.
+  template<typename T> void count_true_from(T *source) {
+    source->add_on_state_callback([this](bool state) {
+      if (state)
+        this->increment();
+    });
+  }
+
+  void set_value(int64_t value);
+  /// overflow on addition of signed numbers is undefined - use the well defined unsigned version
+  void increment(int64_t amount = 1) {
+    this->set_value(static_cast<int64_t>(static_cast<uint64_t>(this->value_) + static_cast<uint64_t>(amount)));
+  }
+
+ protected:
+  ESPPreferenceObject pref_;
+  int64_t value_;
+  bool restore_;
+};
+
+}  // namespace esphome::counter
@@ -0,0 +1,85 @@
+from esphome import automation
+import esphome.codegen as cg
+from esphome.components import binary_sensor, sensor
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_BINARY_SENSOR,
+    CONF_ID,
+    CONF_INITIAL_VALUE,
+    CONF_RESTORE,
+    CONF_SENSOR,
+    CONF_VALUE,
+    ICON_COUNTER,
+)
+from esphome.types import ConfigType
+
+counter_ns = cg.esphome_ns.namespace("counter")
+CounterSensor = counter_ns.class_("CounterSensor", sensor.Sensor, cg.Component)
+
+# The lowest value is left out because its C++ literal cannot be written portably.
+INT64_MAX = 2**63 - 1
+COUNTER_RANGE = cv.int_range(min=-INT64_MAX, max=INT64_MAX)
+COUNTER_VALUE = cv.templatable(COUNTER_RANGE)
+
+
+def _not_own_source(config: ConfigType) -> ConfigType:
+    if (source := config.get(CONF_SENSOR)) is not None and source.id == config[
+        CONF_ID
+    ].id:
+        raise cv.Invalid("A counter cannot count its own updates", [CONF_SENSOR])
+    return config
+
+
+CONFIG_SCHEMA = cv.All(
+    sensor.sensor_schema(
+        CounterSensor,
+        icon=ICON_COUNTER,
+        accuracy_decimals=0,
+    )
+    .extend(
+        {
+            cv.Optional(CONF_RESTORE, default=True): cv.boolean,
+            cv.Optional(CONF_INITIAL_VALUE, default=0): COUNTER_RANGE,
+            cv.Optional(CONF_SENSOR): cv.use_id(sensor.Sensor),
+            cv.Optional(CONF_BINARY_SENSOR): cv.use_id(binary_sensor.BinarySensor),
+        }
+    )
+    .extend(cv.COMPONENT_SCHEMA),
+    _not_own_source,
+)
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(
+        config[CONF_ID], config[CONF_RESTORE], config[CONF_INITIAL_VALUE]
+    )
+    await cg.register_component(var, config)
+    await sensor.register_sensor(var, config)
+    if (source := config.get(CONF_SENSOR)) is not None:
+        cg.add(var.count_updates_from(await cg.get_variable(source)))
+    if (source := config.get(CONF_BINARY_SENSOR)) is not None:
+        cg.add(var.count_true_from(await cg.get_variable(source)))
+
+
+automation.register_apply_action(
+    "counter.set_value",
+    cv.maybe_simple_value(
+        {
+            cv.GenerateID(CONF_ID): cv.use_id(CounterSensor),
+            cv.Required(CONF_VALUE): COUNTER_VALUE,
+        },
+        key=CONF_VALUE,
+    ),
+    automation.ApplyField(CONF_VALUE, "set_value", cg.int64),
+)
+
+automation.register_apply_action(
+    "counter.increment",
+    automation.maybe_simple_id(
+        {
+            cv.GenerateID(CONF_ID): cv.use_id(CounterSensor),
+            cv.Optional(CONF_VALUE, default=1): COUNTER_VALUE,
+        }
+    ),
+    automation.ApplyField(CONF_VALUE, "increment", cg.int64),
+)
@@ -117,15 +117,10 @@ async def to_code(config: ConfigType) -> None:
    cg.add(var.set_hpf_enable(config[CONF_CURRENT_HPF], config[CONF_VOLTAGE_HPF]))
    cg.add(var.set_pulse_energy_wh(config[CONF_PULSE_ENERGY]))

