Merge pull request #20680 from esphome/bump-2026.10.0b4

2026.10.0b4
Bump version to 2026.10.0b4
2026-10-14 18:22:48 +00:00 · 2026-10-14 11:14:49 +13:00 · 2026-10-14 10:43:50 +13:00 · 2026-10-14 10:43:49 +13:00 · 2026-10-14 10:43:49 +13:00 · 2026-10-14 10:43:49 +13:00
1229 changed files with 53118 additions and 9174 deletions
@@ -22,7 +22,7 @@ runs:
        # cached path cannot diverge.
        echo "ESPHOME_ARDUINO8266_PREFIX=$HOME/.esphome-arduino8266" >> "$GITHUB_ENV"
        . venv/bin/activate
-        key=$(python -c 'from esphome.components.esp8266 import RECOMMENDED_ARDUINO_FRAMEWORK_VERSION as f; from esphome.arduino8266.framework import TOOLCHAIN_VERSION as t; print(f"{f}-{t}")')
+        key=$(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" >> "$GITHUB_OUTPUT"
    - name: Cache the native toolchain (write on dev)
@@ -19,6 +19,7 @@ on:
      - "esphome/core/**"
      - "esphome/writer.py"
      - "esphome/build_gen/**"
+      - "esphome/build_helpers/**"
      - "esphome/espidf/**"
      - "esphome/platformio/**"
      - "esphome/components/bk72xx/**"
@@ -195,6 +196,7 @@ jobs:
        # the default.
        id:
          - esp8266-arduino
+          - esp8266-arduino-native
          - esp32-arduino-platformio
          - esp32-arduino-esp-idf
          - esp32-idf-platformio
@@ -217,5 +219,6 @@ jobs:
        run: |
          docker run --rm \
            -v "${{ 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"
@@ -299,7 +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
@@ -626,7 +626,7 @@ jobs:
            apt-get install -y libc6-dbg

      - name: Run CodSpeed benchmarks
-        uses: CodSpeedHQ/action@373d6868929f444bc08d901fd0eb0ad52a8875ea # v5.2.1
+        uses: CodSpeedHQ/action@c4fd08a3a159bd0cc208da1e0edf32b8c47d75e5 # v5.4.0
        with:
          run: |
            . venv/bin/activate
@@ -893,14 +893,20 @@ jobs:
      matrix:
        include:
          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 IDF 1/3
-            options: --environment esp32-idf-tidy --split-num 3 --split-at 1
+            name: Run script/clang-tidy for ESP32 IDF 1/5
+            options: --environment esp32-idf-tidy --split-num 5 --split-at 1
          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 IDF 2/3
-            options: --environment esp32-idf-tidy --split-num 3 --split-at 2
+            name: Run script/clang-tidy for ESP32 IDF 2/5
+            options: --environment esp32-idf-tidy --split-num 5 --split-at 2
          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 IDF 3/3
-            options: --environment esp32-idf-tidy --split-num 3 --split-at 3
+            name: Run script/clang-tidy for ESP32 IDF 3/5
+            options: --environment esp32-idf-tidy --split-num 5 --split-at 3
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 IDF 4/5
+            options: --environment esp32-idf-tidy --split-num 5 --split-at 4
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 IDF 5/5
+            options: --environment esp32-idf-tidy --split-num 5 --split-at 5

    steps:
      - name: Check out code from GitHub
@@ -1225,9 +1231,28 @@ 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
@@ -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}}"
@@ -125,14 +125,20 @@ jobs:
            }

            async function getEsphomeAndComponentChanges(github, owner, repo, prNumber) {
-                const changedFiles = await github.rest.pulls.listFiles({
-                    owner: owner,
-                    repo: repo,
-                    pull_number: prNumber,
-                });
+                const changedFiles = await github.paginate(
+                    github.rest.pulls.listFiles,
+                    {
+                        owner: owner,
+                        repo: repo,
+                        pull_number: prNumber,
+                        per_page: 100,
+                    }
+                );

-                const esphomeChanges = changedFiles.data
-                    .filter(file => file.filename !== "esphome/core/defines.h" && file.filename.startsWith('esphome/'))
+                // Files used only for development and CI, which do not affect use as an external component
+                const ignoredFiles = ["esphome/core/defines.h", "esphome/idf_component.yml"];
+                const esphomeChanges = changedFiles
+                    .filter(file => !ignoredFiles.includes(file.filename) && file.filename.startsWith('esphome/'))
                    .map(file => {
                        const match = file.filename.match(/esphome\/([^/]+)/);
                        return match ? match[1] : null;
@@ -144,7 +150,7 @@ jobs:
                }

                const uniqueEsphomeChanges = [...new Set(esphomeChanges)];
-                const componentChanges = changedFiles.data
+                const componentChanges = changedFiles
                    .filter(file => file.filename.startsWith('esphome/components/'))
                    .map(file => {
                        const match = file.filename.match(/esphome\/components\/([^/]+)\//);
@@ -7,10 +7,6 @@ on:
 permissions:
  pull-requests: read  # issues.listLabelsOnIssue to detect blocking labels (needs-docs, needs-developer-docs, merge-after-release, chained-pr)

-concurrency:
-  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
-  cancel-in-progress: true
-
 jobs:
  check:
    name: Check blocking labels
@@ -10,7 +10,7 @@ ci:
 repos:
  - repo: https://github.com/astral-sh/ruff-pre-commit
    # Ruff version.
-    rev: v0.16.8
+    rev: v0.16.10
    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:
@@ -187,10 +187,12 @@ esphome/components/esp32_rmt/* @jesserockz
 esphome/components/esp32_rmt_led_strip/* @jesserockz
 esphome/components/esp8266/* @esphome/core
 esphome/components/esp_ldo/* @clydebarrow
+esphome/components/espectre/* @francescopace
 esphome/components/espnow/* @jesserockz
 esphome/components/espnow/packet_transport/* @EasilyBoredEngineer
 esphome/components/ethernet_info/* @gtjadsonsantos
 esphome/components/event/* @nohat
+esphome/components/exponential_moving_average/* @clydebarrow
 esphome/components/exposure_notifications/* @OttoWinter
 esphome/components/ezo/* @ssieb
 esphome/components/ezo_pmp/* @carlos-sarmiento
@@ -245,8 +247,11 @@ esphome/components/hmac_md5/* @dwmw2
 esphome/components/hmac_sha256/* @dwmw2
 esphome/components/hoermann_hcp/* @zweckj
 esphome/components/homeassistant/* @esphome/core @OttoWinter
+esphome/components/homeassistant/button/* @jesserockz
 esphome/components/homeassistant/number/* @landonr
+esphome/components/homeassistant/select/* @jesserockz
 esphome/components/homeassistant/switch/* @Links2004
+esphome/components/homeassistant/text/* @jesserockz
 esphome/components/honeywell_hih_i2c/* @Benichou34
 esphome/components/honeywellabp/* @RubyBailey
 esphome/components/honeywellabp2_i2c/* @jpfaff
@@ -282,6 +287,7 @@ esphome/components/inkplate/* @jesserockz @JosipKuci
 esphome/components/integration/* @OttoWinter
 esphome/components/internal_temperature/* @Mat931
 esphome/components/interval/* @esphome/core
+esphome/components/ir_rf_base/* @bdraco @kbx81
 esphome/components/ir_rf_proxy/* @kbx81
 esphome/components/it8951/* @koosoli @limengdu @Passific
 esphome/components/jsn_sr04t/* @Mafus1
@@ -541,6 +547,7 @@ 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
@@ -554,12 +561,14 @@ 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/teleinfo/* @0hax @FredM67
 esphome/components/tem3200/* @bakerkj
 esphome/components/template/alarm_control_panel/* @grahambrown11 @hwstar
 esphome/components/template/datetime/* @rfdarter
@@ -599,11 +608,13 @@ 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
 esphome/components/ufm01/* @ljungqvist
 esphome/components/ultrasonic/* @ssieb @swoboda1337
+esphome/components/unicode/* @esphome/core
 esphome/components/update/* @jesserockz
 esphome/components/uponor_smatrix/* @kroimon
 esphome/components/usb_cdc_acm/* @kbx81
@@ -647,6 +658,7 @@ esphome/components/xiaomi_body_scale/* @dckiller51
 esphome/components/xiaomi_hhccjcy10/* @fariouche
 esphome/components/xiaomi_lywsd02mmc/* @juanluss31
 esphome/components/xiaomi_lywsd03mmc/* @ahpohl
+esphome/components/xiaomi_mccgq02hl/* @ahpohl @morph027
 esphome/components/xiaomi_mhoc303/* @drug123
 esphome/components/xiaomi_mhoc401/* @vevsvevs
 esphome/components/xiaomi_rtcgq02lm/* @jesserockz
@@ -48,7 +48,7 @@ PROJECT_NAME           = ESPHome
 # could be handy for archiving the generated documentation or if some version
 # control system is used.

-PROJECT_NUMBER         = 2026.10.0-dev
+PROJECT_NUMBER         = 2026.10.0b4

 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a
@@ -22,7 +22,7 @@ RUN \
    -r /requirements.txt

 # Install the ESPHome Device Builder dashboard.
-RUN uv pip install --no-cache-dir esphome-device-builder==1.17.0
+RUN uv pip install --no-cache-dir esphome-device-builder==1.23.1

 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:
@@ -7,6 +7,7 @@ import importlib
 import logging
 import os
 from pathlib import Path
+import platform
 import re
 import sys
 import time
@@ -18,7 +19,6 @@ from typing import TYPE_CHECKING, Protocol
 from esphome import const, platform_hooks
 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 +36,6 @@ from esphome.const import (
    CONF_LOGGER,
    CONF_MDNS,
    CONF_MQTT,
-    CONF_NAME,
    CONF_NAME_ADD_MAC_SUFFIX,
    CONF_OTA,
    CONF_PASSWORD,
@@ -56,12 +55,13 @@ from esphome.const import (
 )
 from esphome.core import CORE, EsphomeError, coroutine
 from esphome.enum import StrEnum
-from esphome.helpers import get_bool_env, indent, is_ip_address
+from esphome.helpers import IS_MACOS, get_bool_env, indent, is_ip_address
 from esphome.log import AnsiFore, color, setup_log
 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 +85,6 @@ 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 +149,7 @@ class ArgsProtocol(Protocol):
    file: str | None
    no_logs: bool
    only_generate: bool
+    skip_bootloader: bool
    show_secrets: bool
    dashboard: bool
    configuration: str
@@ -829,6 +829,14 @@ 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):
+        # Debug only: an orchestrator cannot see YAML toolchain overrides,
+        # so this is its expected no-op, and a full build is safe.
+        _LOGGER.debug(
+            "--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 +846,7 @@ 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 +867,10 @@ 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 +988,9 @@ 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 +1301,9 @@ 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
@@ -1301,9 +1312,9 @@ def _choose_ota_platform(config: ConfigType, requested: str | None) -> str:
    # platform's final-validate hook merges duplicates anyway.
    available: dict[str, None] = {}
    for ota_item in config.get(CONF_OTA, []):
-        platform = ota_item.get(CONF_PLATFORM)
-        if platform in (CONF_ESPHOME, CONF_WEB_SERVER):
-            available[platform] = None
+        ota_platform = ota_item.get(CONF_PLATFORM)
+        if ota_platform in (CONF_ESPHOME, CONF_WEB_SERVER):
+            available[ota_platform] = None

    if not available:
        raise EsphomeError(
@@ -1381,6 +1392,12 @@ 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:
@@ -1756,6 +1773,18 @@ 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
@@ -1917,7 +1946,10 @@ def run_multiple_configs(
        safe_print()

        cmd = command_builder(f)
-        rc = run_external_process(*cmd)
+        # The parent already logged the Intel macOS warning; children skip it.
+        rc = run_external_process(
+            *cmd, env={**os.environ, _INTEL_MACOS_WARNED_ENV: "1"}
+        )

        if rc == 0:
            print_bar(f"[{color(AnsiFore.BOLD_GREEN, 'SUCCESS')}] {str(f)}")
@@ -2104,155 +2136,9 @@ 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 = {
@@ -2287,6 +2173,15 @@ 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.

@@ -2367,7 +2262,8 @@ 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}."
        ),
    )

@@ -2427,6 +2323,7 @@ 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",
@@ -2490,7 +2387,7 @@ 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)

@@ -2523,6 +2420,7 @@ 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)

@@ -2531,7 +2429,7 @@ 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",
@@ -2720,6 +2618,27 @@ def _warn_if_source_tree_mismatch() -> None:
    )


+_INTEL_MACOS_REMOVAL = "2027.6.0"
+_INTEL_MACOS_WARNED_ENV = "ESPHOME_INTEL_MACOS_WARNED"
+
+
+def _warn_if_intel_macos() -> None:
+    """Warn that Intel (x86_64) Python on macOS loses support by _INTEL_MACOS_REMOVAL."""
+    if (
+        not IS_MACOS
+        or platform.machine() != "x86_64"
+        or _INTEL_MACOS_WARNED_ENV in os.environ
+    ):
+        return
+    _LOGGER.warning(
+        "Support for Intel Macs will end in ESPHome %s or earlier. The Python "
+        "packages ESPHome depends on have stopped publishing Intel macOS builds, "
+        "so future releases will not install on this machine. On an Apple "
+        "Silicon Mac, switch to a native arm64 Python.",
+        _INTEL_MACOS_REMOVAL,
+    )
+
+
 def run_esphome(argv):
    from esphome.address_cache import AddressCache

@@ -2739,6 +2658,7 @@ def run_esphome(argv):

    setup_log(log_level=args.log_level)
    _warn_if_source_tree_mismatch()
+    _warn_if_intel_macos()

    if args.command in PRE_CONFIG_ACTIONS:
        try:
@@ -2782,6 +2702,7 @@ 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
@@ -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
@@ -22,13 +22,69 @@ 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.3",
+        "3af533a85163804e164500a5b254dc23b922080e25ecb7dc37b3dd8ac84651db",
+        37185650,
+    ),
+}
+
+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
    )
@@ -21,7 +21,7 @@ from esphome.const import (
    CONF_TYPE_ID,
    CONF_UPDATE_INTERVAL,
 )
-from esphome.core import CORE, ID, EsphomeError, Lambda
+from esphome.core import CORE, ID, EsphomeError, HexInt, Lambda
 from esphome.cpp_generator import (
    FlashStringLiteral,
    LambdaExpression,
@@ -35,6 +35,32 @@ from esphome.types import ConfigType, SafeExpType
 from esphome.util import Registry


+def progmem_bytes(name: str, data: bytes | list[int]) -> MockObj:
+    """Shared PROGMEM table for constant bytes; equal payloads share one, empty is nullptr."""
+    if not data:
+        return cg.nullptr
+    return cg.shared_progmem_array(
+        name, cg.uint8, cg.ArrayInitializer(*(HexInt(x) for x in data))
+    )
+
+
+async def templatable_bytes(
+    value: Any,
+    args: TemplateArgsType,
+    set_template: MockObj,
+    set_static: MockObj,
+    table_name: str,
+) -> None:
+    """Set a TemplatableBytes: a lambda via set_template, constant bytes via set_static."""
+    if cg.is_template(value):
+        fn = await cg.templatable(value, args, cg.std_vector.template(cg.uint8))
+        cg.add(set_template(fn))
+    elif len(value) > 0xFFFF:
+        raise EsphomeError(f"Byte payload is {len(value)} bytes; the maximum is 65535")
+    else:
+        cg.add(set_static(progmem_bytes(table_name, value), len(value)))
+
+
 def maybe_simple_id(*validators):
    """Allow a raw ID to be specified in place of a config block.
    If the value that's being validated is a dictionary, it's passed as-is to the specified validators. Otherwise, it's
@@ -646,52 +672,20 @@ XorCondition = cg.esphome_ns.class_("XorCondition", Condition)


@register_condition("and", AndCondition, validate_condition_list)
-async def and_condition_to_code(
-    config: ConfigType,
-    condition_id: ID,
-    template_arg: cg.TemplateArguments,
-    args: TemplateArgsType,
-) -> MockObj:
-    conditions = await build_condition_list(config, template_arg, args)
-    return cg.new_Pvariable(
-        condition_id, cg.TemplateArguments(len(conditions), *template_arg), conditions
-    )
-
-
-@register_condition("or", OrCondition, validate_condition_list)
-async def or_condition_to_code(
-    config: ConfigType,
-    condition_id: ID,
-    template_arg: cg.TemplateArguments,
-    args: TemplateArgsType,
-) -> MockObj:
-    conditions = await build_condition_list(config, template_arg, args)
-    return cg.new_Pvariable(
-        condition_id, cg.TemplateArguments(len(conditions), *template_arg), conditions
-    )
-
-
@register_condition("all", AndCondition, validate_condition_list)
-async def all_condition_to_code(
-    config: ConfigType,
-    condition_id: ID,
-    template_arg: cg.TemplateArguments,
-    args: TemplateArgsType,
-) -> MockObj:
-    conditions = await build_condition_list(config, template_arg, args)
-    return cg.new_Pvariable(
-        condition_id, cg.TemplateArguments(len(conditions), *template_arg), conditions
-    )
-
-
+@register_condition("or", OrCondition, validate_condition_list)
@register_condition("any", OrCondition, validate_condition_list)
-async def any_condition_to_code(
+@register_condition("xor", XorCondition, validate_condition_list)
+async def condition_group_to_code(
    config: ConfigType,
    condition_id: ID,
    template_arg: cg.TemplateArguments,
    args: TemplateArgsType,
 ) -> MockObj:
    conditions = await build_condition_list(config, template_arg, args)
+    # A group of one is that condition for and, or and xor; skip the wrapper.
+    if len(conditions) == 1:
+        return conditions[0]
    return cg.new_Pvariable(
        condition_id, cg.TemplateArguments(len(conditions), *template_arg), conditions
    )
@@ -708,19 +702,6 @@ async def not_condition_to_code(
    return cg.new_Pvariable(condition_id, template_arg, condition)


-@register_condition("xor", XorCondition, validate_condition_list)
-async def xor_condition_to_code(
-    config: ConfigType,
-    condition_id: ID,
-    template_arg: cg.TemplateArguments,
-    args: TemplateArgsType,
-) -> MockObj:
-    conditions = await build_condition_list(config, template_arg, args)
-    return cg.new_Pvariable(
-        condition_id, cg.TemplateArguments(len(conditions), *template_arg), conditions
-    )
-
-
@register_condition("lambda", LambdaCondition, cv.returning_lambda)
 async def lambda_condition_to_code(
    config: ConfigType,
@@ -25,6 +25,7 @@ import subprocess
 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,
@@ -36,8 +37,11 @@ from esphome.build_helpers.ninja_gen import (
    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,
@@ -50,6 +54,7 @@ from esphome.components.esp8266.const import (
    KEY_ESP8266,
    KEY_FLASH_SIZE,
    KEY_SCANF_FLOAT,
+    THROW_STUBS_HEADER,
 )
 from esphome.core import CORE, EsphomeError
 from esphome.framework_helpers import get_project_cxx_compile_flags
@@ -1049,24 +1054,22 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
        + ["stdc++-exc" if config.exceptions else "stdc++", "m", "c", "gcc"]
    )

+    cxx = (toolchain_tool(paths.toolchain, "g++"),)
    lines = [
-        *tool_lines(
-            (toolchain_tool(paths.toolchain, "gcc"),),
-            (toolchain_tool(paths.toolchain, "g++"),),
-            ccache,
-        ),
-        *compile_rule_lines(),
+        *tool_lines((toolchain_tool(paths.toolchain, "gcc"),), cxx, ccache),
+        *compile_rule_lines(ccache),
        *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",
@@ -1085,33 +1088,10 @@ def write_project(paths: InstalledPaths, ccache: str | None) -> bool:
    if "USE_ESP8266_WAVEFORM_STUBS" in flag_defines:
        core_exclude |= _CORE_EXCLUDE_WAVEFORM

-    archives = []
-    # variant_dir existence was already enforced with the include dirs
-    variant_sources = collect_sources(variant_dir)
-    if variant_sources:
-        objs = compile_edges(lines, variant_sources, variant_dir, "variant")
-        lines.append(f"build libFrameworkArduinoVariant.a: ar {' '.join(objs)}")
-        archives.append("libFrameworkArduinoVariant.a")
-
-    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
-        # (app_entry, the exception vectors) far from the cause
-        raise EsphomeError(
-            f"{_INCOMPLETE_INSTALL}: no core sources in {core_dir}; {_CLEAN_HINT}"
-        )
-    lines.append(f"build libFrameworkArduino.a: ar {' '.join(core_objs)}")
-    archives.append("libFrameworkArduino.a")
-
-    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] = []
+    # esp8266/__init__ pins build_src_flags (the throw_stubs force-include), as on
+    # the PlatformIO path; -include paths resolve against the source root
+    src_other: list[str] = []
+    src_includes: list[str] = []
    src_it = iter(
        lex_build_flags(_pio_option("build_src_flags", ""), "build_src_flags")
    )
@@ -1122,15 +1102,71 @@ 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))
+    # The throw stubs abort: none anywhere with exceptions on, else the core and
+    # libraries get them too (src keeps them after its pch include)
+    if config.exceptions:
+        src_includes = [h for h in src_includes if h != THROW_STUBS_HEADER]
+    include_flags = [f"-include {_q(src_dir / h)}" for h in src_includes]
+    framework_flags = ""
+    if THROW_STUBS_HEADER in src_includes:
+        stubs_flag = include_flags[src_includes.index(THROW_STUBS_HEADER)]
+        lines.append(f"frameworkflags = {stubs_flag}")
+        framework_flags = "$frameworkflags"
+    archives = []
+    # variant_dir existence was already enforced with the include dirs
+    variant_sources = collect_sources(variant_dir)
+    if variant_sources:
+        objs = compile_edges(
+            lines, variant_sources, variant_dir, "variant", flags=framework_flags
+        )
+        lines.append(f"build libFrameworkArduinoVariant.a: ar {' '.join(objs)}")
+        archives.append("libFrameworkArduinoVariant.a")
+
+    core_objs = compile_edges(
+        lines,
+        collect_sources(core_dir, core_exclude),
+        core_dir,
+        "core",
+        flags=framework_flags,
+    )
+    if not core_objs:
+        # An empty archive would link into a wall of undefined references
+        # (app_entry, the exception vectors) far from the cause
+        raise EsphomeError(
+            f"{_INCOMPLETE_INSTALL}: no core sources in {core_dir}; {_CLEAN_HINT}"
+        )
+    lines.append(f"build libFrameworkArduino.a: ar {' '.join(core_objs)}")
+    archives.append("libFrameworkArduino.a")
+
+    lib_archives, direct_objs = library_edges(lines, libraries, framework_flags)
+    archives += lib_archives
+
    # One shared variable instead of repeating the flags line on every src
    # edge (hundreds of edges in a real project)
-    lines.append(f"srcflags = {src_extra}")
+    lines.append(f"srcflags = {' '.join(src_other + include_flags)}")
+    src_cxx_override = pch_edges(
+        lines,
+        build_dir,
+        src_dir,
+        (*src_includes, *PCH_DEFAULT_HEADERS),
+        flag_sets.cxxflags,
+        src_other,
+        (str(paths.framework), str(paths.toolchain)),
+        cxx,
+    )
    src_objs = compile_edges(
-        lines, collect_sources(src_dir), src_dir, "src", flags="$srcflags"
+        lines,
+        collect_sources(src_dir),
+        src_dir,
+        "src",
+        flags="$srcflags",
+        cxx_override=src_cxx_override,
    )

    ld_deps = [f"ld/{_COMMON_LD_NAME}"]
@@ -1168,3 +1204,28 @@ 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 +158,85 @@ 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 a few 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(${sdkconfig_cmake})
+        set(CONFIG_APP_BUILD_BOOTLOADER "")
+        # bt's CMakeLists reads the lowercase idf_target that the (now
+        # skipped) bootloader project_include leaks; keep it defined, or
+        # its empty TARGET_SRC_NAME sends file(GLOB_RECURSE) across /.
+        idf_build_get_property(idf_target IDF_TARGET)
+        # partition_table's V1 ECDSA signing reads this key, which the
+        # skipped bootloader project_include also sets.
+        get_filename_component(SECURE_BOOT_SIGNING_KEY "${CONFIG_SECURE_BOOT_SIGNING_KEY}" ABSOLUTE BASE_DIR "${project_dir}")
+        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)",
+    (
+        "get_filename_component(SECURE_BOOT_SIGNING_KEY"
+        ' "${CONFIG_SECURE_BOOT_SIGNING_KEY}" ABSOLUTE BASE_DIR "${project_dir}")'
+    ),
+)
+
+_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 +282,22 @@ 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 +375,9 @@ 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 +390,22 @@ 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 ${{CMAKE_BINARY_DIR}}
    VERBATIM
 )
@@ -282,9 +468,72 @@ idf_component_register(
 target_link_options(${{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:
@@ -15,6 +15,7 @@ from collections.abc import Iterable
 import logging
 import os
 from pathlib import Path
+import subprocess
 import sys
 from typing import TYPE_CHECKING

@@ -28,8 +29,11 @@ from esphome.build_helpers.ninja_gen import (
    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
@@ -189,6 +193,15 @@ def _file_macro_maps(build_dir: Path) -> list[str]:
    ]


+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.

@@ -227,7 +240,8 @@ def write_project(compilers: HostCompilers, ccache: str | None) -> bool:

    lines = [
        *tool_lines(compilers.cc, compilers.cxx, ccache),
-        *compile_rule_lines(),
+        *compile_rule_lines(ccache),
+        *pch_rule_lines(),
        "rule link",
        "  command = $cxx -o $out $linkflags @$out.rsp $archives $libdirflags $libflags",
        "  rspfile = $out.rsp",
@@ -251,7 +265,24 @@ def write_project(compilers: HostCompilers, ccache: str | None) -> bool:

    archives, direct_objs = library_edges(lines, libraries)

-    src_objs = compile_edges(lines, collect_sources(src_dir), src_dir, "src")
+    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}")

@@ -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"
@@ -102,15 +102,30 @@ def ccache_defaults_env(cache_dir: Path) -> dict[str, str]:
    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.
+    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

-    return ccache_defaults_env(tools_cache_path(*tools_cache) / "ccache")
+    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]]:
@@ -13,12 +13,23 @@ 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:
@@ -63,37 +74,102 @@ def tool_lines(
        # path gets
        f"python = {_q(strip_win_long_path_prefix(sys.executable))}",
        f"buildtool = {_q(_BUILD_TOOL)}",
-        f"ccache = {_q(ccache) if ccache else ''}",
+        *([f"ccache = {_q(ccache)}"] if ccache else []),
        "",
    ]


-def compile_rule_lines() -> list[str]:
-    """The compile rules; ``$own_includes`` is empty unless an edge sets it."""
+def compile_rule_lines(ccache: str | None) -> list[str]:
+    """The compile rules; ``$own_includes`` is empty unless an edge sets it.
+
+    ``ccache`` is the launcher ``tool_lines`` was given; the same test here
+    keeps the variable and the rules in step. It is spliced in rather than
+    left as an empty variable: a leading space on the command line makes
+    CreateProcess fail on Windows.
+    """
+    launcher = "$ccache " if ccache else ""
    return [
        "rule c",
-        "  command = $ccache $cc -MMD -MF $out.d $own_includes $cflags $flags -c $in -o $out",
+        f"  command = {launcher}$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 $out",
+        f"  command = {launcher}$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 $out",
+        f"  command = {launcher}$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 $out",
+        f"  command = {launcher}$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",
@@ -111,20 +187,26 @@ def compile_edges(
    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."""
+    """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)
-        lines.append(
-            f"build {escaped_obj}: {SOURCE_KIND_FOR_SUFFIX[src.suffix]} {_e(src)}"
-        )
+        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 flags:
-            lines.append(f"  flags = {flags}")
+        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)
@@ -132,10 +214,12 @@ def compile_edges(


 def library_edges(
-    lines: list[str], libraries: list[ArduinoLibrary]
+    lines: list[str], libraries: list[ArduinoLibrary], extra_flags: str = ""
 ) -> tuple[list[str], list[str]]:
    """Emit every library's compile and archive edges.

+    ``extra_flags`` (raw ninja text) precede each library's own flags.
+
    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
@@ -157,7 +241,7 @@ def library_edges(
            lib.sources,
            common_parent(lib.sources),
            f"lib/{lib.name}",
-            flags=" ".join(_shell_token(f) for f in lib.flags),
+            flags=" ".join(filter(None, [extra_flags, *map(_shell_token, lib.flags)])),
            own_includes=" ".join(f"-I{_q(d)}" for d in lib.include_dirs),
        )
        if not lib.lib_archive:
@@ -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
@@ -35,9 +35,12 @@ SDK_NRF_TOOLS_CACHE = ("ESPHOME_SDK_NRF_PREFIX", "sdk-nrf")
 ARDUINO8266_TOOLS_CACHE = ("ESPHOME_ARDUINO8266_PREFIX", "arduino8266")
 # 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
@@ -31,6 +31,7 @@ from esphome.cpp_generator import (  # noqa: F401
    add_global,
    add_library,
    add_platformio_option,
+    extern_progmem_array,
    get_variable,
    get_variable_with_full_id,
    is_template,
@@ -40,6 +41,7 @@ from esphome.cpp_generator import (  # noqa: F401
    progmem_array,
    safe_exp,
    set_cpp_standard,
+    shared_progmem_array,
    statement,
    static_const_array,
    static_function,
@@ -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)
@@ -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)
@@ -1,3 +1,4 @@
+from ipaddress import IPv4Address, IPv6Address
 import logging
 import re
 from typing import Any
@@ -5,7 +6,7 @@ from typing import Any
 from esphome import automation
 from esphome.automation import Condition
 import esphome.codegen as cg
-from esphome.components.const import CONF_DESCRIPTION
+from esphome.components.const import CONF_DESCRIPTION, CONF_HOST
 from esphome.components.logger import request_log_listener

 # ENCRYPTION_SCHEMA and validate_encryption_key are re-exported for external
@@ -13,6 +14,7 @@ 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,
@@ -25,6 +27,8 @@ from esphome.const import (
    CONF_CAPTURE_RESPONSE,
    CONF_DATA,
    CONF_DATA_TEMPLATE,
+    CONF_DELAY,
+    CONF_ENABLE_IPV6,
    CONF_ENCRYPTION,
    CONF_EVENT,
    CONF_ID,
@@ -47,10 +51,14 @@ from esphome.const import (
    CONF_VARIABLES,
 )
 from esphome.core import CORE, ID, CoroPriority, EsphomeError, coroutine_with_priority
-from esphome.cpp_generator import MockObj, TemplateArgsType
-from esphome.helpers import fnv1_hash
+from esphome.cpp_generator import Expression, MockObj, TemplateArgsType
+import esphome.final_validate as fv
+from esphome.helpers import cpp_string_escape, fnv1_hash
+from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
 from esphome.types import ConfigFragmentType, ConfigType

+from . import wizard
+
 # Compat alias: downstream consumers (e.g. device-builder) referenced the
 # schema by its old private name before it moved to the noise component
 _encryption_schema = encryption_schema
@@ -85,6 +93,7 @@ APIServer = api_ns.class_("APIServer", cg.Component)
 HomeAssistantServiceCallAction = api_ns.class_(
    "HomeAssistantServiceCallAction", automation.Action
 )
+HomeAssistantField = api_ns.struct("HomeAssistantField")
 ActionResponse = api_ns.class_("ActionResponse")
 HomeAssistantActionResponseTrigger = api_ns.class_(
    "HomeAssistantActionResponseTrigger", automation.Trigger
@@ -134,6 +143,7 @@ CONF_HOMEASSISTANT_SERVICES = "homeassistant_services"
 CONF_HOMEASSISTANT_STATES = "homeassistant_states"
 CONF_LISTEN_BACKLOG = "listen_backlog"
 CONF_MAX_SEND_QUEUE = "max_send_queue"
+CONF_OUTGOING_CONNECTION = "outgoing_connection"
 CONF_STATE_SUBSCRIPTION_ONLY = "state_subscription_only"

 # Schema defaults that also match the C++ initializers in api_server.h; codegen
@@ -141,6 +151,7 @@ CONF_STATE_SUBSCRIPTION_ONLY = "state_subscription_only"
 DEFAULT_PORT = 6053
 DEFAULT_REBOOT_TIMEOUT = "15min"
 DEFAULT_BATCH_DELAY = "100ms"
+DEFAULT_LISTEN_BACKLOG = 4


 def _register_provisioning_source(config: ConfigType) -> ConfigType:
@@ -291,9 +302,72 @@ def _consume_api_sockets(config: ConfigType) -> ConfigType:
    # (not max_connections, which is the upper limit rarely reached)
    socket.consume_sockets(3, "api")(config)
    socket.consume_sockets(1, "api", socket.SocketType.TCP_LISTEN)(config)
+    if CONF_OUTGOING_CONNECTION in config:
+        socket.consume_sockets(1, "api_outgoing_connection")(config)
    return config


+def _validate_outgoing_connection(config: ConfigType) -> ConfigType:
+    if (outgoing := config.get(CONF_OUTGOING_CONNECTION)) is None:
+        return config
+    if CONF_ENCRYPTION not in config:
+        raise cv.Invalid(
+            "outgoing_connection requires 'encryption' so the peer is verified by key",
+            path=[CONF_OUTGOING_CONNECTION],
+        )
+    # A device with no client reboots once reboot_timeout passes, so a delay that
+    # reaches it would reboot the device before it ever dials
+    reboot_timeout = config[CONF_REBOOT_TIMEOUT]
+    delay = outgoing[CONF_DELAY]
+    if reboot_timeout.total_milliseconds and delay >= reboot_timeout:
+        raise cv.Invalid(
+            f"delay must be shorter than reboot_timeout ({reboot_timeout}), "
+            "otherwise the device reboots before it dials",
+            path=[CONF_OUTGOING_CONNECTION, CONF_DELAY],
+        )
+    return config
+
+
+def _validate_outgoing_host(value: str) -> IPv4Address | IPv6Address:
+    """Only accept an address the device itself can parse.
+
+    Python accepts a scope id, which neither `inet_pton` nor lwIP's `inet6_aton`
+    takes, and a v4-mapped address is dialed as plain IPv4, needing no IPv6 build.
+    """
+    address = cv.ipaddress(value)
+    if isinstance(address, IPv6Address):
+        if address.scope_id is not None:
+            raise cv.Invalid(
+                f"{value} carries a scope id, which the device cannot parse; "
+                "give the address without the '%' part"
+            )
+        if (mapped := address.ipv4_mapped) is not None:
+            return mapped
+    return address
+
+
+_OUTGOING_CONNECTION_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_HOST): _validate_outgoing_host,
+        cv.Optional(CONF_PORT, default=6054): cv.port,
+        # Bounded against reboot_timeout in _validate_outgoing_connection
+        cv.Optional(CONF_DELAY, default="60s"): cv.positive_time_period_milliseconds,
+    }
+)
+
+
+@schema_extractor("schema")
+def _outgoing_connection_schema(config: ConfigType | None) -> ConfigType:
+    # A bare `outgoing_connection:` block is valid; without a host the device
+    # dials the remembered last dial-back client
+    if config is SCHEMA_EXTRACT:
+        # Let the language-schema dumper walk host, port and delay
+        return _OUTGOING_CONNECTION_SCHEMA
+    if config is None:
+        config = {}
+    return _OUTGOING_CONNECTION_SCHEMA(config)
+
+
 CONFIG_SCHEMA = cv.All(
    cv.Schema(
        {
@@ -318,6 +392,8 @@ CONFIG_SCHEMA = cv.All(
            ): ACTIONS_SCHEMA,
            cv.Exclusive(CONF_ACTIONS, group_of_exclusion=CONF_ACTIONS): ACTIONS_SCHEMA,
            cv.Optional(CONF_ENCRYPTION): encryption_schema,
+            cv.Optional(wizard.CONF_WIZARD): wizard.WIZARD_SCHEMA,
+            cv.Optional(CONF_OUTGOING_CONNECTION): _outgoing_connection_schema,
            cv.Optional(CONF_BATCH_DELAY, default=DEFAULT_BATCH_DELAY): cv.All(
                cv.positive_time_period_milliseconds,
                cv.Range(max=cv.TimePeriod(milliseconds=65535)),
@@ -373,6 +449,7 @@ CONFIG_SCHEMA = cv.All(
        }
    ).extend(cv.COMPONENT_SCHEMA),
    cv.rename_key(CONF_SERVICES, CONF_ACTIONS),
+    _validate_outgoing_connection,
    _consume_api_sockets,
    _register_provisioning_source,
 )
@@ -429,7 +506,34 @@ def _validate_esp8266_action_strings(config: ConfigType) -> ConfigType:
    return config


-FINAL_VALIDATE_SCHEMA = _validate_esp8266_action_strings
+def _validate_outgoing_host_ipv6(config: ConfigType) -> ConfigType:
+    """An IPv6 host can never be parsed, so never dialed, without IPv6."""
+    if (
+        (outgoing := config.get(CONF_OUTGOING_CONNECTION)) is None
+        or (host := outgoing.get(CONF_HOST)) is None
+        or host.version != 6
+    ):
+        return config
+    network_conf = fv.full_config.get().get("network") or {}
+    if not network_conf.get(CONF_ENABLE_IPV6):
+        raise cv.Invalid(
+            "outgoing_connection host is an IPv6 address but IPv6 is not "
+            "enabled; set 'network: enable_ipv6: true'",
+            path=[CONF_OUTGOING_CONNECTION, CONF_HOST],
+        )
+    return config
+
+
+def _validate_wizard(config: ConfigType) -> ConfigType:
+    wizard.final_validate(config)
+    return config
+
+
+FINAL_VALIDATE_SCHEMA = cv.All(
+    _validate_esp8266_action_strings,
+    _validate_outgoing_host_ipv6,
+    _validate_wizard,
+)


 def _add_action_strings(
@@ -476,8 +580,10 @@ async def to_code(config: ConfigType) -> None:
        cg.add(var.set_reboot_timeout(reboot_timeout))
    if (batch_delay := config[CONF_BATCH_DELAY]) != cv.time_period(DEFAULT_BATCH_DELAY):
        cg.add(var.set_batch_delay(batch_delay))
-    if CONF_LISTEN_BACKLOG in config:
-        cg.add(var.set_listen_backlog(config[CONF_LISTEN_BACKLOG]))
+    if (
+        listen_backlog := config.get(CONF_LISTEN_BACKLOG)
+    ) is not None and listen_backlog != DEFAULT_LISTEN_BACKLOG:
+        cg.add(var.set_listen_backlog(listen_backlog))
    cg.add_define("MAX_API_CONNECTIONS", config[CONF_MAX_CONNECTIONS])
    cg.add_define("API_MAX_SEND_QUEUE", config[CONF_MAX_SEND_QUEUE])

@@ -582,6 +688,9 @@ async def to_code(config: ConfigType) -> None:
        # Stack buffer that list-entities copies PROGMEM strings into, sized for the largest action
        cg.add_define("API_USER_ACTION_STRINGS_SCRATCH_SIZE", max(scratch_size, 1))

+    if (wizard_config := config.get(wizard.CONF_WIZARD)) is not None:
+        await wizard.to_code(wizard_config)
+
    if CONF_ON_CLIENT_CONNECTED in config:
        cg.add_define("USE_API_CLIENT_CONNECTED_TRIGGER")
        await automation.build_automation(
@@ -600,7 +709,7 @@ 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
@@ -613,9 +722,17 @@ 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")

+    if (outgoing := config.get(CONF_OUTGOING_CONNECTION)) is not None:
+        cg.add_define("USE_API_OUTGOING_CONNECTION")
+        if (host := outgoing.get(CONF_HOST)) is not None:
+            cg.add_define("API_OUTGOING_CONNECTION_HOST", str(host))
+        cg.add_define("API_OUTGOING_CONNECTION_PORT", outgoing[CONF_PORT])
+        cg.add_define("API_OUTGOING_CONNECTION_DELAY", outgoing[CONF_DELAY])
+
    cg.add_define("USE_API")
    cg.add_global(api_ns.using)

@@ -656,6 +773,11 @@ VARIABLES_SCHEMA = cv.Schema(
    {cv.string: cv.All(_coerce_implicit_lambda, cv.templatable(cv.string_strict))}
 )

+# The action stores each map's entry count in a uint8_t
+_FIELD_MAP_MAX = 255
+DATA_FIELDS_SCHEMA = cv.All(KEY_VALUE_SCHEMA, cv.Length(max=_FIELD_MAP_MAX))
+VARIABLES_FIELDS_SCHEMA = cv.All(VARIABLES_SCHEMA, cv.Length(max=_FIELD_MAP_MAX))
+

 def _validate_response_config(config: ConfigType) -> ConfigType:
    # Validate dependencies:
@@ -690,9 +812,9 @@ HOMEASSISTANT_ACTION_ACTION_SCHEMA = cv.All(
            cv.Exclusive(CONF_ACTION, group_of_exclusion=CONF_ACTION): cv.templatable(
                cv.string
            ),
-            cv.Optional(CONF_DATA, default={}): KEY_VALUE_SCHEMA,
-            cv.Optional(CONF_DATA_TEMPLATE, default={}): KEY_VALUE_SCHEMA,
-            cv.Optional(CONF_VARIABLES, default={}): VARIABLES_SCHEMA,
+            cv.Optional(CONF_DATA, default={}): DATA_FIELDS_SCHEMA,
+            cv.Optional(CONF_DATA_TEMPLATE, default={}): DATA_FIELDS_SCHEMA,
+            cv.Optional(CONF_VARIABLES, default={}): VARIABLES_FIELDS_SCHEMA,
            cv.Optional(CONF_RESPONSE_TEMPLATE): cv.templatable(cv.string),
            cv.Optional(CONF_CAPTURE_RESPONSE, default=False): cv.boolean,
            cv.Optional(CONF_ON_SUCCESS): automation.validate_automation(single=True),
@@ -705,6 +827,62 @@ HOMEASSISTANT_ACTION_ACTION_SCHEMA = cv.All(
 )