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)


 automation.register_apply_action(
@@ -98,24 +98,11 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await uart.register_uart_device(var, config)

-    if voltage_config := config.get(CONF_VOLTAGE):
-        sens = await sensor.new_sensor(voltage_config)
-        cg.add(var.set_voltage_sensor(sens))
-    if current_config := config.get(CONF_CURRENT):
-        sens = await sensor.new_sensor(current_config)
-        cg.add(var.set_current_sensor(sens))
-    if power_config := config.get(CONF_POWER):
-        sens = await sensor.new_sensor(power_config)
-        cg.add(var.set_power_sensor(sens))
-    if energy_config := config.get(CONF_ENERGY):
-        sens = await sensor.new_sensor(energy_config)
-        cg.add(var.set_energy_sensor(sens))
-    if apparent_power_config := config.get(CONF_APPARENT_POWER):
-        sens = await sensor.new_sensor(apparent_power_config)
-        cg.add(var.set_apparent_power_sensor(sens))
-    if reactive_power_config := config.get(CONF_REACTIVE_POWER):
-        sens = await sensor.new_sensor(reactive_power_config)
-        cg.add(var.set_reactive_power_sensor(sens))
-    if power_factor_config := config.get(CONF_POWER_FACTOR):
-        sens = await sensor.new_sensor(power_factor_config)
-        cg.add(var.set_power_factor_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_VOLTAGE, var.set_voltage_sensor)
+    await sensors(CONF_CURRENT, var.set_current_sensor)
+    await sensors(CONF_POWER, var.set_power_sensor)
+    await sensors(CONF_ENERGY, var.set_energy_sensor)
+    await sensors(CONF_APPARENT_POWER, var.set_apparent_power_sensor)
+    await sensors(CONF_REACTIVE_POWER, var.set_reactive_power_sensor)
+    await sensors(CONF_POWER_FACTOR, var.set_power_factor_sensor)
@@ -1,4 +1,5 @@
 import esphome.codegen as cg
+from esphome.components.nrf52.framework import include_west_project
 from esphome.components.zephyr import zephyr_add_prj_conf
 from esphome.config_helpers import filter_source_files_from_platform
 import esphome.config_validation as cv
@@ -51,13 +52,15 @@ async def to_code(config: ConfigType) -> None:
        zephyr_add_prj_conf("HWINFO", True)
        # gdb thread support
        zephyr_add_prj_conf("DEBUG_THREAD_INFO", True)
-        # RTT
+        # RTT sources live in the segger project
+        include_west_project("segger")
        zephyr_add_prj_conf("USE_SEGGER_RTT", True)
        zephyr_add_prj_conf("RTT_CONSOLE", True)
        zephyr_add_prj_conf("LOG", True)
        zephyr_add_prj_conf("LOG_BLOCK_IN_THREAD", True)
        zephyr_add_prj_conf("LOG_BUFFER_SIZE", 4096)
        zephyr_add_prj_conf("SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL", True)
+        zephyr_add_prj_conf("PRINTK", True)
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)
    cg.add_define("USE_DEBUG")
@@ -106,32 +106,13 @@ CONFIG_SCHEMA = {


 async def to_code(config: ConfigType) -> None:
-    debug_component = await cg.get_variable(config[CONF_DEBUG_ID])
+    hub = await cg.get_variable(config[CONF_DEBUG_ID])

-    if free_conf := config.get(CONF_FREE):
-        sens = await sensor.new_sensor(free_conf)
-        cg.add(debug_component.set_free_sensor(sens))
-
-    if block_conf := config.get(CONF_BLOCK):
-        sens = await sensor.new_sensor(block_conf)
-        cg.add(debug_component.set_block_sensor(sens))
-
-    if fragmentation_conf := config.get(CONF_FRAGMENTATION):
-        sens = await sensor.new_sensor(fragmentation_conf)
-        cg.add(debug_component.set_fragmentation_sensor(sens))
-
-    if min_free_conf := config.get(CONF_MIN_FREE):
-        sens = await sensor.new_sensor(min_free_conf)
-        cg.add(debug_component.set_min_free_sensor(sens))
-
-    if loop_time_conf := config.get(CONF_LOOP_TIME):
-        sens = await sensor.new_sensor(loop_time_conf)
-        cg.add(debug_component.set_loop_time_sensor(sens))
-
-    if psram_conf := config.get(CONF_PSRAM):
-        sens = await sensor.new_sensor(psram_conf)
-        cg.add(debug_component.set_psram_sensor(sens))
-
-    if cpu_freq_conf := config.get(CONF_CPU_FREQUENCY):
-        sens = await sensor.new_sensor(cpu_freq_conf)
-        cg.add(debug_component.set_cpu_frequency_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_FREE, hub.set_free_sensor)
+    await sensors(CONF_BLOCK, hub.set_block_sensor)
+    await sensors(CONF_FRAGMENTATION, hub.set_fragmentation_sensor)
+    await sensors(CONF_MIN_FREE, hub.set_min_free_sensor)
+    await sensors(CONF_LOOP_TIME, hub.set_loop_time_sensor)
+    await sensors(CONF_PSRAM, hub.set_psram_sensor)
+    await sensors(CONF_CPU_FREQUENCY, hub.set_cpu_frequency_sensor)
@@ -31,11 +31,8 @@ CONFIG_SCHEMA = cv.Schema(


 async def to_code(config: ConfigType) -> None:
-    debug_component = await cg.get_variable(config[CONF_DEBUG_ID])
+    hub = await cg.get_variable(config[CONF_DEBUG_ID])

-    if CONF_DEVICE in config:
-        sens = await text_sensor.new_text_sensor(config[CONF_DEVICE])
-        cg.add(debug_component.set_device_info_sensor(sens))
-    if CONF_RESET_REASON in config:
-        sens = await text_sensor.new_text_sensor(config[CONF_RESET_REASON])
-        cg.add(debug_component.set_reset_reason_sensor(sens))
+    text_sensors = text_sensor.sub_text_sensors(config)
+    await text_sensors(CONF_DEVICE, hub.set_device_info_sensor)
+    await text_sensors(CONF_RESET_REASON, hub.set_reset_reason_sensor)
@@ -187,19 +187,18 @@ async def dfrobot_sen0395_settings_to_code(
            template_ = await cg.templatable(segments[7], args, cg.float_)
            cg.add(var.set_det_max4(template_))
    if CONF_OUTPUT_LATENCY in config:
-        template_ = await cg.templatable(
-            config[CONF_OUTPUT_LATENCY][CONF_DELAY_AFTER_DETECT], args, float
-        )
-        if isinstance(template_, cv.TimePeriod):
-            template_ = template_.total_milliseconds / 1000
-        cg.add(var.set_delay_after_detect(template_))
-
-        template_ = await cg.templatable(
-            config[CONF_OUTPUT_LATENCY][CONF_DELAY_AFTER_DISAPPEAR], args, float
-        )
-        if isinstance(template_, cv.TimePeriod):
-            template_ = template_.total_milliseconds / 1000
-        cg.add(var.set_delay_after_disappear(template_))
+        latency = config[CONF_OUTPUT_LATENCY]
+        for key, setter in (
+            (CONF_DELAY_AFTER_DETECT, var.set_delay_after_detect),
+            (CONF_DELAY_AFTER_DISAPPEAR, var.set_delay_after_disappear),
+        ):
+            template_ = await cg.templatable(
+                latency[key],
+                args,
+                float,
+                to_exp=lambda period: period.total_milliseconds / 1000,
+            )
+            cg.add(setter(template_))
    if CONF_SENSITIVITY in config:
        template_ = await cg.templatable(config[CONF_SENSITIVITY], args, cg.int8)
        cg.add(var.set_sensitivity(template_))
@@ -61,11 +61,8 @@ async def to_code(config: ConfigType) -> None:
    pin = await gpio_pin_expression(config[CONF_PIN])
    cg.add(var.set_pin(pin))