+def _field_string(value: str) -> Expression:
+    # ESP8266 can only keep a string in flash as its own PROGMEM array
+    literal = cg.RawExpression(cpp_string_escape(value))
+    if CORE.is_esp8266:
+        return cg.shared_progmem_array("ha_field_str", cg.char, literal)
+    return literal
+
+
+async def _new_service_call_action(
+    server_id: ID,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+    is_event: bool,
+    service: Any,
+    data: dict[str, Any],
+    data_template: dict[str, Any],
+    variables: dict[str, Any],
+) -> MockObj:
+    """Create the action with its name and fields in one shared flash table."""
+    cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
+    serv = await cg.get_variable(server_id)
+    field_type = HomeAssistantField.template(template_arg)
+    groups = [data, data_template, variables]
+    # A lambda may keep static state, so a table with lambdas is never shared
+    has_lambda = cg.is_template(service) or any(
+        cg.is_template(value) for group in groups for value in group.values()
+    )
+
+    async def field(key: str | None, value: Any, output_type: Any = None) -> Expression:
+        key_exp = cg.nullptr if key is None else _field_string(key)
+        if cg.is_template(value):
+            # output_type=None lets lambdas return numbers or char pointers; C++ converts them
+            lam = await cg.process_lambda(value, args, return_type=output_type)
+            return cg.RawExpression(f"{field_type}::from_lambda({key_exp}, {lam})")
+        return cg.ArrayInitializer(key_exp, _field_string(value), cg.nullptr)
+
+    entries = [await field(None, service, cg.std_string)]
+    for group in groups:
+        for key, value in group.items():
+            entries.append(await field(key, value))
+    table = cg.shared_progmem_array(
+        "ha_action_fields",
+        field_type,
+        cg.ArrayInitializer(*entries, multiline=True),
+        share=not has_lambda,
+    )
+    return cg.new_Pvariable(
+        action_id, template_arg, serv, is_event, table, *(len(g) for g in groups)
+    )
+
+
+def _service_call_fields(config: ConfigType) -> tuple[dict[str, Any], ...]:
+    return config[CONF_DATA], config[CONF_DATA_TEMPLATE], config[CONF_VARIABLES]
+
+
 # synchronous=False: when on_success/on_error is configured, play() stores the
 # trigger args until the HomeassistantActionResponse arrives, so non-owning args
 # (StringRef into the API receive buffer) must not be used.
@@ -726,36 +904,15 @@ async def homeassistant_service_to_code(
    template_arg: cg.TemplateArguments,
    args: TemplateArgsType,
 ) -> MockObj:
-    cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
-    serv = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, serv, False)
-    templ = await cg.templatable(config[CONF_ACTION], args, cg.std_string)
-    cg.add(var.set_service(templ))
-
-    # Initialize FixedVectors with exact sizes from config
-    cg.add(var.init_data(len(config[CONF_DATA])))
-    for key, value in config[CONF_DATA].items():
-        # output_type=None because lambdas can return non-string types (int,
-        # float, char*) that TemplatableStringValue converts via to_string.
-        # Static strings are manually wrapped for PROGMEM on ESP8266.
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_data(cg.FlashStringLiteral(key), templ))
-
-    cg.add(var.init_data_template(len(config[CONF_DATA_TEMPLATE])))
-    for key, value in config[CONF_DATA_TEMPLATE].items():
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_data_template(cg.FlashStringLiteral(key), templ))
-
-    cg.add(var.init_variables(len(config[CONF_VARIABLES])))
-    for key, value in config[CONF_VARIABLES].items():
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_variable(cg.FlashStringLiteral(key), templ))
+    var = await _new_service_call_action(
+        config[CONF_ID],
+        action_id,
+        template_arg,
+        args,
+        False,
+        config[CONF_ACTION],
+        *_service_call_fields(config),
+    )

    if on_error := config.get(CONF_ON_ERROR):
        cg.add_define("USE_API_HOMEASSISTANT_ACTION_RESPONSES")
@@ -807,9 +964,9 @@ HOMEASSISTANT_EVENT_ACTION_SCHEMA = cv.Schema(
    {
        cv.GenerateID(): cv.use_id(APIServer),
        cv.Required(CONF_EVENT): validate_homeassistant_event,
-        cv.Optional(CONF_DATA, default={}): KEY_VALUE_SCHEMA,
-        cv.Optional(CONF_DATA_TEMPLATE, default={}): KEY_VALUE_SCHEMA,
-        cv.Optional(CONF_VARIABLES, default={}): VARIABLES_SCHEMA,
+        cv.Optional(CONF_DATA, default={}): DATA_FIELDS_SCHEMA,
+        cv.Optional(CONF_DATA_TEMPLATE, default={}): DATA_FIELDS_SCHEMA,
+        cv.Optional(CONF_VARIABLES, default={}): VARIABLES_FIELDS_SCHEMA,
    }
 )

@@ -828,38 +985,15 @@ async def homeassistant_event_to_code(
    template_arg: cg.TemplateArguments,
    args: TemplateArgsType,
 ) -> MockObj:
-    cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
-    serv = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, serv, True)
-    templ = await cg.templatable(config[CONF_EVENT], args, cg.std_string)
-    cg.add(var.set_service(templ))
-
-    # Initialize FixedVectors with exact sizes from config
-    cg.add(var.init_data(len(config[CONF_DATA])))
-    for key, value in config[CONF_DATA].items():
-        # output_type=None because lambdas can return non-string types (int,
-        # float, char*) that TemplatableStringValue converts via to_string.
-        # Static strings are manually wrapped for PROGMEM on ESP8266.
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_data(cg.FlashStringLiteral(key), templ))
-
-    cg.add(var.init_data_template(len(config[CONF_DATA_TEMPLATE])))
-    for key, value in config[CONF_DATA_TEMPLATE].items():
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_data_template(cg.FlashStringLiteral(key), templ))
-
-    cg.add(var.init_variables(len(config[CONF_VARIABLES])))
-    for key, value in config[CONF_VARIABLES].items():
-        templ = await cg.templatable(value, args, None)
-        if isinstance(templ, str):
-            templ = cg.FlashStringLiteral(templ)
-        cg.add(var.add_variable(cg.FlashStringLiteral(key), templ))
-
-    return var
+    return await _new_service_call_action(
+        config[CONF_ID],
+        action_id,
+        template_arg,
+        args,
+        True,
+        config[CONF_EVENT],
+        *_service_call_fields(config),
+    )


 HOMEASSISTANT_TAG_SCANNED_ACTION_SCHEMA = cv.maybe_simple_value(
@@ -883,15 +1017,17 @@ async def homeassistant_tag_scanned_to_code(
    template_arg: cg.TemplateArguments,
    args: TemplateArgsType,
 ) -> MockObj:
-    cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
-    serv = await cg.get_variable(config[CONF_ID])
-    var = cg.new_Pvariable(action_id, template_arg, serv, True)
-    cg.add(var.set_service(cg.FlashStringLiteral("esphome.tag_scanned")))
-    # Initialize FixedVector with exact size (1 data field)
-    cg.add(var.init_data(1))
-    templ = await cg.templatable(config[CONF_TAG], args, cg.std_string)
-    cg.add(var.add_data(cg.FlashStringLiteral("tag_id"), templ))
-    return var
+    return await _new_service_call_action(
+        config[CONF_ID],
+        action_id,
+        template_arg,
+        args,
+        True,
+        "esphome.tag_scanned",
+        {"tag_id": config[CONF_TAG]},
+        {},
+        {},
+    )


 CONF_SUCCESS = "success"
@@ -1002,6 +1138,8 @@ _define_filter = filter_source_files_from_defines(
        "user_services.cpp": "USE_API_USER_DEFINED_ACTIONS",
        "api_frame_helper_noise.cpp": "USE_API_NOISE",
        "api_frame_helper_plaintext.cpp": "USE_API_PLAINTEXT",
+        "api_wizard.cpp": "USE_API_WIZARD",
+        "api_outgoing_connection.cpp": "USE_API_OUTGOING_CONNECTION",
    }
 )

@@ -20,6 +20,8 @@ service APIConnection {
    option (needs_authentication) = false;
  }
  rpc device_capabilities (DeviceCapabilitiesRequest) returns (DeviceCapabilitiesResponse) {}
+  rpc device_wizard (DeviceWizardRequest) returns (DeviceWizardResponse) {}
+  rpc wizard_input_set (WizardInputSetRequest) returns (void) {}
  rpc list_entities (ListEntitiesRequest) returns (void) {}
  rpc subscribe_states (SubscribeStatesRequest) returns (void) {}
  rpc subscribe_logs (SubscribeLogsRequest) returns (void) {}
@@ -76,8 +78,11 @@ service APIConnection {
  rpc serial_proxy_write(SerialProxyWriteRequest) returns (void) {}
  rpc serial_proxy_set_modem_pins(SerialProxySetModemPinsRequest) returns (void) {}
  rpc serial_proxy_get_modem_pins(SerialProxyGetModemPinsRequest) returns (void) {}
+  rpc subscribe_serial_proxy_identity(SubscribeSerialProxyIdentityRequest) returns (void) {}
  rpc serial_proxy_request(SerialProxyRequest) returns (void) {}
  rpc serial_proxy_set_mode(SerialProxySetModeRequest) returns (void) {}
+
+  rpc sendspin_pairing_token(SendspinPairingTokenRequest) returns (SendspinPairingTokenResponse) {}
 }


@@ -113,6 +118,11 @@ message HelloRequest {
  string client_info = 1;
  uint32 api_version_major = 2;
  uint32 api_version_minor = 3;
+
+  // Set by clients that can accept connections the device opens to them
+  // (see api: outgoing_connection:). The device remembers this client's
+  // address as the target to dial when no such client is connected.
+  bool outgoing_connection_target = 4 [(field_ifdef) = "USE_API_OUTGOING_CONNECTION"];
 }

 // Confirmation of successful connection request.
@@ -228,6 +238,7 @@ enum SerialProxyPortType {
  SERIAL_PROXY_PORT_TYPE_TTL = 0;
  SERIAL_PROXY_PORT_TYPE_RS232 = 1;
  SERIAL_PROXY_PORT_TYPE_RS485 = 2;
+  SERIAL_PROXY_PORT_TYPE_USB_SERIAL = 3;  // since API 1.18
 }

 message SerialProxyInfo {
@@ -332,6 +343,10 @@ message DeviceInfoResponse {
  // all-zeros PSK, so the api encryption key can be provisioned without being
  // sent in plaintext (protects against passive sniffing, not active MITM)
  bool api_encryption_provisionable = 26 [(field_ifdef) = "USE_API_NOISE"];
+
+  // Device is built with the api outgoing_connection option and can open
+  // the TCP connection to a dial-back target itself
+  bool api_outgoing_connection_supported = 27 [(field_ifdef) = "USE_API_OUTGOING_CONNECTION"];
 }

 // ==================== DEVICE CAPABILITIES ====================
@@ -380,6 +395,16 @@ message ZWaveProxyCapabilities {
  uint32 home_id = 2;
 }

+message WizardCapabilities {
+  // True when the device has a wizard configured, so DeviceWizardRequest will be answered
+  bool configured = 1;
+}
+
+message SendspinCapabilities {
+  // Bitmask of the Sendspin features this device supports
+  uint32 feature_flags = 1;
+}
+
 message DeviceCapabilitiesResponse {
  option (id) = 150;
  option (source) = SOURCE_SERVER;
@@ -389,6 +414,102 @@ message DeviceCapabilitiesResponse {
  ZWaveProxyCapabilities zwave_proxy = 3 [(field_ifdef) = "USE_ZWAVE_PROXY"];
  repeated SerialProxyInfo serial_proxies = 4
      [(field_ifdef) = "USE_SERIAL_PROXY", (fixed_array_size_define) = "SERIAL_PROXY_COUNT"];
+  WizardCapabilities wizard = 5 [(field_ifdef) = "USE_API_WIZARD"];
+  SendspinCapabilities sendspin = 6 [(field_ifdef) = "USE_SENDSPIN"];
+}
+
+// ==================== DEVICE WIZARD ====================
+
+// Asks the device for the onboarding wizard that Home Assistant presents when the
+// device is added.
+//
+// The wizard is read once, when the device is added, whereas capabilities are read
+// on every connect, so it is a separate message rather than part of
+// DeviceCapabilitiesResponse. It is only served on an authenticated connection.
+//
+// A device without a wizard does not have this message at all and never answers it,
+// as a device ignores messages it does not know. Clients therefore check
+// DeviceCapabilitiesResponse.wizard.configured before sending it.
+message DeviceWizardRequest {
+  option (id) = 156;
+  option (source) = SOURCE_CLIENT;
+  option (ifdef) = "USE_API_WIZARD";
+  // Empty
+}
+
+// The wizard, as UTF-8 JSON compressed into a single zstd frame. The device builds it
+// when it is compiled and sends it unchanged, so its size varies with the wizard and
+// its format can grow without new fields here. Clients decompress it, then read:
+//
+//   {"version": 1,
+//    "pages": [{"title": "...", "description": "...",
+//      "entities": [{"key": 123, "device_id": 456, "description": "..."}],
+//      "inputs": [{"key": 789, "description": "...", "multiple": true, "max_length": 1023,
+//        "entity_filters": [{"integration": "...", "domain": ["..."],
+//                            "device_class": ["..."], "supported_features": ["..."]}]}]}]}
+//
+// Values that are empty or unset are left out, and so are empty lists. Strings may be
+// Home Assistant translation placeholders such as "[%key:component::domain::name%]",
+// passed through verbatim. The pages are shown in the order listed. A client that does
+// not know the version must not use the wizard.
+//
+// An entity is an entity of this device that the page shows to the user (for example to
+// turn it on or off). Its key is the key ListEntitiesResponse sends for it. Its
+// device_id is the device_id ListEntitiesResponse sends, and is left out when that is 0.
+//
+// An input is filled in by the user with the id of a Home Assistant entity. It either
+// stands for one entity of the device's homeassistant platform (sensor, binary_sensor,
+// text_sensor, number, switch, text, select or button) that sets no entity_id of its own,
+// as Home Assistant supplies it, or it is a standalone input that only stores the entity
+// id for the device's own automations. Its key is the FNV-1 hash
+// of the input's ESPHome id, not an entity key. The client sends the chosen entity id to
+// the device with a WizardInputSetRequest. entity_filters says which Home Assistant
+// entities the user may choose, and mirrors Home Assistant's EntityFilterSelectorConfig:
+// an entity matches a filter when it satisfies every field that is set, and an entity
+// that matches any one of the filters is accepted.
+//
+// An input with "multiple": true lets the user pick several entities. The client sends
+// them in one WizardInputSetRequest as a comma separated list with no spaces
+// ("calendar.a,calendar.b"); the device also accepts spaces around each id and stores the
+// list without them. "max_length" (only on a multiple input, 255 when left out) is the
+// longest list in bytes the device accepts. The version stays 1: a client that does not
+// know "multiple" ignores it, shows a single picker and sends one entity id, which a
+// multiple input accepts.
+//
+// The device keeps the entity id of an input in RAM only and does not store it across
+// restarts. The client therefore stores the choice itself and, after every connection
+// and before it sends SubscribeHomeAssistantStatesRequest, sends a WizardInputSetRequest
+// for each input. It sends one again whenever the user changes the choice.
+message DeviceWizardResponse {
+  option (id) = 157;
+  option (source) = SOURCE_SERVER;
+  option (ifdef) = "USE_API_WIZARD";
+
+  // The data is in flash, and the device sends it from there
+  bytes data = 1 [(pointer_to_buffer) = true, (progmem) = true];
+}
+
+// Sets the entity id of a wizard input (see WizardInputField.key). Clients send
+// this only when DeviceCapabilitiesResponse.wizard.configured is set. There is no
+// reply. The device ignores a request whose key matches no input. A single input is
+// ignored when the entity_id is empty, longer than 255 bytes or has no '.'. A multiple
+// input takes a comma separated list ("calendar.a,calendar.b"); the client sends no
+// spaces, the device trims spaces around each id and stores the list without them. The
+// whole request is ignored when any id is empty or has no '.', or when the list without
+// spaces does not fit the input's max_length (255 by default). Otherwise it keeps the id
+// or list in RAM,
+// not across restarts, and when the input belongs to a homeassistant platform entity
+// it subscribes to that entity's state. Clients send this for every input right
+// after connecting, before SubscribeHomeAssistantStatesRequest. A request that
+// arrives later still works: the device then sends the affected state subscriptions
+// again.
+message WizardInputSetRequest {
+  option (id) = 158;
+  option (source) = SOURCE_CLIENT;
+  option (ifdef) = "USE_API_WIZARD_INPUTS";
+
+  fixed32 key = 1;
+  string entity_id = 2 [(max_data_length) = 4095];
 }

 message ListEntitiesRequest {
@@ -1439,7 +1560,7 @@ message ListEntitiesSelectResponse {
  reserved 4; // Deprecated: was string unique_id

  string icon = 5 [(field_ifdef) = "USE_ENTITY_ICON", (max_data_length) = 63];
-  repeated string options = 6 [(container_pointer_no_template) = "FixedVector<const char *>"];
+  repeated string options = 6 [(container_pointer_no_template) = "std::span<const char *const>"];
  bool disabled_by_default = 7;
  EntityCategory entity_category = 8;
  uint32 device_id = 9 [(field_ifdef) = "USE_DEVICES"];
@@ -2683,7 +2804,7 @@ message ListEntitiesInfraredResponse {
 message InfraredRFTransmitRawTimingsRequest {
  option (id) = 136;
  option (source) = SOURCE_CLIENT;
-  option (ifdef) = "USE_IR_RF || USE_RADIO_FREQUENCY";
+  option (ifdef) = "USE_IR_RF";

  uint32 device_id = 1 [(field_ifdef) = "USE_DEVICES"];
  fixed32 key = 2 [(force) = true];     // Key identifying the transmitter instance
@@ -2697,7 +2818,7 @@ message InfraredRFTransmitRawTimingsRequest {
 message InfraredRFReceiveEvent {
  option (id) = 137;
  option (source) = SOURCE_SERVER;
-  option (ifdef) = "USE_IR_RF || USE_RADIO_FREQUENCY";
+  option (ifdef) = "USE_IR_RF";
  option (no_delay) = true;
  option (speed_optimized) = true;

@@ -2706,6 +2827,28 @@ message InfraredRFReceiveEvent {
  repeated sint32 timings = 3 [packed = true, (container_pointer_no_template) = "std::vector<int32_t>"];  // Raw timings in microseconds (zigzag-encoded): alternating mark/space periods
 }

+// Sent only to the client that issued an InfraredRFTransmitRawTimingsRequest, once the
+// transmitter reports that the transmission (all repeats) has finished, or immediately with
+// success=false if it was refused before reaching the transmitter (unknown key, no transmitter,
+// no or invalid timings) or the transmitter could not send it (not set up, hardware error).
+// success=false also answers a request superseded by a newer request on the same entity, from
+// any client, and a transmit that reported nothing within 30 s past its expected air time, so a
+// client should not retry on it blindly. The device serializes transmits per transmitter and
+// several entities may share one, so a client should keep at most one transmit outstanding per
+// device, not per entity. A reply for an unknown key or a refused request is sent once and can be lost
+// when the device's send buffer is full, so a client should also stop waiting on its own after the
+// expected air time plus a margin. Lets clients pace requests instead of estimating durations (since API 1.18)
+message InfraredRFTransmitCompleteResponse {
+  option (id) = 153;
+  option (source) = SOURCE_SERVER;
+  option (ifdef) = "USE_IR_RF";
+  option (no_delay) = true;
+
+  uint32 device_id = 1 [(field_ifdef) = "USE_DEVICES"];
+  fixed32 key = 2 [(force) = true];  // Key of the transmitter entity from the request
+  bool success = 3;                  // false if the request was refused, not sent, superseded, or never reported
+}
+
 // ==================== RADIO FREQUENCY ====================

 // Lists available radio frequency entity instances
@@ -2876,6 +3019,56 @@ message SerialProxySetModeRequest {
  SerialProxyMode mode = 2;
 }

+// Subscribe to the identity of every serial proxy port. The device answers with one
+// SerialProxyIdentity per port, then sends another whenever a port's identity changes,
+// for the life of the connection (since API 1.18).
+message SubscribeSerialProxyIdentityRequest {
+  option (id) = 154;
+  option (source) = SOURCE_CLIENT;
+  option (ifdef) = "USE_SERIAL_PROXY";
+}
+
+// Where a port's identity comes from
+enum SerialProxyIdentitySource {
+  SERIAL_PROXY_IDENTITY_SOURCE_NONE = 0;        // The port carries no identity
+  SERIAL_PROXY_IDENTITY_SOURCE_CONFIGURED = 1;  // Reserved for identities stated in the device configuration; not sent yet
+  SERIAL_PROXY_IDENTITY_SOURCE_USB = 2;         // Read from the descriptors of the USB device behind the port;
+                                                // changes when a device is attached or removed
+}
+
+enum SerialProxyIdentityFlag {
+  SERIAL_PROXY_IDENTITY_FLAG_NONE = 0;
+  SERIAL_PROXY_IDENTITY_FLAG_CONNECTED = 1;  // The backend believes the device is present and usable on this port
+  SERIAL_PROXY_IDENTITY_FLAG_ERROR = 2;      // The USB host stack refused the descriptor query; the strings and
+                                             // IDs below are empty
+}
+
+// The descriptor fields of a USB device as seen by the host stack
+message UsbDeviceDescriptor {
+  uint32 vendor_id = 1;
+  uint32 product_id = 2;
+  uint32 bcd_device = 3;
+  uint32 interface_number = 4;   // bInterfaceNumber the host driver binds to
+}
+
+// The identity of the device behind a port. Identifies one physical device among others of
+// the same kind, so a client matches on manufacturer and product regardless of source. The
+// strings are empty for source NONE, and for source USB while nothing is connected
+// (since API 1.18).
+message SerialProxyIdentity {
+  option (id) = 155;
+  option (source) = SOURCE_SERVER;
+  option (ifdef) = "USE_SERIAL_PROXY";
+
+  uint32 instance = 1;
+  SerialProxyIdentitySource source = 2;
+  uint32 flags = 3;               // Bitmask of SerialProxyIdentityFlag
+  string manufacturer = 4;
+  string product = 5;
+  string serial_number = 6;
+  UsbDeviceDescriptor usb = 7;    // Only sent for source USB
+}
+
 // ==================== BLUETOOTH CONNECTION PARAMS ====================
 message BluetoothSetConnectionParamsRequest {
  option (id) = 145;
@@ -2897,3 +3090,34 @@ message BluetoothSetConnectionParamsResponse {
  uint64 address = 1;
  int32 error = 2;
 }
+
+// ==================== SENDSPIN ====================
+enum SendspinPairingTokenStatus {
+  // The Sendspin client has not started yet, so the token does not exist yet. Ask again later.
+  SENDSPIN_PAIRING_TOKEN_STATUS_NOT_READY = 0;
+  SENDSPIN_PAIRING_TOKEN_STATUS_OK = 1;
+  // The device has no API encryption key, so it will not send the token. Ask again once a key is set.
+  SENDSPIN_PAIRING_TOKEN_STATUS_ENCRYPTION_REQUIRED = 2;
+  // Sendspin is turned off and has not started since boot, so the token does not exist yet.
+  SENDSPIN_PAIRING_TOKEN_STATUS_DISABLED = 3;
+  // The Sendspin client failed to start, and will not start until the device reboots.
+  SENDSPIN_PAIRING_TOKEN_STATUS_FAILED = 4;
+}
+
+// Requests the Sendspin pairing token, which a Sendspin server uses to pair with this device
+message SendspinPairingTokenRequest {
+  option (id) = 159;
+  option (source) = SOURCE_CLIENT;
+  option (ifdef) = "USE_SENDSPIN";
+  // Empty
+}
+
+message SendspinPairingTokenResponse {
+  option (id) = 160;
+  option (source) = SOURCE_SERVER;
+  option (ifdef) = "USE_SENDSPIN";
+
+  SendspinPairingTokenStatus status = 1;
+  // The pairing token (Sendspin pairing.md "Pairing Token"). Set only when status is OK.
+  string token = 2 [(max_data_length) = 127];
+}
@@ -48,6 +48,9 @@
 #ifdef USE_ZWAVE_PROXY
 #include "esphome/components/zwave_proxy/zwave_proxy.h"
 #endif
+#if defined(USE_SENDSPIN) && defined(USE_ESP_IDF)
+#include "esphome/components/sendspin/sendspin_hub.h"
+#endif
 #ifdef USE_WATER_HEATER
 #include "esphome/components/water_heater/water_heater.h"
 #endif
@@ -198,6 +201,17 @@ APIConnection::~APIConnection() {
      proxy->serial_proxy_request(this, enums::SERIAL_PROXY_REQUEST_TYPE_UNSUBSCRIBE);
    }
  }
+#endif
+  // entities holding a transmit reply for this client must not answer into a freed connection
+#ifdef USE_INFRARED
+  for (auto *infrared : App.get_infrareds()) {
+    infrared->on_api_connection_closed(this);
+  }
+#endif
+#ifdef USE_RADIO_FREQUENCY
+  for (auto *radio_frequency : App.get_radio_frequencies()) {
+    radio_frequency->on_api_connection_closed(this);
+  }
 #endif
 }

@@ -990,7 +1004,9 @@ uint16_t APIConnection::try_send_select_state(EntityBase *entity, APIConnection
 uint16_t APIConnection::try_send_select_info(EntityBase *entity, APIConnection *conn, uint32_t remaining_size) {
  auto *select = static_cast<select::Select *>(entity);
  ListEntitiesSelectResponse msg;
-  msg.options = &select->traits.get_options();
+  const auto &opts = select->traits.get_options();
+  const std::span<const char *const> options(opts.data(), opts.size());
+  msg.options = &options;
  return fill_and_encode_entity_info(select, msg, conn, remaining_size);
 }
 void APIConnection::on_select_command_request(const SelectCommandRequest &msg) {
@@ -1389,6 +1405,40 @@ void APIConnection::on_z_wave_proxy_request(const ZWaveProxyRequest &msg) {
 }
 #endif

+#if defined(USE_SENDSPIN) && defined(USE_ESP_IDF)
+bool APIConnection::send_sendspin_pairing_token_response_() {
+  SendspinPairingTokenResponse resp;
+#ifdef USE_API_NOISE
+  // has_psk() stands in for "this session proved the key": with a key active, plaintext and zero-key sessions
+  // never reach hello, and activating a key closes every session opened before it.
+  if (!this->parent_->get_noise_ctx().has_psk()) {
+    resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_ENCRYPTION_REQUIRED;
+    return this->send_message(resp);
+  }
+  auto token = sendspin_::global_sendspin_hub->get_pairing_token();
+  if (token.has_value()) {
+    resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_OK;
+    resp.token = StringRef(*token);
+  } else if (sendspin_::global_sendspin_hub->status_has_error()) {
+    resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_FAILED;
+  } else if (sendspin_::global_sendspin_hub->is_disabled()) {
+    resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_DISABLED;
+  } else {
+    resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_NOT_READY;
+  }
+#else
+  resp.status = enums::SENDSPIN_PAIRING_TOKEN_STATUS_ENCRYPTION_REQUIRED;
+#endif
+  return this->send_message(resp);
+}
+
+void APIConnection::on_sendspin_pairing_token_request() {
+  if (!this->send_sendspin_pairing_token_response_()) {
+    this->on_fatal_error();
+  }
+}
+#endif
+
 #ifdef USE_ALARM_CONTROL_PANEL
 bool APIConnection::send_alarm_control_panel_state(alarm_control_panel::AlarmControlPanel *a_alarm_control_panel) {
  return this->send_message_smart_(a_alarm_control_panel, AlarmControlPanelStateResponse::MESSAGE_TYPE,
@@ -1515,8 +1565,10 @@ uint16_t APIConnection::try_send_event_info(EntityBase *entity, APIConnection *c
 }
 #endif

-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
 void APIConnection::on_infrared_rf_transmit_raw_timings_request(const InfraredRFTransmitRawTimingsRequest &msg) {
+  // Clients on API 1.18+ are told when the frame has left the transmitter; the entity owns that reply
+  const bool want_reply = this->client_supports_api_version(1, 18);
  // Dispatch by key: infrared entities are checked first, then radio frequency entities.
  // The key is unique across all entity instances on a device, so at most one lookup will succeed.
 #ifdef USE_INFRARED
@@ -1526,6 +1578,7 @@ void APIConnection::on_infrared_rf_transmit_raw_timings_request(const InfraredRF
    call.set_carrier_frequency(msg.carrier_frequency);
    call.set_raw_timings_packed(msg.timings_data_, msg.timings_length_, msg.timings_count_);
    call.set_repeat_count(msg.repeat_count);
+    call.set_api_connection(want_reply ? this : nullptr);
    call.perform();
    return;
  }
@@ -1538,13 +1591,38 @@ void APIConnection::on_infrared_rf_transmit_raw_timings_request(const InfraredRF
    call.set_modulation(static_cast<radio_frequency::RadioFrequencyModulation>(msg.modulation));
    call.set_repeat_count(msg.repeat_count);
    call.set_raw_timings_packed(msg.timings_data_, msg.timings_length_, msg.timings_count_);
+    call.set_api_connection(want_reply ? this : nullptr);
    call.perform();
+    return;
  }
 #endif
+  ESP_LOGW(TAG, "IR/RF transmit for unknown key %" PRIu32, msg.key);
+  if (want_reply) {
+    // nothing will ever report for an unknown key, so answer as not started right away
+#ifdef USE_DEVICES
+    const uint32_t device_id = msg.device_id;
+#else
+    const uint32_t device_id = 0;
+#endif
+    if (!this->send_infrared_rf_transmit_complete(device_id, msg.key, false)) {
+      API_LOG_MSG_DROPPED(TAG, "IR/RF reply");
+    }
+  }
+}
+
+bool APIConnection::send_infrared_rf_transmit_complete([[maybe_unused]] uint32_t device_id, uint32_t key,
+                                                       bool success) {
+  InfraredRFTransmitCompleteResponse resp{};
+#ifdef USE_DEVICES
+  resp.device_id = device_id;
+#endif
+  resp.key = key;
+  resp.success = success;
+  return this->send_message(resp);
 }
 #endif

-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
 void APIConnection::send_infrared_rf_receive_event(const InfraredRFReceiveEvent &msg) {
  if (!this->send_message(msg)) {
    // V: fires per decoded frame with no subscription gate, so a warning
@@ -1552,6 +1630,7 @@ void APIConnection::send_infrared_rf_receive_event(const InfraredRFReceiveEvent
    ESP_LOGV(TAG, "IR/RF event dropped, TCP buffer full");
  }
 }
+
 #endif

 #ifdef USE_SERIAL_PROXY
@@ -1643,6 +1722,22 @@ void APIConnection::on_serial_proxy_get_modem_pins_request(const SerialProxyGetM
  }
 }

+void APIConnection::on_subscribe_serial_proxy_identity_request() {
+#ifdef USE_SERIAL_PROXY_USB_IDENTITY
+  // Only USB ports change identity after this snapshot
+  this->flags_.serial_proxy_identity_subscription = true;
+#endif
+  for (auto *proxy : App.get_serial_proxies()) {
+    proxy->send_identity(this);
+  }
+}
+
+void APIConnection::send_serial_proxy_identity(const SerialProxyIdentity &msg) {
+  if (!this->send_message(msg)) {
+    API_LOG_MSG_DROPPED(TAG, "Serial proxy identity");
+  }
+}
+
 void APIConnection::on_serial_proxy_request(const SerialProxyRequest &msg) {
  auto &proxies = App.get_serial_proxies();
  if (msg.instance >= proxies.size()) {
@@ -1814,7 +1909,7 @@ bool APIConnection::send_hello_response_(const HelloRequest &msg) {

  HelloResponse resp;
  resp.api_version_major = 1;
-  resp.api_version_minor = 17;
+  resp.api_version_minor = 19;
  // Send only the version string - the client only logs this for debugging and doesn't use it otherwise
  resp.server_info = ESPHOME_VERSION_REF;
  resp.name = StringRef(App.get_name());
@@ -1837,6 +1932,19 @@ bool APIConnection::send_hello_response_(const HelloRequest &msg) {
  // Auto-authenticate - password auth was removed in ESPHome 2026.1.0
  this->complete_authentication_();

+#ifdef USE_API_OUTGOING_CONNECTION
+  // With a PSK set only key-verified transports reach hello: plaintext and
+  // zero-PSK are rejected, and pre-activation sessions are force-closed
+  if (msg.outgoing_connection_target && !this->flags_.outgoing_connection_target) {
+    if (this->parent_->get_noise_ctx().has_psk()) {
+      this->flags_.outgoing_connection_target = true;
+      this->parent_->on_outgoing_target_client(this);
+    } else {
+      this->log_client_(ESPHOME_LOG_LEVEL_WARN, LOG_STR("Dial-back target refused; no key active"));
+    }
+  }
+#endif
+
  return this->send_message(resp);
 }

@@ -1959,6 +2067,9 @@ bool APIConnection::send_device_info_response_() {
  // one) so this advertisement survives the plaintext removal in 2027.2.0.
  resp.api_encryption_provisionable = !this->parent_->get_noise_ctx().has_psk();
 #endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  resp.api_outgoing_connection_supported = true;
+#endif
 #endif
 #ifdef USE_DEVICES
  size_t device_index = 0;
@@ -2011,6 +2122,12 @@ bool APIConnection::send_device_capabilities_response_() {
    info.port_type = proxy->get_port_type();
    info.configured_line_states = proxy->get_configured_modem_pins();
  }
+#endif
+#ifdef USE_API_WIZARD
+  resp.wizard.configured = true;
+#endif
+#if defined(USE_SENDSPIN) && defined(USE_ESP_IDF)
+  resp.sendspin.feature_flags = sendspin_::global_sendspin_hub->get_feature_flags();
 #endif
  return this->send_message(resp);
 }
@@ -2225,7 +2342,13 @@ void APIConnection::on_noise_encryption_set_key_request(const NoiseEncryptionSet
 }
 #endif
 #ifdef USE_API_HOMEASSISTANT_STATES
-void APIConnection::on_subscribe_home_assistant_states_request() { state_subs_at_ = 0; }
+void APIConnection::on_subscribe_home_assistant_states_request() {
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+  // Remember it, as a client that subscribed also gets the subscriptions again when a wizard input is set
+  this->flags_.home_assistant_states = true;
+#endif
+  state_subs_at_ = 0;
+}
 #endif
 bool APIConnection::try_to_clear_buffer_slow_(bool log_out_of_space) {
  delay(0);
@@ -2269,8 +2392,7 @@ bool APIConnection::send_message_(uint32_t payload_size, uint16_t message_type,
 #endif
  // Capacity reserved above, cannot fail
  (void) shared_buf.resize(write_start + payload_size);
-  ProtoWriteBuffer buffer{&shared_buf, write_start};
-  uint8_t *end = encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+  uint8_t *end = encode_fn(msg, shared_buf.data() + write_start PROTO_ENCODE_DEBUG_INIT(&shared_buf));
 #ifdef ESPHOME_DEBUG_API
  proto_check_encode_end(end, shared_buf.data() + shared_buf.size());
 #else
@@ -2668,6 +2790,13 @@ void APIConnection::process_state_subscriptions_() {
  }

  const auto &it = subs[this->state_subs_at_];
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+  // An entity id that is not set yet (a wizard input) has nothing to subscribe to; it is sent once it is set
+  if (it.entity_id[0] == '\0') {
+    this->state_subs_at_++;
+    return;
+  }
+#endif
  SubscribeHomeAssistantStateResponse resp;
  resp.entity_id = StringRef(it.entity_id);

@@ -223,6 +223,10 @@ class APIConnection final : public APIServerConnectionBase {
  void on_z_wave_proxy_request(const ZWaveProxyRequest &msg);
 #endif

+#if defined(USE_SENDSPIN) && defined(USE_ESP_IDF)
+  void on_sendspin_pairing_token_request();
+#endif
+
 #ifdef USE_ALARM_CONTROL_PANEL
  bool send_alarm_control_panel_state(alarm_control_panel::AlarmControlPanel *a_alarm_control_panel);
  void on_alarm_control_panel_command_request(const AlarmControlPanelCommandRequest &msg);
@@ -233,9 +237,12 @@ class APIConnection final : public APIServerConnectionBase {
  void on_water_heater_command_request(const WaterHeaterCommandRequest &msg);
 #endif

-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
  void on_infrared_rf_transmit_raw_timings_request(const InfraredRFTransmitRawTimingsRequest &msg);
  void send_infrared_rf_receive_event(const InfraredRFReceiveEvent &msg);
+  // Reply to an InfraredRFTransmitRawTimingsRequest (API 1.18+); false when the TCP buffer is
+  // full, the entity that owns the reply retries it then
+  [[nodiscard]] bool send_infrared_rf_transmit_complete(uint32_t device_id, uint32_t key, bool success);
 #endif

 #ifdef USE_SERIAL_PROXY
@@ -243,6 +250,9 @@ class APIConnection final : public APIServerConnectionBase {
  void on_serial_proxy_write_request(const SerialProxyWriteRequest &msg);
  void on_serial_proxy_set_modem_pins_request(const SerialProxySetModemPinsRequest &msg);
  void on_serial_proxy_get_modem_pins_request(const SerialProxyGetModemPinsRequest &msg);
+  void on_subscribe_serial_proxy_identity_request();
+  /// Send a port identity to this client
+  void send_serial_proxy_identity(const SerialProxyIdentity &msg);
  void on_serial_proxy_request(const SerialProxyRequest &msg);
  void on_serial_proxy_set_mode_request(const SerialProxySetModeRequest &msg);
  void send_serial_proxy_data(const SerialProxyDataReceived &msg);
@@ -273,6 +283,12 @@ class APIConnection final : public APIServerConnectionBase {
  void on_ping_request();
  void on_device_info_request();
  void on_device_capabilities_request();
+#ifdef USE_API_WIZARD
+  void on_device_wizard_request();
+#endif
+#ifdef USE_API_WIZARD_INPUTS
+  void on_wizard_input_set_request(const WizardInputSetRequest &msg);
+#endif
  void on_list_entities_request() { this->begin_iterator_(ActiveIterator::LIST_ENTITIES); }
  void on_subscribe_states_request() {
    this->flags_.state_subscription = true;
@@ -302,6 +318,10 @@ class APIConnection final : public APIServerConnectionBase {
 #endif
 #ifdef USE_API_HOMEASSISTANT_STATES
  void on_subscribe_home_assistant_states_request();
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+  /// Tell this client about the subscriptions whose entity id is stored in the given buffer, as the buffer changed
+  void resend_state_subscriptions(const char *entity_id);
+#endif
 #endif
 #ifdef USE_API_USER_DEFINED_ACTIONS
  void on_execute_service_request(const ExecuteServiceRequest &msg);
@@ -317,9 +337,15 @@ 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();
@@ -339,7 +365,7 @@ class APIConnection final : public APIServerConnectionBase {
  void on_no_setup_connection();

  // Function pointer type for type-erased message encoding
-  using MessageEncodeFn = uint8_t *(*) (const void *, ProtoWriteBuffer &PROTO_ENCODE_DEBUG_PARAM);
+  using MessageEncodeFn = ProtoEncodeFn;
  // Function pointer type for type-erased size calculation
  using CalculateSizeFn = uint32_t (*)(const void *);

@@ -372,6 +398,23 @@ class APIConnection final : public APIServerConnectionBase {
    return this->helper_->get_peername_to(buf);
  }

+#ifdef USE_API_OUTGOING_CONNECTION
+  /// Get the peer address itself, for remembering a dial-back target
+  int getpeername(struct sockaddr *addr, socklen_t *addrlen) const { return this->helper_->getpeername(addr, addrlen); }
+  /// Outgoing connection: send our server hello immediately so the peer can
+  /// pick the matching key. Outgoing connections are only dialed when a PSK
+  /// is set, so the helper is always the noise helper. Call after start().
+  void mark_outgoing() {
+    if (this->flags_.remove) {
+      return;  // start() failed; the connection is already being torn down
+    }
+    APIError err = static_cast<APINoiseFrameHelper *>(this->helper_.get())->send_server_hello_first();
+    if (err != APIError::OK) {
+      this->fatal_error_with_log_(LOG_STR("Server hello failed"), err);
+    }
+  }
+#endif
+
 protected:
  bool try_to_clear_buffer_slow_(bool log_out_of_space);

@@ -393,6 +436,9 @@ class APIConnection final : public APIServerConnectionBase {
 #ifdef USE_VOICE_ASSISTANT
  bool send_voice_assistant_get_configuration_response_(const VoiceAssistantConfigurationRequest &msg);
 #endif
+#if defined(USE_SENDSPIN) && defined(USE_ESP_IDF)
+  bool send_sendspin_pairing_token_response_();
+#endif

 #ifdef USE_CAMERA
  void try_send_camera_image_();
@@ -728,12 +774,21 @@ class APIConnection final : public APIServerConnectionBase {
    uint8_t batch_first_message : 1;          // For batch buffer allocation
    uint8_t should_try_send_immediately : 1;  // True after initial states are sent
    uint8_t may_have_remaining_data : 1;      // Read loop hit limit, retry without ready check
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+    uint8_t home_assistant_states : 1;  // Client subscribed to Home Assistant states
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+    uint8_t outgoing_connection_target : 1;  // Client declared itself a dial-back target in its hello
+#endif
 #ifdef HAS_PROTO_MESSAGE_DUMP
    uint8_t log_only_mode : 1;
 #endif
-  } flags_{};  // 2 bytes total
+#ifdef USE_SERIAL_PROXY_USB_IDENTITY
+    uint8_t serial_proxy_identity_subscription : 1;
+#endif
+  } flags_{};  // 2 bytes; 3 with HAS_PROTO_MESSAGE_DUMP + USE_API_OUTGOING_CONNECTION + USE_SERIAL_PROXY_USB_IDENTITY

-  // 2-byte type immediately after flags_ (no padding between them)
+  // 2-byte type immediately after flags_ (one padding byte when flags_ is 3 bytes)
  uint16_t batch_message_type_{0};  // Current message type during batch encoding
  // 1-byte types to fill remaining space before next 4-byte boundary
  // Client API versions are clamped to 255 on receive (see send_hello_response_)
@@ -45,8 +45,8 @@ inline uint16_t ESPHOME_ALWAYS_INLINE APIConnection::encode_to_buffer(uint32_t c
    conn->fatal_out_of_memory_();
    return 0;
  }
-  ProtoWriteBuffer buffer{&shared_buf, shared_buf.size() - calculated_size};
-  uint8_t *end = encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+  uint8_t *end =
+      encode_fn(msg, shared_buf.data() + shared_buf.size() - calculated_size PROTO_ENCODE_DEBUG_INIT(&shared_buf));
 #ifdef ESPHOME_DEBUG_API
  // A body that writes fewer bytes than calculate_size() promised would ship stale buffer bytes
  proto_check_encode_end(end, shared_buf.data() + shared_buf.size());
@@ -285,7 +285,8 @@ class APIFrameHelper {
    DATA = 5,
    CLOSED = 6,
    FAILED = 7,
-    EXPLICIT_REJECT = 8,  // Noise only
+    EXPLICIT_REJECT = 8,        // Noise only
+    CLIENT_HELLO_OUTGOING = 9,  // Noise only: like CLIENT_HELLO but the server hello already went out (outgoing conn)
  };