-    if CONF_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_TEMPERATURE])
-        cg.add(var.set_temperature_sensor(sens))
-    if CONF_HUMIDITY in config:
-        sens = await sensor.new_sensor(config[CONF_HUMIDITY])
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)

    cg.add(var.set_dht_model(config[CONF_MODEL]))
@@ -46,10 +46,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if CONF_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_TEMPERATURE])
-        cg.add(var.set_temperature_sensor(sens))
-
-    if CONF_HUMIDITY in config:
-        sens = await sensor.new_sensor(config[CONF_HUMIDITY])
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
@@ -287,13 +287,15 @@ template<typename T> class DisplayWriter {
 // Type alias for Display writer - uses optimized DisplayWriter instead of std::function
 using display_writer_t = DisplayWriter<Display>;

+// Callers usually pass `this`; checking a copy keeps GCC's -Wnonnull-compare quiet.
 #define LOG_DISPLAY(prefix, type, obj) \
-  if ((obj) != nullptr) { \
+  if (auto *log_display_obj = (obj); log_display_obj != nullptr) { \
    ESP_LOGCONFIG(TAG, \
                  prefix type "\n" \
                              "%s  Rotations: %d °\n" \
                              "%s  Dimensions: %dpx x %dpx", \
-                  prefix, (obj)->rotation_, prefix, (obj)->get_width(), (obj)->get_height()); \
+                  prefix, log_display_obj->rotation_, prefix, log_display_obj->get_width(), \
+                  log_display_obj->get_height()); \
  }

 /// Turn the pixel OFF.
@@ -86,7 +86,7 @@ void DlmsMeterComponent::setup() { this->flush_rx_buffer_(); }

 void DlmsMeterComponent::dump_config() {
  ESP_LOGCONFIG(TAG, "DLMS Meter:");
-  ESP_LOGCONFIG(TAG, "  Receive Timeout: %u ms", this->receive_timeout_ms_);
+  ESP_LOGCONFIG(TAG, "  Receive Timeout: %" PRIu32 " ms", this->receive_timeout_ms_);
  ESP_LOGCONFIG(TAG, "  Skip CRC Check: %s", YESNO(this->skip_crc_check_));

  for (const auto &pattern : this->custom_patterns_) {
@@ -54,10 +54,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature)
-        cg.add(var.set_temperature_sensor(sens))
-
-    if pressure := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure)
-        cg.add(var.set_pressure_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_PRESSURE, var.set_pressure_sensor)
@@ -63,9 +63,8 @@ async def to_code(config: ConfigType) -> None:
    if CONF_LAMBDA in config:
        lambda_ = await cg.process_lambda(config[CONF_LAMBDA], [], return_type=cg.bool_)
        cg.add(var.set_lambda(lambda_))
-    if CONF_LAST_TIME in config:
-        sens = await sensor.new_sensor(config[CONF_LAST_TIME])
-        cg.add(var.set_last_duty_time_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_LAST_TIME, var.set_last_duty_time_sensor)


 # AUTOMATIONS
@@ -57,14 +57,7 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if temperature := config.get(CONF_TEMPERATURE):
-        sens = await sensor.new_sensor(temperature)
-        cg.add(var.set_temperature_sensor(sens))
-
-    if co2 := config.get(CONF_CO2):
-        sens = await sensor.new_sensor(co2)
-        cg.add(var.set_co2_sensor(sens))
-
-    if pressure := config.get(CONF_PRESSURE):
-        sens = await sensor.new_sensor(pressure)
-        cg.add(var.set_pressure_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_CO2, var.set_co2_sensor)
+    await sensors(CONF_PRESSURE, var.set_pressure_sensor)
@@ -1,5 +1,6 @@
 import esphome.codegen as cg
 from esphome.components import i2c
+from esphome.components.const import CONF_CONVERSION_RATE
 import esphome.config_validation as cv
 from esphome.const import CONF_ID, CONF_INVERTED, CONF_RESOLUTION
 from esphome.types import ConfigType
@@ -13,7 +14,6 @@ MULTI_CONF = True
 CONF_PWM = "pwm"
 CONF_DIVIDER = "divider"
 CONF_DAC = "dac"
-CONF_CONVERSION_RATE = "conversion_rate"