  // Fast inline state check for read_packet/write_protobuf_messages hot path.
@@ -70,6 +70,13 @@ APIError APINoiseFrameHelper::init() {
  state_ = State::CLIENT_HELLO;
  return APIError::OK;
 }
+#ifdef USE_API_OUTGOING_CONNECTION
+APIError APINoiseFrameHelper::send_server_hello_first() {
+  // The peer needs our name and MAC to pick the key before its first message
+  this->state_ = State::CLIENT_HELLO_OUTGOING;
+  return this->send_server_hello_frame_();
+}
+#endif
 #ifdef USE_API_PLAINTEXT
 APIError APINoiseFrameHelper::init_from_handoff(const uint8_t *header, uint8_t header_len) {
  APIError err = this->init();
@@ -242,6 +249,9 @@ APIError APINoiseFrameHelper::state_action_() {
      HELPER_LOG("Bad state for method: %d", (int) this->state_);
      return APIError::BAD_STATE;
    case State::CLIENT_HELLO:
+#ifdef USE_API_OUTGOING_CONNECTION
+    case State::CLIENT_HELLO_OUTGOING:
+#endif
      return this->state_action_client_hello_();
    case State::SERVER_HELLO:
      return this->state_action_server_hello_();
@@ -274,11 +284,16 @@ APIError APINoiseFrameHelper::state_action_client_hello_() {
    std::memcpy(dst + 2, this->rx_buf_.data(), rx_size);
  }

+#ifdef USE_API_OUTGOING_CONNECTION
+  if (this->state_ == State::CLIENT_HELLO_OUTGOING) {
+    // Server hello already went out at handoff
+    return this->start_handshake_();
+  }
+#endif
  state_ = State::SERVER_HELLO;
  return APIError::OK;
 }
-APIError APINoiseFrameHelper::state_action_server_hello_() {
-  // send server hello
+APIError APINoiseFrameHelper::send_server_hello_frame_() {
  const auto &name = App.get_name();
  char mac[MAC_ADDRESS_BUFFER_SIZE];
  get_mac_address_into_buffer(mac);
@@ -302,15 +317,18 @@ APIError APINoiseFrameHelper::state_action_server_hello_() {
  // node mac, terminated by null byte
  std::memcpy(msg + mac_offset, mac, MAC_ADDRESS_BUFFER_SIZE);

-  APIError aerr = write_frame_(msg, total_size);
+  return write_frame_(msg, total_size);
+}
+APIError APINoiseFrameHelper::state_action_server_hello_() {
+  APIError aerr = this->send_server_hello_frame_();
  if (aerr != APIError::OK)
    return aerr;
-
-  // start handshake
-  aerr = init_handshake_();
+  return this->start_handshake_();
+}
+APIError APINoiseFrameHelper::start_handshake_() {
+  APIError aerr = init_handshake_();
  if (aerr != APIError::OK)
    return aerr;
-
  state_ = State::HANDSHAKE;
  return APIError::OK;
 }
@@ -28,6 +28,12 @@ class APINoiseFrameHelper final : public APIFrameHelper {
  // Seeds the already-read header bytes and pumps the handshake state machine
  // until it would block.
  APIError init_from_handoff(const uint8_t *header, uint8_t header_len);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Send the server hello immediately so the peer can pick the key before
+  // its PSK-mixed message. Call after init(); the mode is tracked in state_
+  // so the helper does not grow.
+  APIError send_server_hello_first();
 #endif
  APIError loop() override;
  APIError read_packet(ReadPacketBuffer *buffer) override;
@@ -39,6 +45,8 @@ class APINoiseFrameHelper final : public APIFrameHelper {
  APIError state_action_();
  APIError state_action_client_hello_();
  APIError state_action_server_hello_();
+  APIError send_server_hello_frame_();
+  APIError start_handshake_();
  APIError state_action_handshake_();
  APIError state_action_handshake_read_();
  APIError state_action_handshake_write_();
@@ -122,4 +122,9 @@ extend google.protobuf.FieldOptions {
    // to true when the field arrives, so an all-default submessage can be told apart
    // from an absent one (e.g. a UTC ParsedTimezone, which is all zeros).
    optional bool track_presence = 50020 [default=false];
+
+    // progmem: The pointer_to_buffer bytes field points into flash (PROGMEM).
+    // The generated encode and dump copy it with progmem_memcpy, as ESP8266
+    // cannot read flash with ordinary loads.
+    optional bool progmem = 50021 [default=false];
 }
@@ -0,0 +1,318 @@
+#include "api_outgoing_connection.h"
+#if defined(USE_API) && defined(USE_API_OUTGOING_CONNECTION)
+
+#include "api_connection.h"
+#include "api_server.h"
+#include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+#include <cerrno>
+#include <cinttypes>
+#include <cstdint>
+#include <cstring>
+
+namespace esphome::api {
+
+static const char *const TAG = "api.outgoing";
+
+#ifndef API_OUTGOING_CONNECTION_HOST
+static constexpr uint32_t OUTGOING_TARGET_PREF_HASH = 629847102UL;
+#endif
+
+#ifndef API_OUTGOING_CONNECTION_HOST
+// Read the connection's peer address into target; false when unavailable or
+// of a family this build cannot dial
+static bool peer_to_target(APIConnection *conn, SavedOutgoingTarget &target) {
+  // Zeroed because the raw lwIP getpeername() leaves sin6_scope_id untouched
+  struct sockaddr_storage peer = {};
+  socklen_t peer_len = sizeof(peer);
+  if (conn->getpeername((struct sockaddr *) &peer, &peer_len) != 0) {
+    return false;
+  }
+  const sa_family_t family = ((struct sockaddr *) &peer)->sa_family;
+#if USE_NETWORK_IPV6
+  if (family == AF_INET6) {
+    const auto *addr6 = reinterpret_cast<const struct sockaddr_in6 *>(&peer);
+    const auto *bytes = reinterpret_cast<const uint8_t *>(&addr6->sin6_addr);
+    uint32_t prefix[3];
+    memcpy(prefix, bytes, sizeof(prefix));
+    // A dual-stack listener reports an IPv4 peer as ::ffff:a.b.c.d
+    if (prefix[0] == 0 && prefix[1] == 0 && prefix[2] == htonl(0xFFFFUL)) {
+      target.family = AF_INET;
+      memcpy(target.addr, bytes + sizeof(prefix), sizeof(struct in_addr));
+      return true;
+    }
+    // A link-local target is only reachable through the interface it came in
+    // on. Device platforms number interfaces from one; a host build can hand
+    // out an index too large to store, and a truncated one dials the wrong
+    // interface, so that target is not remembered at all.
+    if (addr6->sin6_scope_id > UINT8_MAX) {
+      return false;
+    }
+    target.family = AF_INET6;
+    memcpy(target.addr, bytes, sizeof(target.addr));
+    target.scope_id = static_cast<uint8_t>(addr6->sin6_scope_id);
+    return true;
+  }
+#endif
+  if (family != AF_INET) {
+    return false;
+  }
+  const auto *addr4 = reinterpret_cast<const struct sockaddr_in *>(&peer);
+  target.family = AF_INET;
+  memcpy(target.addr, &addr4->sin_addr, sizeof(addr4->sin_addr));
+  return true;
+}
+#endif
+
+socklen_t OutgoingConnectionManager::target_sockaddr_(struct sockaddr_storage *addr) const {
+#ifdef API_OUTGOING_CONNECTION_HOST
+  // Validation only lets through a literal both inet_pton and inet6_aton
+  // accept, so this cannot fail
+  return socket::set_sockaddr((struct sockaddr *) addr, sizeof(*addr), API_OUTGOING_CONNECTION_HOST,
+                              API_OUTGOING_CONNECTION_PORT);
+#else
+#if USE_NETWORK_IPV6
+  if (this->saved_.family == AF_INET6) {
+    auto *addr6 = reinterpret_cast<struct sockaddr_in6 *>(addr);
+    memset(addr6, 0, sizeof(*addr6));
+    addr6->sin6_family = AF_INET6;
+    addr6->sin6_port = htons(API_OUTGOING_CONNECTION_PORT);
+    memcpy(&addr6->sin6_addr, this->saved_.addr, sizeof(this->saved_.addr));
+    addr6->sin6_scope_id = this->saved_.scope_id;
+    return sizeof(*addr6);
+  }
+#endif
+  if (this->saved_.family != AF_INET) {
+    return 0;
+  }
+  auto *addr4 = reinterpret_cast<struct sockaddr_in *>(addr);
+  memset(addr4, 0, sizeof(*addr4));
+  addr4->sin_family = AF_INET;
+  addr4->sin_port = htons(API_OUTGOING_CONNECTION_PORT);
+  memcpy(&addr4->sin_addr, this->saved_.addr, sizeof(addr4->sin_addr));
+  return sizeof(*addr4);
+#endif
+}
+
+#ifndef API_OUTGOING_CONNECTION_HOST
+void OutgoingConnectionManager::format_target_(std::span<char, socket::SOCKADDR_STR_LEN> buf) const {
+  struct sockaddr_storage addr;
+  socklen_t addr_len = this->target_sockaddr_(&addr);
+  if (addr_len == 0) {
+    buf[0] = '\0';
+    return;
+  }
+  // Clears buf itself if it cannot format the address
+  socket::format_sockaddr_to((struct sockaddr *) &addr, addr_len, buf);
+}
+#endif
+
+void OutgoingConnectionManager::setup() {
+#ifndef API_OUTGOING_CONNECTION_HOST
+  this->target_pref_ = global_preferences->make_preference<SavedOutgoingTarget>(OUTGOING_TARGET_PREF_HASH, true);
+  struct sockaddr_storage addr;
+  // dump_config() prints whichever target this leaves in place
+  if (this->target_pref_.load(&this->saved_) && this->target_sockaddr_(&addr) != 0) {
+    this->host_persisted_ = true;
+  } else {
+    // Never saved, failed its size or CRC check, or holds an unknown family
+    this->saved_ = {};
+  }
+#endif
+}
+
+void OutgoingConnectionManager::loop(APIServer *server) {
+  if (server->has_outgoing_target_client_()) {
+    return;  // on_target_client() already reset the dial state
+  }
+  if (this->dialed_conn_ != nullptr) {
+    // A live dialed session (flagged or not, e.g. a host: peer) is the
+    // target; a silent one dies on the handshake timeout
+    return;
+  }
+  const uint32_t now = App.get_loop_component_start_time();
+  switch (this->state_) {
+    case DialState::DIAL_STATE_IDLE:
+      // Target went away; give it the configured delay to reconnect first
+      this->schedule_wait_(now, IDLE_WAIT_MS);
+      break;
+    case DialState::DIAL_STATE_WAITING:
+      if (now - this->state_ts_ >= this->wait_) {
+        this->try_dial_(server, now);
+      }
+      break;
+    case DialState::DIAL_STATE_CONNECTING:
+      this->poll_connect_(server, now);
+      break;
+  }
+}
+
+void OutgoingConnectionManager::try_dial_(APIServer *server, uint32_t now) {
+  if (!network::is_connected()) {
+    // Flips within seconds of boot; recheck fast so a deep sleep wake
+    // window is not spent waiting
+    this->schedule_wait_(now, NETWORK_RETRY_MS);
+    return;
+  }
+  struct sockaddr_storage addr;
+  socklen_t addr_len = this->target_sockaddr_(&addr);
+  const bool at_limit = server->at_client_limit_();
+  // No target is the steady state until a dial-back client has ever connected
+  if (addr_len == 0 || at_limit || !server->noise_ctx_.has_psk()) {
+    // Repeats for as long as the reason holds, so keep it out of debug logs
+    ESP_LOGV(TAG, "Not dialing: %s",
+             addr_len == 0 ? LOG_STR_LITERAL("no target")
+                           : (at_limit ? LOG_STR_LITERAL("max connections") : LOG_STR_LITERAL("no key")));
+    // Not a dial failure; retry without escalating the backoff
+    this->schedule_wait_(now, PRECONDITION_RETRY_MS);
+    return;
+  }
+  this->dial_socket_ = socket::socket_loop_monitored(((struct sockaddr *) &addr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
+  if (!this->dial_socket_ || this->dial_socket_->setblocking(false) != 0) {
+    ESP_LOGW(TAG, "Socket %s failed: errno %d",
+             this->dial_socket_ ? LOG_STR_LITERAL("setblocking") : LOG_STR_LITERAL("create"), errno);
+    this->schedule_retry_(now);
+    return;
+  }
+#ifdef API_OUTGOING_CONNECTION_HOST
+  ESP_LOGD(TAG, "Dialing " API_OUTGOING_CONNECTION_HOST ":%u", API_OUTGOING_CONNECTION_PORT);
+#else
+  char host[socket::SOCKADDR_STR_LEN];
+  socket::format_sockaddr_to((struct sockaddr *) &addr, addr_len, host);
+  ESP_LOGD(TAG, "Dialing %s:%u", host, API_OUTGOING_CONNECTION_PORT);
+#endif
+  int err = this->dial_socket_->connect((struct sockaddr *) &addr, addr_len);
+  if (err == 0) {
+    // Immediate success (possible for localhost)
+    this->handoff_(server, now);
+    return;
+  }
+  if (errno != EINPROGRESS) {
+    ESP_LOGW(TAG, "Connect failed: %d", errno);
+    this->schedule_retry_(now);
+    return;
+  }
+  this->state_ = DialState::DIAL_STATE_CONNECTING;
+  this->state_ts_ = now;
+  this->last_poll_ = now;
+}
+
+void OutgoingConnectionManager::poll_connect_(APIServer *server, uint32_t now) {
+  if (now - this->state_ts_ >= CONNECT_TIMEOUT_MS) {
+    ESP_LOGW(TAG, "Connect timeout");
+    this->schedule_retry_(now);
+    return;
+  }
+  if (now - this->last_poll_ < CONNECT_POLL_INTERVAL_MS) {
+    return;
+  }
+  this->last_poll_ = now;
+  int err = 0;
+  switch (socket::poll_connect(*this->dial_socket_, err)) {
+    case socket::ConnectPollResult::CONNECT_POLL_RESULT_PENDING:
+      break;
+    case socket::ConnectPollResult::CONNECT_POLL_RESULT_CONNECTED:
+      this->handoff_(server, now);
+      break;
+    case socket::ConnectPollResult::CONNECT_POLL_RESULT_ERROR:
+      ESP_LOGW(TAG, "Connect failed: %d", err);
+      this->schedule_retry_(now);
+      break;
+  }
+}
+
+void OutgoingConnectionManager::handoff_(APIServer *server, uint32_t now) {
+  this->dialed_conn_ = server->add_outgoing_client_(std::move(this->dial_socket_));
+  if (this->dialed_conn_ == nullptr) {
+    // Only preconditions (slot limit, key cleared) refuse the handoff; the
+    // peer is reachable, so do not escalate the backoff
+    this->schedule_wait_(now, PRECONDITION_RETRY_MS);
+    return;
+  }
+  // Connected; dialed_conn_ gates further dialing until the session settles
+  this->state_ = DialState::DIAL_STATE_IDLE;
+}
+
+void OutgoingConnectionManager::schedule_wait_(uint32_t now, uint32_t wait) {
+  this->dial_socket_.reset();  // no-op when the socket was handed off
+  this->state_ = DialState::DIAL_STATE_WAITING;
+  this->state_ts_ = now;
+  this->wait_ = wait;
+}
+
+void OutgoingConnectionManager::schedule_retry_(uint32_t now) {
+  // +/-20% jitter so a fleet of devices does not retry one server in lockstep
+  const uint32_t jitter_span = this->backoff_ / 5;
+  this->schedule_wait_(now, this->backoff_ - jitter_span + (random_uint32() % (2 * jitter_span + 1)));
+  this->backoff_ = std::min(this->backoff_ * 2, BACKOFF_MAX_MS);
+}
+
+void OutgoingConnectionManager::on_client_removed(APIConnection *conn, bool was_authenticated) {
+  if (conn != this->dialed_conn_) {
+    return;
+  }
+  this->dialed_conn_ = nullptr;
+  if (was_authenticated) {
+    // A working peer (e.g. a host: target that never sends the flag)
+    // disconnected normally; state is IDLE, so loop() applies the delay
+    this->backoff_ = BACKOFF_MIN_MS;
+  } else {
+    this->schedule_retry_(App.get_loop_component_start_time());
+  }
+}
+
+void OutgoingConnectionManager::on_target_client(APIConnection *conn) {
+  // The target is connected; stop any dial in flight and reset the backoff.
+  // A dialed connection stays tracked unless it is this one: an inbound
+  // target must not orphan a still-open dial.
+  this->dial_socket_.reset();
+  if (conn == this->dialed_conn_) {
+    this->dialed_conn_ = nullptr;
+  }
+  this->state_ = DialState::DIAL_STATE_IDLE;
+  this->backoff_ = BACKOFF_MIN_MS;
+#ifndef API_OUTGOING_CONNECTION_HOST
+  SavedOutgoingTarget target{};
+  if (!peer_to_target(conn, target)) {
+    ESP_LOGW(TAG, "Not remembering this target; its address cannot be dialed");
+    return;
+  }
+  if (this->host_persisted_ && memcmp(&target, &this->saved_, sizeof(target)) == 0) {
+    return;  // unchanged and already on flash; avoid flash wear
+  }
+  // Use the fresh address this boot even if the flash write fails; a failed
+  // write is retried on the next flagged hello via host_persisted_
+  this->saved_ = target;
+  if (!this->persist_target_()) {
+    ESP_LOGW(TAG, "Failed to save target");
+    return;
+  }
+  char host[socket::SOCKADDR_STR_LEN];
+  this->format_target_(host);
+  ESP_LOGD(TAG, "Remembered %s as the dial target", host);
+#endif
+}
+
+void OutgoingConnectionManager::dump_config() const {
+  // The boot delay differs from delay: on deep sleep builds, so print the
+  // value that actually applies
+  ESP_LOGCONFIG(TAG,
+                "  Outgoing connection port: %u\n"
+                "  Outgoing connection boot delay: %" PRIu32 "ms",
+                API_OUTGOING_CONNECTION_PORT, BOOT_WAIT_MS);
+  // Both forms keep their text out of RAM on ESP8266: in the format string,
+  // or through LOG_STR_LITERAL
+#ifdef API_OUTGOING_CONNECTION_HOST
+  ESP_LOGCONFIG(TAG, "  Outgoing connection host: " API_OUTGOING_CONNECTION_HOST);
+#else
+  char buf[socket::SOCKADDR_STR_LEN];
+  this->format_target_(buf);
+  ESP_LOGCONFIG(TAG, "  Outgoing connection host: %s", buf[0] == '\0' ? LOG_STR_LITERAL("none remembered yet") : buf);
+#endif
+}
+
+}  // namespace esphome::api
+#endif  // USE_API && USE_API_OUTGOING_CONNECTION
@@ -0,0 +1,120 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+#if defined(USE_API) && defined(USE_API_OUTGOING_CONNECTION)
+
+#ifndef USE_API_NOISE
+#error "api outgoing_connection needs noise encryption so the peer is verified by key"
+#endif
+
+#include "esphome/components/socket/socket.h"
+#include "esphome/core/preferences.h"
+
+#include <memory>
+
+namespace esphome::api {
+
+class APIServer;
+class APIConnection;
+
+// Room for an IPv6 address in every build, so a remembered IPv4 target is
+// still dialed after enable_ipv6 is turned on. A size that followed the build
+// would also shift every preference registered after this one on ESP8266,
+// where slots are positional. An IPv6 target on a build without IPv6 is
+// dropped by target_sockaddr_() and relearned.
+// Bytes in an IPv6 address
+static constexpr size_t TARGET_ADDR_LEN = 16;
+
+struct SavedOutgoingTarget {
+  // 0 when none is remembered, else AF_INET or AF_INET6
+  uint8_t family;
+  // Network order, IPv4 in the first four bytes and the rest zero
+  uint8_t addr[TARGET_ADDR_LEN];
+  // Interface a link-local IPv6 target is reachable on, 0 when it needs none.
+  // Free in flash: the record still rounds up to the same five words.
+  uint8_t scope_id;
+} PACKED;  // NOLINT
+
+/// Dials out when no dial-back target client is connected. Only the TCP
+/// direction flips: the device stays the Noise responder, so both sides
+/// still verify by key. Targets the YAML host or the last remembered client.
+class OutgoingConnectionManager {
+ public:
+  void setup();
+  void loop(APIServer *server);
+  /// A key-verified client declared itself a dial-back target; last one wins
+  void on_target_client(APIConnection *conn);
+  /// Clears the dialed-connection gate; dying unauthenticated escalates the backoff
+  void on_client_removed(APIConnection *conn, bool was_authenticated);
+  void on_shutdown() { this->dial_socket_.reset(); }
+  void dump_config() const;
+
+ protected:
+  enum class DialState : uint8_t {
+    DIAL_STATE_IDLE,
+    DIAL_STATE_WAITING,
+    DIAL_STATE_CONNECTING,
+  };
+
+  static constexpr uint32_t BACKOFF_MIN_MS = 5000;
+  static constexpr uint32_t BACKOFF_MAX_MS = 300000;
+  static constexpr uint32_t CONNECT_TIMEOUT_MS = 10000;
+  static constexpr uint32_t CONNECT_POLL_INTERVAL_MS = 250;
+  static constexpr uint32_t NETWORK_RETRY_MS = 500;
+  static constexpr uint32_t PRECONDITION_RETRY_MS = 5000;
+  // A deep sleep wake window is too short to spend on the delay, so those
+  // builds dial out as soon as the target is gone
+#ifdef USE_DEEP_SLEEP
+  static constexpr uint32_t BOOT_WAIT_MS = 0;
+  static constexpr uint32_t IDLE_WAIT_MS = BACKOFF_MIN_MS;
+#else
+  static constexpr uint32_t BOOT_WAIT_MS = API_OUTGOING_CONNECTION_DELAY;
+  static constexpr uint32_t IDLE_WAIT_MS = API_OUTGOING_CONNECTION_DELAY;
+#endif
+
+  void try_dial_(APIServer *server, uint32_t now);
+  void poll_connect_(APIServer *server, uint32_t now);
+  // Hand the connected socket to the server and gate on the new connection
+  void handoff_(APIServer *server, uint32_t now);
+  // Close any half-open dial and wait a jittered backoff before retrying
+  void schedule_retry_(uint32_t now);
+  // Wait without escalating the backoff (used for unmet preconditions)
+  void schedule_wait_(uint32_t now, uint32_t wait);
+  /// Fill addr with the target and return its length, or 0 when there is none
+  socklen_t target_sockaddr_(struct sockaddr_storage *addr) const;
+#ifndef API_OUTGOING_CONNECTION_HOST
+  // Write saved_ to flash, tracking success in host_persisted_
+  bool persist_target_() {
+    this->host_persisted_ = this->target_pref_.save(&this->saved_) && global_preferences->sync();
+    return this->host_persisted_;
+  }
+  /// Format the remembered target for a log line; empty when there is none
+  void format_target_(std::span<char, socket::SOCKADDR_STR_LEN> buf) const;
+#endif
+
+  // Pointers first (4 bytes each on 32-bit)
+  std::unique_ptr<socket::Socket> dial_socket_;
+  // Compared only, never dereferenced
+  APIConnection *dialed_conn_{nullptr};
+#ifndef API_OUTGOING_CONNECTION_HOST
+  ESPPreferenceObject target_pref_;
+#endif
+
+  // 4-byte types
+  uint32_t backoff_{BACKOFF_MIN_MS};
+  uint32_t wait_{BOOT_WAIT_MS};
+  uint32_t state_ts_{0};
+  uint32_t last_poll_{0};
+
+  // Byte-aligned types last
+#ifndef API_OUTGOING_CONNECTION_HOST
+  SavedOutgoingTarget saved_{};
+  // False while saved_ holds a value the flash write failed for; retried on
+  // the next flagged hello
+  bool host_persisted_{false};
+#endif
+  DialState state_{DialState::DIAL_STATE_WAITING};
+};
+
+}  // namespace esphome::api
+#endif  // USE_API && USE_API_OUTGOING_CONNECTION
@@ -114,15 +114,26 @@ template<typename T> static void dump_field(DumpBuffer &out, const char *field_n
  out.append("\n");
 }

+// Bytes shown by a bytes field dump: 160 bytes is 480 chars with separators, to fit a typical log buffer
+static constexpr size_t DUMP_BYTES_MAX = 160;
+
 // Helper for bytes fields - uses stack buffer to avoid heap allocation
-// Buffer sized for 160 bytes of data (480 chars with separators) to fit typical log buffer
 // field_name is a PROGMEM pointer (flash on ESP8266, regular pointer on other platforms)
 static void dump_bytes_field(DumpBuffer &out, const char *field_name, const uint8_t *data, size_t len, int indent = 2) {
-  char hex_buf[format_hex_pretty_size(160)];
+  char hex_buf[format_hex_pretty_size(DUMP_BYTES_MAX)];
  append_field_prefix(out, field_name, indent);
  format_hex_pretty_to(hex_buf, data, len);
  out.append(hex_buf).append("\n");
 }
+
+// Helper for bytes fields in flash: copies the shown bytes out with progmem_memcpy first
+static void dump_progmem_bytes_field(DumpBuffer &out, const char *field_name, const uint8_t *data, size_t len,
+                                     int indent = 2) {
+  uint8_t data_buf[DUMP_BYTES_MAX];
+  len = std::min(len, sizeof(data_buf));
+  progmem_memcpy(data_buf, data, len);
+  dump_bytes_field(out, field_name, data_buf, len, indent);
+}
 #pragma GCC diagnostic pop

 template<> const char *proto_enum_to_string<enums::DisconnectReason>(enums::DisconnectReason value) {
@@ -143,6 +154,8 @@ template<> const char *proto_enum_to_string<enums::SerialProxyPortType>(enums::S
      return ESPHOME_PSTR("SERIAL_PROXY_PORT_TYPE_RS232");
    case enums::SERIAL_PROXY_PORT_TYPE_RS485:
      return ESPHOME_PSTR("SERIAL_PROXY_PORT_TYPE_RS485");
+    case enums::SERIAL_PROXY_PORT_TYPE_USB_SERIAL:
+      return ESPHOME_PSTR("SERIAL_PROXY_PORT_TYPE_USB_SERIAL");
    default:
      return ESPHOME_PSTR("UNKNOWN");
  }
@@ -890,6 +903,49 @@ template<> const char *proto_enum_to_string<enums::SerialProxyMode>(enums::Seria
      return ESPHOME_PSTR("UNKNOWN");
  }
 }
+template<> const char *proto_enum_to_string<enums::SerialProxyIdentitySource>(enums::SerialProxyIdentitySource value) {
+  switch (value) {
+    case enums::SERIAL_PROXY_IDENTITY_SOURCE_NONE:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_SOURCE_NONE");
+    case enums::SERIAL_PROXY_IDENTITY_SOURCE_CONFIGURED:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_SOURCE_CONFIGURED");
+    case enums::SERIAL_PROXY_IDENTITY_SOURCE_USB:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_SOURCE_USB");
+    default:
+      return ESPHOME_PSTR("UNKNOWN");
+  }
+}
+#endif
+template<> const char *proto_enum_to_string<enums::SerialProxyIdentityFlag>(enums::SerialProxyIdentityFlag value) {
+  switch (value) {
+    case enums::SERIAL_PROXY_IDENTITY_FLAG_NONE:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_FLAG_NONE");
+    case enums::SERIAL_PROXY_IDENTITY_FLAG_CONNECTED:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_FLAG_CONNECTED");
+    case enums::SERIAL_PROXY_IDENTITY_FLAG_ERROR:
+      return ESPHOME_PSTR("SERIAL_PROXY_IDENTITY_FLAG_ERROR");
+    default:
+      return ESPHOME_PSTR("UNKNOWN");
+  }
+}
+#ifdef USE_SENDSPIN
+template<>
+const char *proto_enum_to_string<enums::SendspinPairingTokenStatus>(enums::SendspinPairingTokenStatus value) {
+  switch (value) {
+    case enums::SENDSPIN_PAIRING_TOKEN_STATUS_NOT_READY:
+      return ESPHOME_PSTR("SENDSPIN_PAIRING_TOKEN_STATUS_NOT_READY");
+    case enums::SENDSPIN_PAIRING_TOKEN_STATUS_OK:
+      return ESPHOME_PSTR("SENDSPIN_PAIRING_TOKEN_STATUS_OK");
+    case enums::SENDSPIN_PAIRING_TOKEN_STATUS_ENCRYPTION_REQUIRED:
+      return ESPHOME_PSTR("SENDSPIN_PAIRING_TOKEN_STATUS_ENCRYPTION_REQUIRED");
+    case enums::SENDSPIN_PAIRING_TOKEN_STATUS_DISABLED:
+      return ESPHOME_PSTR("SENDSPIN_PAIRING_TOKEN_STATUS_DISABLED");
+    case enums::SENDSPIN_PAIRING_TOKEN_STATUS_FAILED:
+      return ESPHOME_PSTR("SENDSPIN_PAIRING_TOKEN_STATUS_FAILED");
+    default:
+      return ESPHOME_PSTR("UNKNOWN");
+  }
+}
 #endif

 const char *HelloRequest::dump_to(DumpBuffer &out) const {
@@ -897,6 +953,9 @@ const char *HelloRequest::dump_to(DumpBuffer &out) const {
  dump_field(out, ESPHOME_PSTR("client_info"), this->client_info);
  dump_field(out, ESPHOME_PSTR("api_version_major"), this->api_version_major);
  dump_field(out, ESPHOME_PSTR("api_version_minor"), this->api_version_minor);
+#ifdef USE_API_OUTGOING_CONNECTION
+  dump_field(out, ESPHOME_PSTR("outgoing_connection_target"), this->outgoing_connection_target);
+#endif
  return out.c_str();
 }
 const char *HelloResponse::dump_to(DumpBuffer &out) const {
@@ -1020,6 +1079,9 @@ const char *DeviceInfoResponse::dump_to(DumpBuffer &out) const {
 #endif
 #ifdef USE_API_NOISE
  dump_field(out, ESPHOME_PSTR("api_encryption_provisionable"), this->api_encryption_provisionable);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  dump_field(out, ESPHOME_PSTR("api_outgoing_connection_supported"), this->api_outgoing_connection_supported);
 #endif
  return out.c_str();
 }
@@ -1046,6 +1108,20 @@ const char *ZWaveProxyCapabilities::dump_to(DumpBuffer &out) const {
  return out.c_str();
 }
 #endif
+#ifdef USE_API_WIZARD
+const char *WizardCapabilities::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("WizardCapabilities"));
+  dump_field(out, ESPHOME_PSTR("configured"), this->configured);
+  return out.c_str();
+}
+#endif
+#ifdef USE_SENDSPIN
+const char *SendspinCapabilities::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("SendspinCapabilities"));
+  dump_field(out, ESPHOME_PSTR("feature_flags"), this->feature_flags);
+  return out.c_str();
+}
+#endif
 const char *DeviceCapabilitiesResponse::dump_to(DumpBuffer &out) const {
  MessageDumpHelper helper(out, ESPHOME_PSTR("DeviceCapabilitiesResponse"));
 #ifdef USE_BLUETOOTH_PROXY
@@ -1069,9 +1145,34 @@ const char *DeviceCapabilitiesResponse::dump_to(DumpBuffer &out) const {
    it.dump_to(out);
    out.append("\n");
  }
+#endif
+#ifdef USE_API_WIZARD
+  out.append(2, ' ').append_p(ESPHOME_PSTR("wizard")).append(": ");
+  this->wizard.dump_to(out);
+  out.append("\n");
+#endif
+#ifdef USE_SENDSPIN
+  out.append(2, ' ').append_p(ESPHOME_PSTR("sendspin")).append(": ");
+  this->sendspin.dump_to(out);
+  out.append("\n");
 #endif
  return out.c_str();
 }
+#ifdef USE_API_WIZARD
+const char *DeviceWizardResponse::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("DeviceWizardResponse"));
+  dump_progmem_bytes_field(out, ESPHOME_PSTR("data"), this->data, this->data_len);
+  return out.c_str();
+}
+#endif
+#ifdef USE_API_WIZARD_INPUTS
+const char *WizardInputSetRequest::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("WizardInputSetRequest"));
+  dump_field(out, ESPHOME_PSTR("key"), this->key);
+  dump_field(out, ESPHOME_PSTR("entity_id"), this->entity_id);
+  return out.c_str();
+}
+#endif
 const char *ListEntitiesDoneResponse::dump_to(DumpBuffer &out) const {
  out.append_p(ESPHOME_PSTR("ListEntitiesDoneResponse {}"));
  return out.c_str();
@@ -2714,7 +2815,7 @@ const char *ListEntitiesInfraredResponse::dump_to(DumpBuffer &out) const {
  return out.c_str();
 }
 #endif
-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
 const char *InfraredRFTransmitRawTimingsRequest::dump_to(DumpBuffer &out) const {
  MessageDumpHelper helper(out, ESPHOME_PSTR("InfraredRFTransmitRawTimingsRequest"));
 #ifdef USE_DEVICES
@@ -2743,6 +2844,15 @@ const char *InfraredRFReceiveEvent::dump_to(DumpBuffer &out) const {
  }
  return out.c_str();
 }
+const char *InfraredRFTransmitCompleteResponse::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("InfraredRFTransmitCompleteResponse"));
+#ifdef USE_DEVICES
+  dump_field(out, ESPHOME_PSTR("device_id"), this->device_id);
+#endif
+  dump_field(out, ESPHOME_PSTR("key"), this->key);
+  dump_field(out, ESPHOME_PSTR("success"), this->success);
+  return out.c_str();
+}
 #endif
 #ifdef USE_RADIO_FREQUENCY
 const char *ListEntitiesRadioFrequencyResponse::dump_to(DumpBuffer &out) const {
@@ -2826,6 +2936,27 @@ const char *SerialProxySetModeRequest::dump_to(DumpBuffer &out) const {
  dump_field(out, ESPHOME_PSTR("mode"), static_cast<enums::SerialProxyMode>(this->mode));
  return out.c_str();
 }
+const char *UsbDeviceDescriptor::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("UsbDeviceDescriptor"));
+  dump_field(out, ESPHOME_PSTR("vendor_id"), this->vendor_id);
+  dump_field(out, ESPHOME_PSTR("product_id"), this->product_id);
+  dump_field(out, ESPHOME_PSTR("bcd_device"), this->bcd_device);
+  dump_field(out, ESPHOME_PSTR("interface_number"), this->interface_number);
+  return out.c_str();
+}
+const char *SerialProxyIdentity::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("SerialProxyIdentity"));
+  dump_field(out, ESPHOME_PSTR("instance"), this->instance);
+  dump_field(out, ESPHOME_PSTR("source"), static_cast<enums::SerialProxyIdentitySource>(this->source));
+  dump_field(out, ESPHOME_PSTR("flags"), this->flags);
+  dump_field(out, ESPHOME_PSTR("manufacturer"), this->manufacturer);
+  dump_field(out, ESPHOME_PSTR("product"), this->product);
+  dump_field(out, ESPHOME_PSTR("serial_number"), this->serial_number);
+  out.append(2, ' ').append_p(ESPHOME_PSTR("usb")).append(": ");
+  this->usb.dump_to(out);
+  out.append("\n");
+  return out.c_str();
+}
 #endif
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
 const char *BluetoothSetConnectionParamsRequest::dump_to(DumpBuffer &out) const {
@@ -2844,6 +2975,14 @@ const char *BluetoothSetConnectionParamsResponse::dump_to(DumpBuffer &out) const
  return out.c_str();
 }
 #endif
+#ifdef USE_SENDSPIN
+const char *SendspinPairingTokenResponse::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("SendspinPairingTokenResponse"));
+  dump_field(out, ESPHOME_PSTR("status"), static_cast<enums::SendspinPairingTokenStatus>(this->status));
+  dump_field(out, ESPHOME_PSTR("token"), this->token);
+  return out.c_str();
+}
+#endif

 }  // namespace esphome::api

@@ -28,6 +28,7 @@

 // Standard library includes that might be needed
 #include <set>
+#include <span>
 #include <vector>
 #include <string>

@@ -628,7 +628,7 @@ void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const ui
      break;
    }
 #endif
-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
    case InfraredRFTransmitRawTimingsRequest::MESSAGE_TYPE: {
      InfraredRFTransmitRawTimingsRequest msg;
      msg.decode(msg_data, msg_size);
@@ -722,6 +722,44 @@ void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const ui
      this->on_serial_proxy_set_mode_request(msg);
      break;
    }
+#endif
+#ifdef USE_SERIAL_PROXY
+    case 154 /* SubscribeSerialProxyIdentityRequest is empty */: {
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      this->log_receive_message_(LOG_STR("on_subscribe_serial_proxy_identity_request"));
+#endif
+      this->on_subscribe_serial_proxy_identity_request();
+      break;
+    }
+#endif
+#ifdef USE_API_WIZARD
+    case 156 /* DeviceWizardRequest is empty */: {
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      this->log_receive_message_(LOG_STR("on_device_wizard_request"));
+#endif
+      this->on_device_wizard_request();
+      break;
+    }
+#endif
+#ifdef USE_API_WIZARD_INPUTS
+    case WizardInputSetRequest::MESSAGE_TYPE: {
+      WizardInputSetRequest msg;
+      msg.decode(msg_data, msg_size);
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      this->log_receive_message_(LOG_STR("on_wizard_input_set_request"), msg);
+#endif
+      this->on_wizard_input_set_request(msg);
+      break;
+    }
+#endif
+#ifdef USE_SENDSPIN
+    case 159 /* SendspinPairingTokenRequest is empty */: {
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      this->log_receive_message_(LOG_STR("on_sendspin_pairing_token_request"));
+#endif
+      this->on_sendspin_pairing_token_request();
+      break;
+    }
 #endif
    default:
      break;
@@ -29,6 +29,13 @@ class APIServerConnectionBase {

  void on_device_capabilities_request(){};

+#ifdef USE_API_WIZARD
+  void on_device_wizard_request(){};
+#endif
+
+#ifdef USE_API_WIZARD_INPUTS
+  void on_wizard_input_set_request(const WizardInputSetRequest &value){};
+#endif
  void on_list_entities_request(){};

  void on_subscribe_states_request(){};
@@ -213,7 +220,7 @@ class APIServerConnectionBase {
  void on_z_wave_proxy_request(const ZWaveProxyRequest &value){};
 #endif

-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_IR_RF
  void on_infrared_rf_transmit_raw_timings_request(const InfraredRFTransmitRawTimingsRequest &value){};
 #endif

@@ -238,9 +245,17 @@ class APIServerConnectionBase {
 #ifdef USE_SERIAL_PROXY
  void on_serial_proxy_set_mode_request(const SerialProxySetModeRequest &value){};
 #endif
+#ifdef USE_SERIAL_PROXY
+  void on_subscribe_serial_proxy_identity_request(){};
+#endif
+
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
  void on_bluetooth_set_connection_params_request(const BluetoothSetConnectionParamsRequest &value){};
 #endif
+
+#ifdef USE_SENDSPIN
+  void on_sendspin_pairing_token_request(){};
+#endif
 };

 }  // namespace esphome::api
@@ -56,7 +56,12 @@ APIServer::APIServer() { global_api_server = this; }
 void APIServer::socket_failed_(const LogString *msg) {
  ESP_LOGW(TAG, "Socket %s: errno %d", LOG_STR_ARG(msg), errno);
  this->destroy_socket_();
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Dial-out needs no listener; degrade instead of stopping the component
+  this->status_set_error(LOG_STR("listen socket failed"));
+#else
  this->mark_failed();
+#endif
 }

 void APIServer::setup() {
@@ -72,43 +77,6 @@ void APIServer::setup() {
 #endif
 #endif

-  this->socket_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0).release();  // monitored for incoming connections
-  if (this->socket_ == nullptr) {
-    this->socket_failed_(LOG_STR("creation"));
-    return;
-  }
-  int enable = 1;
-  int err = this->socket_->setsockopt(SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
-  if (err != 0) {
-    ESP_LOGW(TAG, "Socket reuseaddr: errno %d", errno);
-    // we can still continue
-  }
-  err = this->socket_->setblocking(false);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("nonblocking"));
-    return;
-  }
-
-  struct sockaddr_storage server;
-
-  socklen_t sl = socket::set_sockaddr_any((struct sockaddr *) &server, sizeof(server), this->port_);
-  if (sl == 0) {
-    this->socket_failed_(LOG_STR("set sockaddr"));
-    return;
-  }
-
-  err = this->socket_->bind((struct sockaddr *) &server, sl);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("bind"));
-    return;
-  }
-
-  err = this->socket_->listen(this->listen_backlog_);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("listen"));
-    return;
-  }
-
 #ifdef USE_LOGGER
  if (logger::global_logger != nullptr) {
    logger::global_logger->add_log_callback(
@@ -154,6 +122,47 @@ void APIServer::setup() {
  if (this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
    this->status_set_warning(LOG_STR("waiting for client connection"));
  }
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.setup();
+#endif
+
+  // Listener last: on failure socket_failed_() returns early, and an
+  // outgoing_connection build keeps dialing out without one
+  this->socket_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0).release();  // monitored for incoming connections
+  if (this->socket_ == nullptr) {
+    this->socket_failed_(LOG_STR("creation"));
+    return;
+  }
+  int enable = 1;
+  int err = this->socket_->setsockopt(SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
+  if (err != 0) {
+    ESP_LOGW(TAG, "Socket reuseaddr: errno %d", errno);
+    // we can still continue
+  }
+  err = this->socket_->setblocking(false);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("nonblocking"));
+    return;
+  }
+
+  struct sockaddr_storage server;
+
+  socklen_t sl = socket::set_sockaddr_any((struct sockaddr *) &server, sizeof(server), this->port_);
+  if (sl == 0) {
+    this->socket_failed_(LOG_STR("set sockaddr"));
+    return;
+  }
+
+  err = this->socket_->bind((struct sockaddr *) &server, sl);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("bind"));
+    return;
+  }
+
+  err = this->socket_->listen(this->listen_backlog_);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("listen"));
+  }
 }

 void APIServer::loop() {
@@ -162,6 +171,19 @@ 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
+
+#ifdef USE_API_OUTGOING_CONNECTION
+  if (!this->shutting_down_) {
+    this->outgoing_conn_.loop(this);
+  }
+#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 +200,7 @@ 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 +228,19 @@ 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];

@@ -222,6 +256,15 @@ void APIServer::remove_client_(uint8_t client_index) {
  std::string client_peername(client->get_peername_to(peername_buf));
 #endif

+  // Read before the swap-and-reset below destroys the connection
+  const bool was_authenticated = client->is_authenticated();
+#ifdef USE_API_OUTGOING_CONNECTION
+  if (client->flags_.outgoing_connection_target) {
+    this->outgoing_target_count_--;
+  }
+  this->outgoing_conn_.on_client_removed(client.get(), was_authenticated);
+#endif
+
  // Close socket now (was deferred from on_fatal_error to allow getpeername)
  client->helper_->close();