 CONF_EMC2101_ID = "emc2101_id"

@@ -55,22 +55,12 @@ CONFIG_SCHEMA = EMC2101_COMPONENT_SCHEMA.extend(


 async def to_code(config: ConfigType) -> None:
-    paren = await cg.get_variable(config[CONF_EMC2101_ID])
-    var = cg.new_Pvariable(config[CONF_ID], paren)
+    hub = await cg.get_variable(config[CONF_EMC2101_ID])
+    var = cg.new_Pvariable(config[CONF_ID], hub)
    await cg.register_component(var, config)

-    if CONF_INTERNAL_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_INTERNAL_TEMPERATURE])
-        cg.add(var.set_internal_temperature_sensor(sens))
-
-    if CONF_EXTERNAL_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_EXTERNAL_TEMPERATURE])
-        cg.add(var.set_external_temperature_sensor(sens))
-
-    if CONF_SPEED in config:
-        sens = await sensor.new_sensor(config[CONF_SPEED])
-        cg.add(var.set_speed_sensor(sens))
-
-    if CONF_DUTY_CYCLE in config:
-        sens = await sensor.new_sensor(config[CONF_DUTY_CYCLE])
-        cg.add(var.set_duty_cycle_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_INTERNAL_TEMPERATURE, var.set_internal_temperature_sensor)
+    await sensors(CONF_EXTERNAL_TEMPERATURE, var.set_external_temperature_sensor)
+    await sensors(CONF_SPEED, var.set_speed_sensor)
+    await sensors(CONF_DUTY_CYCLE, var.set_duty_cycle_sensor)
@@ -63,15 +63,10 @@ async def to_code_base(config: ConfigType) -> MockObj:
    var = cg.new_Pvariable(config[CONF_ID])
    await cg.register_component(var, config)

-    if eco2_config := config.get(CONF_ECO2):
-        sens = await sensor.new_sensor(eco2_config)
-        cg.add(var.set_co2(sens))
-    if tvoc_config := config.get(CONF_TVOC):
-        sens = await sensor.new_sensor(tvoc_config)
-        cg.add(var.set_tvoc(sens))
-    if aqi_config := config.get(CONF_AQI):
-        sens = await sensor.new_sensor(aqi_config)
-        cg.add(var.set_aqi(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_ECO2, var.set_co2)
+    await sensors(CONF_TVOC, var.set_tvoc)
+    await sensors(CONF_AQI, var.set_aqi)

    if compensation_config := config.get(CONF_COMPENSATION):
        sens = await cg.get_variable(compensation_config[CONF_TEMPERATURE])
@@ -50,10 +50,6 @@ async def to_code(config: ConfigType) -> None:
    await cg.register_component(var, config)
    await i2c.register_i2c_device(var, config)

-    if CONF_TEMPERATURE in config:
-        sens = await sensor.new_sensor(config[CONF_TEMPERATURE])
-        cg.add(var.set_temperature_sensor(sens))
-
-    if CONF_HUMIDITY in config:
-        sens = await sensor.new_sensor(config[CONF_HUMIDITY])
-        cg.add(var.set_humidity_sensor(sens))
+    sensors = sensor.sub_sensors(config)
+    await sensors(CONF_TEMPERATURE, var.set_temperature_sensor)
+    await sensors(CONF_HUMIDITY, var.set_humidity_sensor)
@@ -16,6 +16,28 @@ namespace esphome::epaper_spi {
 /** Delta for when to regard as gray */
 static constexpr uint8_t COLORCONV_GRAY_THRESHOLD = 50;