@@ -240,9 +283,15 @@ void APIServer::remove_client_(uint8_t client_index) {

  // Last client disconnected - set warning and start tracking for reboot timeout
  // (suppressed while provisioning is pending - see loop()).
+  // Refresh on every authenticated removal, not just the last one, so an
+  // unauthenticated straggler removed later (e.g. a port scan, or a dial to
+  // a host that accepts TCP but never speaks the API) cannot discard a
+  // healthy session's timestamp and trigger a spurious reboot
+  if (was_authenticated) {
+    this->last_connected_ = App.get_loop_component_start_time();
+  }
  if (this->api_connection_count_ == 0 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
    this->status_set_warning(LOG_STR("waiting for client connection"));
-    this->last_connected_ = App.get_loop_component_start_time();
  }

 #ifdef USE_API_CLIENT_DISCONNECTED_TRIGGER
@@ -264,7 +313,7 @@ void __attribute__((flatten)) APIServer::accept_new_connections_() {
    sock->getpeername_to(peername);

    // Check if we're at the connection limit
-    if (this->api_connection_count_ >= MAX_API_CONNECTIONS) {
+    if (this->at_client_limit_()) {
      ESP_LOGW(TAG, "Max connections (%d), rejecting %s", MAX_API_CONNECTIONS, peername);
      // Immediately close - socket destructor will handle cleanup
      sock.reset();
@@ -273,18 +322,47 @@ void __attribute__((flatten)) APIServer::accept_new_connections_() {

    ESP_LOGD(TAG, "Accept %s", peername);

-    auto *conn = new APIConnection(std::move(sock), this);
-    this->clients_[this->api_connection_count_++].reset(conn);
-    conn->start();
-
-    // First client connected - clear warning and update timestamp
-    if (this->api_connection_count_ == 1 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
-      this->status_clear_warning();
-      this->last_connected_ = App.get_loop_component_start_time();
-    }
+    this->add_client_(std::move(sock));
  }
 }

+APIConnection *APIServer::add_client_(std::unique_ptr<socket::Socket> sock) {
+  auto *conn = new APIConnection(std::move(sock), this);  // NOLINT(cppcoreguidelines-owning-memory)
+  this->clients_[this->api_connection_count_++].reset(conn);
+  conn->start();
+
+  // First client connected - clear warning. The reboot watchdog timestamp is
+  // refreshed when an authenticated client is removed (see remove_client_),
+  // never on bare TCP connects.
+  if (this->api_connection_count_ == 1 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
+    this->status_clear_warning();
+  }
+  return conn;
+}
+
+#ifdef USE_API_OUTGOING_CONNECTION
+APIConnection *APIServer::add_outgoing_client_(std::unique_ptr<socket::Socket> sock) {
+  // Re-check at the handoff: inbound clients may have taken the last slot and
+  // the PSK may have been cleared since the dial started (mark_outgoing()
+  // needs the noise helper)
+  const bool at_limit = this->at_client_limit_();
+  if (at_limit || !this->noise_ctx_.has_psk()) {
+    ESP_LOGW(TAG, "Dropping outgoing connection (%s)",
+             at_limit ? LOG_STR_LITERAL("max connections") : LOG_STR_LITERAL("no key"));
+    return nullptr;
+  }
+  auto *conn = this->add_client_(std::move(sock));
+  // After start(): sends our server hello first so the peer can pick the key
+  conn->mark_outgoing();
+  return conn;
+}
+
+void APIServer::on_outgoing_target_client(APIConnection *conn) {
+  this->outgoing_target_count_++;
+  this->outgoing_conn_.on_target_client(conn);
+}
+#endif
+
 void APIServer::dump_config() {
  char addr_buf[network::USE_ADDRESS_BUFFER_SIZE];
  ESP_LOGCONFIG(TAG,
@@ -301,6 +379,9 @@ void APIServer::dump_config() {
 #else
  ESP_LOGCONFIG(TAG, "  Noise encryption: NO");
 #endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.dump_config();
+#endif
 }

 void APIServer::handle_disconnect(APIConnection *conn) {}
@@ -423,7 +504,16 @@ void APIServer::on_zwave_proxy_request(const ZWaveProxyRequest &msg) {
 }
 #endif

-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_SERIAL_PROXY_USB_IDENTITY
+void APIServer::send_serial_proxy_identity(const SerialProxyIdentity &msg) {
+  for (auto &c : this->active_clients()) {
+    if (c->flags_.serial_proxy_identity_subscription)
+      c->send_serial_proxy_identity(msg);
+  }
+}
+#endif
+
+#ifdef USE_IR_RF
 void APIServer::send_infrared_rf_receive_event([[maybe_unused]] uint32_t device_id, uint32_t key,
                                               const std::vector<int32_t> *timings) {
  InfraredRFReceiveEvent resp{};
@@ -436,6 +526,7 @@ void APIServer::send_infrared_rf_receive_event([[maybe_unused]] uint32_t device_
  for (auto &c : this->active_clients())
    c->send_infrared_rf_receive_event(resp);
 }
+
 #endif

 #ifdef USE_ALARM_CONTROL_PANEL
@@ -597,6 +688,8 @@ bool APIServer::update_noise_psk_(const SavedNoisePsk &new_psk, const LogString
        if (!c->send_message(req)) {
          API_LOG_MSG_DROPPED(TAG, "Disconnect request");
        }
+        // Force it: a session from before the key was active must not survive
+        c->flags_.next_close = true;
      }
    });
  }
@@ -698,6 +791,9 @@ void APIServer::on_shutdown() {

  // Close the listening socket to prevent new connections
  this->destroy_socket_();
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.on_shutdown();
+#endif

  // Change batch delay to 5ms for quick flushing during shutdown
  this->batch_delay_ = 5;
@@ -5,12 +5,13 @@
 #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
 #include "api_pb2.h"
 #include "api_pb2_service.h"
+#include "api_outgoing_connection.h"
 #include "esphome/components/socket/socket.h"
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
@@ -90,6 +91,10 @@ class APIServer final : public Component
  void set_noise_psk(const uint8_t *psk) { this->noise_ctx_.set_psk(psk); }
  noise::NoiseContext &get_noise_ctx() { return this->noise_ctx_; }
 #endif  // USE_API_NOISE
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Called by APIConnection when a client declares itself a dial-back target in its hello
+  void on_outgoing_target_client(APIConnection *conn);
+#endif

  void handle_disconnect(APIConnection *conn);
 #ifdef USE_BINARY_SENSOR
@@ -198,7 +203,11 @@ class APIServer final : public Component
 #ifdef USE_ZWAVE_PROXY
  void on_zwave_proxy_request(const ZWaveProxyRequest &msg);
 #endif
-#if defined(USE_IR_RF) || defined(USE_RADIO_FREQUENCY)
+#ifdef USE_SERIAL_PROXY_USB_IDENTITY
+  /// Tell every subscribed client that a serial proxy port's identity changed
+  void send_serial_proxy_identity(const SerialProxyIdentity &msg);
+#endif
+#ifdef USE_IR_RF
  void send_infrared_rf_receive_event(uint32_t device_id, uint32_t key, const std::vector<int32_t> *timings);
 #endif

@@ -267,6 +276,16 @@ class APIServer final : public Component
 protected:
  // Accept incoming socket connections. Only called when socket has pending connections.
  void __attribute__((noinline)) accept_new_connections_();
+  /// Takes the socket into a new connection and starts it; callers must have
+  /// checked at_client_limit_() first
+  APIConnection *add_client_(std::unique_ptr<socket::Socket> sock);
+  bool at_client_limit_() const { return this->api_connection_count_ >= MAX_API_CONNECTIONS; }
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Returns the new connection, or nullptr (socket dropped) when at the limit
+  APIConnection *add_outgoing_client_(std::unique_ptr<socket::Socket> sock);
+  bool has_outgoing_target_client_() const { return this->outgoing_target_count_ != 0; }
+  friend class OutgoingConnectionManager;
+#endif
  // Remove a disconnected client by index. Swaps with the last populated slot and resets it.
  void __attribute__((noinline)) remove_client_(uint8_t client_index);

@@ -307,6 +326,8 @@ class APIServer final : public Component
    delete this->socket_;
    this->socket_ = nullptr;
  }
+  /// Log the failure, drop the listen socket, and mark the component failed
+  /// unless this build can still dial out
  void socket_failed_(const LogString *msg);
  // Pointers and pointer-like types first (4 bytes each)
  socket::ListenSocket *socket_{nullptr};
@@ -357,16 +378,21 @@ class APIServer final : public Component
  // Group smaller types together
  uint16_t port_{6053};        // Keep in sync with DEFAULT_PORT in __init__.py
  uint16_t batch_delay_{100};  // Keep in sync with DEFAULT_BATCH_DELAY in __init__.py
-  // Connection limits - these defaults will be overridden by config values
-  // from cv.SplitDefault in __init__.py which sets platform-specific defaults.
-  uint8_t listen_backlog_{4};
+  uint8_t listen_backlog_{4};  // Keep in sync with DEFAULT_LISTEN_BACKLOG in __init__.py
  bool shutting_down_ = false;
  uint8_t api_connection_count_{0};
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Connected clients whose hello declared them a dial-back target
+  uint8_t outgoing_target_count_{0};
+#endif
 #if defined(USE_PROVISIONING) && defined(USE_API_NOISE)
  // Index assigned by the provisioning manager for reporting this transport's state.
  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
@@ -374,6 +400,9 @@ class APIServer final : public Component
 #endif
  ESPPreferenceObject noise_pref_;
 #endif  // USE_API_NOISE
+#ifdef USE_API_OUTGOING_CONNECTION
+  OutgoingConnectionManager outgoing_conn_;
+#endif
 };

 extern APIServer *global_api_server;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
@@ -0,0 +1,128 @@
+#include "api_wizard.h"
+
+#ifdef USE_API_WIZARD
+
+#include <cstring>
+
+#include "api_connection.h"
+#include "api_pb2.h"
+#include "api_server.h"
+#include "esphome/core/log.h"
+
+namespace esphome::api {
+
+static const char *const TAG = "api.wizard";
+
+#ifdef USE_API_WIZARD_INPUTS
+#ifdef USE_API_WIZARD_MULTIPLE_INPUTS
+// Walks the comma separated entity ids in value, without the spaces around each. Returns the length they take joined
+// by ',', or 0 when one is empty or has no '.'. Writes the joined list to out unless it is nullptr.
+static size_t wizard_join_entity_ids(const char *value, size_t length, char *out) {
+  size_t joined = 0;
+  const char *end = value + length;
+  while (true) {
+    const char *comma = static_cast<const char *>(memchr(value, ',', end - value));
+    const char *id_end = comma != nullptr ? comma : end;
+    while (value < id_end && *value == ' ')
+      value++;
+    while (id_end > value && id_end[-1] == ' ')
+      id_end--;
+    size_t id_length = id_end - value;
+    if (id_length == 0 || memchr(value, '.', id_length) == nullptr)
+      return 0;
+    if (joined != 0) {
+      if (out != nullptr)
+        out[joined] = ',';
+      joined++;
+    }
+    if (out != nullptr)
+      memcpy(out + joined, value, id_length);
+    joined += id_length;
+    if (comma == nullptr)
+      return joined;
+    value = comma + 1;
+  }
+}
+#endif  // USE_API_WIZARD_MULTIPLE_INPUTS
+
+static bool wizard_entity_id_valid(const char *entity_id, size_t length) {
+  return length > 0 && length < WIZARD_ENTITY_ID_BUFFER_SIZE && memchr(entity_id, '.', length) != nullptr;
+}
+
+const char *wizard_set_input(const WizardInputSetRequest &msg) {
+  const char *value = msg.entity_id.c_str();
+  const size_t length = msg.entity_id.size();
+  for (size_t i = 0; i < API_WIZARD_INPUT_COUNT; i++) {
+    // The table is in flash, which ESP8266 can only read through progmem_memcpy
+    WizardInputEntry entry;
+    progmem_memcpy(&entry, &API_WIZARD_INPUTS[i], sizeof(entry));
+    if (entry.key != msg.key)
+      continue;
+#ifdef USE_API_WIZARD_MULTIPLE_INPUTS
+    if (entry.size != 0) {
+      // Two passes, validate and measure then write, so a rejected request leaves the buffer unchanged
+      const size_t joined = wizard_join_entity_ids(value, length, nullptr);
+      if (joined == 0 || joined >= entry.size)
+        break;
+      wizard_join_entity_ids(value, length, entry.entity_id);
+      entry.entity_id[joined] = '\0';
+      return entry.entity_id;
+    }
+#endif
+    if (!wizard_entity_id_valid(value, length))
+      break;
+    memcpy(entry.entity_id, value, length);
+    entry.entity_id[length] = '\0';
+    return entry.entity_id;
+  }
+  ESP_LOGW(TAG, "Ignoring an entity id for an unknown wizard input, or one that is not valid");
+  return nullptr;
+}
+#endif  // USE_API_WIZARD_INPUTS
+
+void APIConnection::on_device_wizard_request() {
+  DeviceWizardResponse resp;
+  resp.data = API_WIZARD_DATA;
+  resp.data_len = API_WIZARD_DATA_SIZE;
+  if (!this->send_message(resp)) {
+    this->on_fatal_error();
+  }
+}
+
+#ifdef USE_API_WIZARD_INPUTS
+void APIConnection::on_wizard_input_set_request(const WizardInputSetRequest &msg) {
+  const char *entity_id = wizard_set_input(msg);
+  if (entity_id == nullptr)
+    return;
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+  // Entities subscribed to the buffer before it held an entity id, so every client needs to learn of it now
+  for (auto &client : this->parent_->active_clients()) {
+    client->resend_state_subscriptions(entity_id);
+  }
+#endif
+}
+#endif
+
+#ifdef USE_API_WIZARD_LINKED_INPUTS
+void APIConnection::resend_state_subscriptions(const char *entity_id) {
+  if (!this->flags_.home_assistant_states)
+    return;
+  for (const auto &it : this->parent_->get_state_subs()) {
+    if (it.entity_id != entity_id)
+      continue;
+    SubscribeHomeAssistantStateResponse resp;
+    resp.entity_id = StringRef(it.entity_id);
+    resp.attribute = it.attribute != nullptr ? StringRef(it.attribute) : StringRef("");
+    resp.once = it.once;
+    if (!this->send_message(resp)) {
+      // Could not send now: send every subscription again from the loop
+      this->state_subs_at_ = 0;
+      return;
+    }
+  }
+}
+#endif
+
+}  // namespace esphome::api
+
+#endif  // USE_API_WIZARD
@@ -0,0 +1,89 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_API_WIZARD
+
+#include <cstddef>
+#include <cstdint>
+#ifdef USE_API_WIZARD_MULTIPLE_INPUTS
+#include <cstring>
+#endif
+
+#include "esphome/core/hal.h"
+#include "proto.h"
+#include "esphome/core/string_ref.h"
+
+namespace esphome::api {
+
+class WizardInputSetRequest;
+
+/// Size of the buffer holding the entity id of a wizard input. Home Assistant entity ids are at most 255 bytes.
+static constexpr size_t WIZARD_ENTITY_ID_BUFFER_SIZE = 256;
+
+/// The wizard as zstd compressed JSON (see DeviceWizardResponse), built by the generated code
+/// (components/api/wizard.py) and kept in flash. API_WIZARD_DATA_SIZE bytes long.
+extern const uint8_t API_WIZARD_DATA[] PROGMEM;
+
+#ifdef USE_API_WIZARD_INPUTS
+/// Where the entity id of an input is kept, found by the key the client uses for it.
+struct WizardInputEntry {
+  uint32_t key;     // FNV-1 hash of the ESPHome id of the input
+  char *entity_id;  // RAM buffer, WIZARD_ENTITY_ID_BUFFER_SIZE bytes or size, shared with the homeassistant entity
+#ifdef USE_API_WIZARD_MULTIPLE_INPUTS
+  uint16_t size;  // Buffer size of a multiple input, 0 for a single input
+#endif
+};
+
+/// The inputs of the wizard, in flash. API_WIZARD_INPUT_COUNT entries long.
+extern const WizardInputEntry API_WIZARD_INPUTS[] PROGMEM;
+
+/// Apply a WizardInputSetRequest: validate it and copy the entity id into the input's buffer. Nothing is stored
+/// across restarts, so the client sends the choices again after every connection.
+/// Returns the buffer, or nullptr when the request was ignored.
+const char *wizard_set_input(const WizardInputSetRequest &msg);
+#endif
+
+#ifdef USE_API_WIZARD_STANDALONE_INPUTS
+/// An input of the wizard that is not tied to an entity of the device. The entity ID the user picks is only ever read
+/// by lambdas, for example `id(input).entity_id()`. It lives in the same RAM buffer a linked input uses.
+class WizardInput {
+ public:
+  explicit WizardInput(const char *entity_id) : entity_id_(entity_id) {}
+  /// The Home Assistant entity ID, empty until the wizard sets one. For a multiple input this is the whole
+  /// comma separated list, which homeassistant.action data can use as it is.
+  StringRef entity_id() const { return StringRef(this->entity_id_); }
+  bool has_entity_id() const { return this->entity_id_[0] != '\0'; }
+#ifdef USE_API_WIZARD_MULTIPLE_INPUTS
+  /// The number of entity IDs in the list, 0 until the wizard sets one.
+  size_t entity_id_count() const {
+    if (!this->has_entity_id())
+      return 0;
+    size_t count = 1;
+    for (const char *p = this->entity_id_; (p = strchr(p, ',')) != nullptr; p++)
+      count++;
+    return count;
+  }
+  /// Call callback(StringRef) for each entity ID in the list, in order. The StringRef points into the list and is
+  /// not null terminated, so print it with "%.*s".
+  template<typename F> void for_each_entity_id(F &&callback) const {
+    // The device stores the list without spaces or empty entries
+    const char *start = this->entity_id_;
+    while (*start != '\0') {
+      const char *end = strchr(start, ',');
+      if (end == nullptr)
+        end = start + strlen(start);
+      callback(StringRef(start, end - start));
+      start = *end == ',' ? end + 1 : end;
+    }
+  }
+#endif
+
+ protected:
+  const char *entity_id_;
+};
+#endif
+
+}  // namespace esphome::api
+
+#endif  // USE_API_WIZARD
@@ -4,64 +4,40 @@
 #ifdef USE_API
 #ifdef USE_API_HOMEASSISTANT_SERVICES
 #include <functional>
+#include <string>
+#include <type_traits>
 #include <utility>
-#include <vector>
 #include "api_pb2.h"
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
 #include "esphome/components/json/json_util.h"
 #endif
 #include "esphome/core/automation.h"
 #include "esphome/core/helpers.h"
+#include "esphome/core/progmem.h"
 #include "esphome/core/string_ref.h"

 namespace esphome::api {

-template<typename... X> class TemplatableStringValue : public TemplatableValue<std::string, X...> {
-  // Verify that const char* uses the base class STATIC_STRING optimization (no heap allocation)
-  // rather than being wrapped in a lambda. The base class constructor for const char* is more
-  // specialized than the templated constructor here, so it should be selected.
-  static_assert(std::is_constructible_v<TemplatableValue<std::string, X...>, const char *>,
-                "Base class must have const char* constructor for STATIC_STRING optimization");
+// Converts a lambda result to the string sent to Home Assistant
+template<typename T>
+requires(!std::is_pointer_v<std::remove_cvref_t<T>>) std::string field_to_string(T &&val) {
+  return to_string(std::forward<T>(val));  // NOLINT
+}
+inline std::string field_to_string(const char *val) { return val ? std::string(val) : std::string(); }
+inline std::string field_to_string(std::string val) { return val; }
+inline std::string field_to_string(StringRef val) { return val.str(); }

- private:
-  // Helper to convert value to string - handles the case where value is already a string
-  template<typename T> static std::string value_to_string(T &&val) {
-    return to_string(std::forward<T>(val));  // NOLINT
+/// A key and value from codegen; on ESP8266 the table and its strings are in flash.
+/// The value is the constant `value`, or the result of `fn` when it is set.
+template<typename... Ts> struct HomeAssistantField {
+  const char *key;
+  const char *value;
+  std::string (*fn)(const Ts &...);
+
+  template<typename F> static constexpr HomeAssistantField from_lambda(const char *key, F /*lambda*/) {
+    return {key, nullptr, &call_lambda<F>};
  }
-
-  // Overloads for string types - needed because std::to_string doesn't support them
-  static std::string value_to_string(char *val) {
-    return val ? std::string(val) : std::string();
-  }  // For lambdas returning char* (e.g., itoa)
-  static std::string value_to_string(const char *val) { return std::string(val); }  // For lambdas returning .c_str()
-  static std::string value_to_string(const std::string &val) { return val; }
-  static std::string value_to_string(std::string &&val) { return std::move(val); }
-  static std::string value_to_string(const StringRef &val) { return val.str(); }
-  static std::string value_to_string(StringRef &&val) { return val.str(); }
-
- public:
-  TemplatableStringValue() : TemplatableValue<std::string, X...>() {}
-
-  template<typename F, enable_if_t<!is_invocable<F, X...>::value, int> = 0>
-  TemplatableStringValue(F value) : TemplatableValue<std::string, X...>(value) {}
-
-  template<typename F, enable_if_t<is_invocable<F, X...>::value, int> = 0>
-  TemplatableStringValue(F f)
-      : TemplatableValue<std::string, X...>([f](X... x) -> std::string { return value_to_string(f(x...)); }) {}
-};
-
-template<typename... Ts> class TemplatableKeyValuePair {
- public:
-  // Default constructor needed for FixedVector::emplace_back()
-  TemplatableKeyValuePair() = default;
-
-  // Keys are always string literals from YAML dictionary keys (e.g., "code", "event")
-  // and never templatable values or lambdas. Only the value parameter can be a lambda/template.
-  // Using const char* avoids std::string heap allocation - keys remain in flash.
-  template<typename T> TemplatableKeyValuePair(const char *key, T value) : key(key), value(value) {}
-
-  const char *key{nullptr};
-  TemplatableStringValue<Ts...> value;
+  template<typename F> static std::string call_lambda(const Ts &...x) { return field_to_string(F{}(x...)); }
 };