+/** Rec.601 luma (0.299/0.587/0.114 weights, scaled by 256) for optimum perceptual brightness */
+constexpr uint8_t rec601_luma(Color color) {
+  return (uint8_t) ((77u * color.r + 150u * color.g + 29u * color.b + 128u) >> 8);
+}
+
+/** Map RGB color to a single monochrome bit
+ *
+ * @param color RGB color to convert from
+ * @return      1 = white, 0 = black
+ */
+constexpr uint8_t color_to_mono(Color color) { return rec601_luma(color) >= 128 ? 1 : 0; }
+
+/** Map RGB color to one of 4 discrete gray levels (2 bits per pixel)
+ *
+ * @param color RGB color to convert from
+ * @return      Gray level: 0 = black, 3 = white
+ */
+constexpr uint8_t color_to_gray4(Color color) {
+  const uint8_t level = (uint8_t) ((rec601_luma(color) + 32u) >> 6);  // quantize 0..255 to 0..3, rounded
+  return level > 3 ? 3 : level;
+}
+
 /** Map RGB color to discrete BWYR hex 4 color key
 *
 * @tparam NATIVE_COLOR  Type of native hardware color values
@@ -25,7 +47,6 @@ static constexpr uint8_t COLORCONV_GRAY_THRESHOLD = 50;
 * @param hw_yellow Native value for yellow
 * @param hw_red    Native value for red
 * @return          Converted native hardware color value
- * @internal Constexpr. Does not depend on side effects ("pure").
 */
 template<typename NATIVE_COLOR>
 constexpr NATIVE_COLOR color_to_bwyr(Color color, NATIVE_COLOR hw_black, NATIVE_COLOR hw_white, NATIVE_COLOR hw_yellow,
@@ -38,11 +59,7 @@ constexpr NATIVE_COLOR color_to_bwyr(Color color, NATIVE_COLOR hw_black, NATIVE_

  if ((max_rgb - min_rgb) < COLORCONV_GRAY_THRESHOLD) {
    // It's a shade of gray. Map to BLACK or WHITE.
-    // We split the luminance at the halfway point (382 = (255*3)/2)
-    if ((static_cast<int>(color.r) + color.g + color.b) > 382) {
-      return hw_white;
-    }
-    return hw_black;
+    return color_to_mono(color) ? hw_white : hw_black;
  }

  // --- Step 2: Check for Primary/Secondary Colors ---
@@ -96,7 +113,6 @@ constexpr NATIVE_COLOR color_to_bwr(Color color, NATIVE_COLOR hw_black, NATIVE_C
 * @param hw_green  Native value for green
 * @param hw_blue   Native value for blue
 * @return          Converted native hardware color value
- * @internal Constexpr. Does not depend on side effects ("pure").
 */
 template<typename NATIVE_COLOR>
 constexpr NATIVE_COLOR color_to_bwyrgb(Color color, NATIVE_COLOR hw_black, NATIVE_COLOR hw_white,
@@ -105,10 +121,7 @@ constexpr NATIVE_COLOR color_to_bwyrgb(Color color, NATIVE_COLOR hw_black, NATIV
  const auto [min_rgb, max_rgb] = std::minmax({color.r, color.g, color.b});

  if ((max_rgb - min_rgb) < COLORCONV_GRAY_THRESHOLD) {
-    if ((static_cast<int>(color.r) + color.g + color.b) > 382) {
-      return hw_white;
-    }
-    return hw_black;
+    return color_to_mono(color) ? hw_white : hw_black;
  }

  const bool r_on = (color.r > 128);
@@ -158,7 +171,6 @@ constexpr NATIVE_COLOR color_to_bwyrgb(Color color, NATIVE_COLOR hw_black, NATIV
 * @param hw_blue   Native value for blue
 * @param hw_orange Native value for orange
 * @return          Converted native hardware color value
- * @internal Constexpr. Does not depend on side effects ("pure").
 */
 template<typename NATIVE_COLOR>
 constexpr NATIVE_COLOR color_to_bwyrgbo(Color color, NATIVE_COLOR hw_black, NATIVE_COLOR hw_white,
@@ -167,10 +179,7 @@ constexpr NATIVE_COLOR color_to_bwyrgbo(Color color, NATIVE_COLOR hw_black, NATI
  const auto [min_rgb, max_rgb] = std::minmax({color.r, color.g, color.b});

  if ((max_rgb - min_rgb) < COLORCONV_GRAY_THRESHOLD) {
-    if ((static_cast<int>(color.r) + color.g + color.b) > 382) {
-      return hw_white;
-    }
-    return hw_black;
+    return color_to_mono(color) ? hw_white : hw_black;
  }

  const bool r_on = (color.r > 128);
@@ -1,7 +1,9 @@
+from collections.abc import Callable
 import importlib
 import pkgutil
+from typing import Any

-from esphome import core, pins
+from esphome import automation, core, pins
 import esphome.codegen as cg
 from esphome.components import display, spi
 from esphome.components.display import CONF_SHOW_TEST_CARD, validate_rotation
@@ -54,6 +56,12 @@ EPaperBase = epaper_spi_ns.class_(
 )
 Transform = epaper_spi_ns.enum("Transform")

+automation.register_apply_action(
+    "epaper_spi.full_update_next",
+    automation.maybe_simple_id({cv.Required(CONF_ID): cv.use_id(EPaperBase)}),
+    automation.ApplyCall("request_full_update()"),
+)
+
 # Import all models dynamically from the models package
 for module_info in pkgutil.iter_modules(models.__path__):
    importlib.import_module(f".models.{module_info.name}", package=__package__)
@@ -70,6 +78,23 @@ DIMENSION_SCHEMA = cv.Schema(
 TRANSFORM_OPTIONS = {CONF_MIRROR_X, CONF_MIRROR_Y, CONF_SWAP_XY}


+def _full_update_every_validator(
+    model: models.EpaperModel,
+) -> Callable[[Any], int]:
+    if model.get_default("partial_update"):
+        return cv.int_range(1, 255)
+
+    def validate(value: Any) -> int:
+        value = cv.int_range(1, 255)(value)
+        if value != 1:
+            raise cv.Invalid(
+                f"{model.name} does not support partial update; full_update_every must be 1"
+            )
+        return value
+
+    return validate
+
+
 def model_schema(config):
    model = MODELS[config[CONF_MODEL]]
    class_name = epaper_spi_ns.class_(model.class_name, EPaperBase)
@@ -96,7 +121,9 @@ def model_schema(config):
                    cv.Required(CONF_MIRROR_Y): cv.boolean,
                }
            ),
-            cv.Optional(CONF_FULL_UPDATE_EVERY, default=1): cv.int_range(1, 255),
+            cv.Optional(
+                CONF_FULL_UPDATE_EVERY, default=1
+            ): _full_update_every_validator(model),
            model.option(CONF_BUSY_PIN): pins.gpio_input_pin_schema,
            model.option(CONF_CS_PIN): pins.gpio_output_pin_schema,
            model.option(CONF_DC_PIN, fallback=None): pins.gpio_output_pin_schema,
@@ -132,8 +159,15 @@ def customise_schema(config):
        extra=cv.ALLOW_EXTRA,
    )(config)
    model = MODELS[config[CONF_MODEL]]
+    model.check_requirements()
    config = model_schema(config)(config)
+    config = model.validate_config(config)
    width, height = model.get_dimensions(config)
+    if width % (width_multiple := model.get_default("width_multiple", 1)):
+        raise cv.Invalid(
+            f"{model.name} requires a width that is a multiple of {width_multiple}",
+            path=[CONF_DIMENSIONS],
+        )
    display.add_metadata(
        config[CONF_ID],
        width,
--- a/Show More
+++ b/Show More