 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
@@ -106,45 +82,20 @@ template<typename... Ts> using ActionResponseCallback = std::function<void(const

 template<typename... Ts> class HomeAssistantServiceCallAction final : public Action<Ts...> {
 public:
-  explicit HomeAssistantServiceCallAction(APIServer *parent, bool is_event) : parent_(parent) {
+  using Field = HomeAssistantField<Ts...>;
+
+  /// `fields` is a codegen table: the action or event name (no key), then the data, data_template
+  /// and variables entries.
+  HomeAssistantServiceCallAction(APIServer *parent, bool is_event, const Field *fields, uint8_t data_count,
+                                 uint8_t data_template_count, uint8_t variables_count)
+      : parent_(parent),
+        fields_(fields),
+        data_count_(data_count),
+        data_template_count_(data_template_count),
+        variables_count_(variables_count) {
    this->flags_.is_event = is_event;
  }

-  template<typename T> void set_service(T service) { this->service_ = service; }
-
-  // Initialize FixedVector members - called from Python codegen with compile-time known sizes.
-  // Must be called before any add_* methods; capacity must match the number of subsequent add_* calls.
-  void init_data(size_t count) { this->data_.init(count); }
-  void init_data_template(size_t count) { this->data_template_.init(count); }
-  void init_variables(size_t count) { this->variables_.init(count); }
-
-  // Keys are always string literals from the Python code generation (e.g., cg.add(var.add_data("tag_id", templ))).
-  // The value parameter can be a lambda/template, but keys are never templatable.
-  // Using const char* for keys avoids std::string heap allocation - keys remain in flash.
-  template<typename V> void add_data(const char *key, V &&value) {
-    this->add_kv_(this->data_, key, std::forward<V>(value));
-  }
-  template<typename V> void add_data_template(const char *key, V &&value) {
-    this->add_kv_(this->data_template_, key, std::forward<V>(value));
-  }
-  template<typename V> void add_variable(const char *key, V &&value) {
-    this->add_kv_(this->variables_, key, std::forward<V>(value));
-  }
-
-#ifdef USE_ESP8266
-  // On ESP8266, ESPHOME_F() returns __FlashStringHelper* (PROGMEM pointer).
-  // Store as const char* — populate_service_map copies from PROGMEM at play() time.
-  template<typename V> void add_data(const __FlashStringHelper *key, V &&value) {
-    this->add_kv_(this->data_, reinterpret_cast<const char *>(key), std::forward<V>(value));
-  }
-  template<typename V> void add_data_template(const __FlashStringHelper *key, V &&value) {
-    this->add_kv_(this->data_template_, reinterpret_cast<const char *>(key), std::forward<V>(value));
-  }
-  template<typename V> void add_variable(const __FlashStringHelper *key, V &&value) {
-    this->add_kv_(this->variables_, reinterpret_cast<const char *>(key), std::forward<V>(value));
-  }
-#endif
-
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
  template<typename T> void set_response_template(T response_template) {
    this->response_template_ = response_template;
@@ -162,19 +113,61 @@ template<typename... Ts> class HomeAssistantServiceCallAction final : public Act
 #endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES

  void play(const Ts &...x) override {
+    const Field *fields = this->fields_;
+    const size_t total = 1 + this->data_count_ + this->data_template_count_ + this->variables_count_;
+
+    // Lambda results, and on ESP8266 the RAM copies of the flash strings, must live until the send
+    size_t lambda_count = 0;
+#ifdef USE_ESP8266
+    size_t flash_len = 0;
+#endif
+    for (size_t i = 0; i < total; i++) {
+      lambda_count += fields[i].fn != nullptr;
+#ifdef USE_ESP8266
+      if (fields[i].fn == nullptr)
+        flash_len += ESPHOME_strlen_P(fields[i].value);
+      if (fields[i].key != nullptr)
+        flash_len += ESPHOME_strlen_P(fields[i].key);
+#endif
+    }
+    FixedVector<std::string> results;
+    results.init(lambda_count);
+#ifdef USE_ESP8266
+    SmallBufferWithHeapFallback<128, char> flash_copy(flash_len);
+    char *cursor = flash_copy.get();
+#endif
+    auto string_ref = [&](const char *str) {
+#ifdef USE_ESP8266
+      size_t len = ESPHOME_strlen_P(str);
+      memcpy_P(cursor, str, len);
+      StringRef ref(cursor, len);
+      cursor += len;
+      return ref;
+#else
+      return StringRef(str);
+#endif
+    };
+    auto value_ref = [&](const Field &field) {
+      if (field.fn == nullptr)
+        return string_ref(field.value);
+      results.push_back(field.fn(x...));
+      return StringRef(results.back());
+    };
+    auto fill = [&](FixedVector<HomeassistantServiceMap> &dest, uint8_t count) {
+      dest.init(count);
+      for (uint8_t i = 0; i < count; i++, fields++) {
+        auto &kv = dest.emplace_back();
+        kv.key = string_ref(fields->key);
+        kv.value = value_ref(*fields);
+      }
+    };
+
    HomeassistantActionRequest resp;
-    std::string service_value = this->service_.value(x...);
-    resp.service = StringRef(service_value);
+    resp.service = value_ref(*fields++);
    resp.is_event = this->flags_.is_event;
-
-    // Local storage for lambda-evaluated strings - lives until after send
-    FixedVector<std::string> data_storage;
-    FixedVector<std::string> data_template_storage;
-    FixedVector<std::string> variables_storage;
-
-    this->populate_service_map(resp.data, this->data_, data_storage, x...);
-    this->populate_service_map(resp.data_template, this->data_template_, data_template_storage, x...);
-    this->populate_service_map(resp.variables, this->variables_, variables_storage, x...);
+    fill(resp.data, this->data_count_);
+    fill(resp.data_template, this->data_template_count_);
+    fill(resp.variables, this->variables_count_);

 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
@@ -223,90 +216,26 @@ template<typename... Ts> class HomeAssistantServiceCallAction final : public Act
  }

 protected:
-  // Helper to add key-value pairs to FixedVectors
-  // Keys are always string literals (const char*), values can be lambdas/templates
-  template<typename V> void add_kv_(FixedVector<TemplatableKeyValuePair<Ts...>> &vec, const char *key, V &&value) {
-    auto &kv = vec.emplace_back();
-    kv.key = key;
-    kv.value = std::forward<V>(value);
-  }
-
-  template<typename VectorType, typename SourceType>
-  static void populate_service_map(VectorType &dest, SourceType &source, FixedVector<std::string> &value_storage,
-                                   Ts... x) {
-    dest.init(source.size());
-
-#ifdef USE_ESP8266
-    // On ESP8266, all static strings from codegen are FLASH_STRING (PROGMEM),
-    // so is_static_string() is always false — the zero-copy STATIC_STRING fast
-    // path from the non-ESP8266 branch cannot trigger. We copy all keys and
-    // values unconditionally: keys via _P functions (may be in PROGMEM), values
-    // via value() which handles FLASH_STRING internally.
-    value_storage.init(source.size() * 2);
-
-    for (auto &it : source) {
-      auto &kv = dest.emplace_back();
-
-      // Key: copy from possible PROGMEM
-      {
-        size_t key_len = strlen_P(it.key);
-        value_storage.push_back(std::string(key_len, '\0'));
-        memcpy_P(value_storage.back().data(), it.key, key_len);
-        kv.key = StringRef(value_storage.back());
-      }
-
-      // Value: value() handles FLASH_STRING via _P functions internally
-      value_storage.push_back(it.value.value(x...));
-      kv.value = StringRef(value_storage.back());
-    }
-#else
-    // On non-ESP8266, strings are directly readable from flash-mapped memory.
-    // Count non-static strings to allocate exact storage needed.
-    size_t lambda_count = 0;
-    for (const auto &it : source) {
-      if (!it.value.is_static_string()) {
-        lambda_count++;
-      }
-    }
-    value_storage.init(lambda_count);
-
-    for (auto &it : source) {
-      auto &kv = dest.emplace_back();
-      kv.key = StringRef(it.key);
-
-      if (it.value.is_static_string()) {
-        // Static string — pointer directly readable, zero allocation
-        kv.value = StringRef(it.value.get_static_string());
-      } else {
-        // Lambda — evaluate and store result
-        value_storage.push_back(it.value.value(x...));
-        kv.value = StringRef(value_storage.back());
-      }
-    }
-#endif
-  }
-
  APIServer *parent_;
-  TemplatableStringValue<Ts...> service_{};
-  FixedVector<TemplatableKeyValuePair<Ts...>> data_;
-  FixedVector<TemplatableKeyValuePair<Ts...>> data_template_;
-  FixedVector<TemplatableKeyValuePair<Ts...>> variables_;
-#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
-#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
-  TemplatableStringValue<Ts...> response_template_{""};
-  Trigger<JsonObjectConst, Ts...> success_trigger_with_response_;
-#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
-  Trigger<Ts...> success_trigger_;
-  Trigger<std::string, Ts...> error_trigger_;
-#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
-
+  const Field *fields_;
+  uint8_t data_count_;
+  uint8_t data_template_count_;
+  uint8_t variables_count_;
  struct Flags {
    uint8_t is_event : 1;
    uint8_t wants_status : 1;
    uint8_t wants_response : 1;
    uint8_t has_response_template : 1;
-    uint8_t reserved : 5;
+    uint8_t reserved : 4;
  } flags_{0};
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  TemplatableValue<std::string, Ts...> response_template_{};
+  Trigger<JsonObjectConst, Ts...> success_trigger_with_response_;
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  Trigger<Ts...> success_trigger_;
+  Trigger<std::string, Ts...> error_trigger_;
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
 };

 }  // namespace esphome::api
@@ -119,7 +119,7 @@ uint32_t ProtoDecodableMessage::count_repeated_field(const uint8_t *buffer, size
 }

 // Single-pass encode for repeated submessage elements (non-template core).
-// Writes field tag, reserves 1 byte for length varint, encodes the submessage body,
+// Reserves 1 byte for length varint, encodes the submessage body,
 // then backpatches the actual length. For the common case (body < 128 bytes), this is
 // just a single byte write with no memmove — all current repeated submessage types
 // (BLE advertisements at ~47B, GATT descriptors at ~24B, service args, etc.) take
@@ -143,51 +143,34 @@ uint32_t ProtoDecodableMessage::count_repeated_field(const uint8_t *buffer, size
 //
 //   After writing 2-byte varint at len_pos:
 //   [tag][v1][v2][body ..... body]
-//                                ^-- pos_ = element end, within buffer
-void ProtoWriteBuffer::encode_sub_message(uint32_t field_id, const void *value,
-                                          uint8_t *(*encode_fn)(const void *,
-                                                                ProtoWriteBuffer &PROTO_ENCODE_DEBUG_PARAM)) {
-  this->encode_field_raw(field_id, 2);
-  // Reserve 1 byte for length varint (optimistic: submessage < 128 bytes)
-  uint8_t *len_pos = this->pos_;
-  this->debug_check_bounds_(1);
-  this->pos_++;
-  uint8_t *body_start = this->pos_;
-  this->pos_ = encode_fn(value, *this PROTO_ENCODE_DEBUG_INIT(this->buffer_));
-  uint32_t body_size = static_cast<uint32_t>(this->pos_ - body_start);
-  if (body_size < 128) [[likely]] {
+//                                ^-- returned cursor = element end, within buffer
+uint8_t *ProtoEncode::encode_sub_message_body(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, const void *value,
+                                              ProtoEncodeFn encode_fn) {
+  // Reserve 1 byte for the length varint (optimistic: submessage < 128 bytes)
+  uint8_t *len_pos = pos;
+  PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
+  uint8_t *body_start = pos + 1;
+  uint8_t *after_body = encode_fn(value, body_start PROTO_ENCODE_DEBUG_ARG);
+  uint32_t body_size = static_cast<uint32_t>(after_body - body_start);
+  if (body_size < VARINT_MAX_1_BYTE) [[likely]] {
    // Common case: 1-byte varint, just backpatch
    *len_pos = static_cast<uint8_t>(body_size);
-    return;
+    return after_body;
  }
-  // Compute extra bytes needed for varint beyond the 1 already reserved
+  // Shift the body forward to make room for the extra length varint bytes
  uint8_t extra = ProtoSize::varint(body_size) - 1;
-  // Shift body forward to make room for the extra varint bytes
-  this->debug_check_bounds_(extra);
+  PROTO_ENCODE_CHECK_BOUNDS(after_body, extra);
  std::memmove(body_start + extra, body_start, body_size);
-  uint8_t *end = this->pos_ + extra;
  // Write the full varint at len_pos
-  this->pos_ = len_pos;
-  this->encode_varint_raw(body_size);
-  this->pos_ = end;
+  (void) encode_varint_raw_loop(len_pos PROTO_ENCODE_DEBUG_ARG, body_size);
+  return after_body + extra;
 }

 // Non-template core for encode_optional_sub_message.
-void ProtoWriteBuffer::encode_optional_sub_message(uint32_t field_id, uint32_t nested_size, const void *value,
-                                                   uint8_t *(*encode_fn)(const void *,
-                                                                         ProtoWriteBuffer &PROTO_ENCODE_DEBUG_PARAM)) {
-  if (nested_size == 0)
-    return;
-  this->encode_field_raw(field_id, 2);
-  this->encode_varint_raw(nested_size);
-#ifdef ESPHOME_DEBUG_API
-  uint8_t *start = this->pos_;
-  this->pos_ = encode_fn(value, *this PROTO_ENCODE_DEBUG_INIT(this->buffer_));
-  if (static_cast<uint32_t>(this->pos_ - start) != nested_size)
-    this->debug_check_encode_size_(field_id, nested_size, this->pos_ - start);
-#else
-  this->pos_ = encode_fn(value, *this PROTO_ENCODE_DEBUG_INIT(this->buffer_));
-#endif
+uint8_t *ProtoEncode::encode_sized_sub_message_body(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                    uint32_t nested_size, const void *value, ProtoEncodeFn encode_fn) {
+  pos = encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, nested_size);
+  return encode_fn(value, pos PROTO_ENCODE_DEBUG_ARG);
 }

 #ifdef ESPHOME_DEBUG_API
@@ -201,6 +184,14 @@ void proto_check_encode_end(const uint8_t *end, const uint8_t *expected) {
  ESP_LOGE(TAG, "Proto encode ended %td bytes off the calculated size", end - expected);
  abort();
 }
+void proto_check_sub_message_size(uint32_t field_id, uint32_t expected, const uint8_t *len_pos, const uint8_t *end) {
+  ptrdiff_t actual = end - (len_pos + ProtoSize::varint(expected));
+  if (actual == static_cast<ptrdiff_t>(expected))
+    return;
+  ESP_LOGE(TAG, "encode_message: size mismatch for field %" PRIu32 ": calculated=%" PRIu32 " actual=%td", field_id,
+           expected, actual);
+  abort();
+}
 void ProtoWriteBuffer::debug_check_bounds_(size_t bytes, const char *caller) {
  if (this->pos_ + bytes > this->buffer_->data() + this->buffer_->size()) {
    ESP_LOGE(TAG, "ProtoWriteBuffer bounds check failed in %s: bytes=%zu offset=%td buf_size=%zu", caller, bytes,
@@ -208,11 +199,6 @@ void ProtoWriteBuffer::debug_check_bounds_(size_t bytes, const char *caller) {
    abort();
  }
 }
-void ProtoWriteBuffer::debug_check_encode_size_(uint32_t field_id, uint32_t expected, ptrdiff_t actual) {
-  ESP_LOGE(TAG, "encode_message: size mismatch for field %" PRIu32 ": calculated=%" PRIu32 " actual=%td", field_id,
-           expected, actual);
-  abort();
-}

 #endif

@@ -3,6 +3,7 @@
 #include "api_pb2_defines.h"
 #include "api_buffer.h"
 #include "esphome/core/component.h"
+#include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include "esphome/core/progmem.h"
@@ -56,22 +57,25 @@ inline constexpr int64_t decode_zigzag64(uint64_t value) {
  return (value & 1) ? static_cast<int64_t>(~(value >> 1)) : static_cast<int64_t>(value >> 1);
 }

-/// Count number of varints in a packed buffer
-inline uint16_t count_packed_varints(const uint8_t *data, size_t len) {
-  uint16_t count = 0;
-  while (len > 0) {
-    // Skip varint bytes until we find one without continuation bit
-    while (len > 0 && (*data & 0x80)) {
-      data++;
-      len--;
-    }
-    if (len > 0) {
-      data++;
-      len--;
-      count++;
+/// Count varints in a packed buffer: len minus bytes with the continuation bit, summed a word at a time.
+/// Word is a template parameter so tests can cover the 32-bit path on a 64-bit host.
+template<typename Word = size_t> inline uint16_t count_packed_varints(const uint8_t *data, size_t len) {
+  constexpr size_t word_size = sizeof(Word);
+  constexpr Word lane_ones = ~Word{0} / 0xFF;  // 0x01..01
+  const uint8_t *end = data + len;
+  size_t continuations = 0;
+  while (data != end) {
+    // Unaligned word loads fault on Xtensa
+    if ((reinterpret_cast<uintptr_t>(data) & (word_size - 1)) == 0 && static_cast<size_t>(end - data) >= word_size) {
+      Word word;
+      memcpy(&word, __builtin_assume_aligned(data, word_size), word_size);
+      continuations += (((word >> 7) & lane_ones) * lane_ones) >> (word_size * 8 - 8);
+      data += word_size;
+    } else {
+      continuations += *data++ >> 7;
    }
  }
-  return count;
+  return static_cast<uint16_t>(len - continuations);
 }

 /// Encode a varint directly into a pre-allocated buffer.
@@ -228,6 +232,8 @@ void proto_check_bounds_failed(const uint8_t *pos, size_t bytes, const uint8_t *
 /// Aborts unless an encode body ended exactly where calculate_size() promised. A plain check rather than
 /// assert(), so NDEBUG cannot switch it off.
 void proto_check_encode_end(const uint8_t *end, const uint8_t *expected);
+/// Aborts unless a sized sub-message (length prefix at len_pos) ended where its calculated size said.
+void proto_check_sub_message_size(uint32_t field_id, uint32_t expected, const uint8_t *len_pos, const uint8_t *end);
 #else
 #define PROTO_ENCODE_DEBUG_PARAM
 #define PROTO_ENCODE_DEBUG_ARG
@@ -260,21 +266,6 @@ class ProtoWriteBuffer {
   * Following https://protobuf.dev/programming-guides/encoding/#structure
   */
  void encode_field_raw(uint32_t field_id, uint32_t type) { this->encode_varint_raw(proto_tag(field_id, type)); }
-  /// Single-pass encode for repeated submessage elements.
-  /// Thin template wrapper; all buffer work is in the non-template core.
-  template<typename T> void encode_sub_message(uint32_t field_id, const T &value);
-  /// Encode an optional singular submessage field — skips if empty.
-  /// Thin template wrapper; all buffer work is in the non-template core.
-  template<typename T> void encode_optional_sub_message(uint32_t field_id, const T &value);
-
-  // NOLINTBEGIN(readability-identifier-naming)
-  // Non-template core for encode_sub_message — backpatch approach.
-  void encode_sub_message(uint32_t field_id, const void *value,
-                          uint8_t *(*encode_fn)(const void *, ProtoWriteBuffer &PROTO_ENCODE_DEBUG_PARAM));
-  // Non-template core for encode_optional_sub_message.
-  void encode_optional_sub_message(uint32_t field_id, uint32_t nested_size, const void *value,
-                                   uint8_t *(*encode_fn)(const void *, ProtoWriteBuffer &PROTO_ENCODE_DEBUG_PARAM));
-  // NOLINTEND(readability-identifier-naming)
  APIBuffer *get_buffer() const { return buffer_; }
  uint8_t *get_pos() const { return pos_; }
  void set_pos(uint8_t *pos) { pos_ = pos; }
@@ -285,7 +276,6 @@ class ProtoWriteBuffer {

 #ifdef ESPHOME_DEBUG_API
  void debug_check_bounds_(size_t bytes, const char *caller = __builtin_FUNCTION());
-  void debug_check_encode_size_(uint32_t field_id, uint32_t expected, ptrdiff_t actual);
 #else
  void debug_check_bounds_([[maybe_unused]] size_t bytes) {}
 #endif
@@ -310,6 +300,9 @@ class ProtoWriteBuffer {
 constexpr uint32_t VARINT_MAX_1_BYTE = 1 << 7;   // 128
 constexpr uint32_t VARINT_MAX_2_BYTE = 1 << 14;  // 16384

+/// Generated encode body: writes the fields at pos, returns the cursor past them.
+using ProtoEncodeFn = uint8_t *(*) (const void *, uint8_t *PROTO_ENCODE_DEBUG_PARAM);
+
 /// Static encode helpers for the generated encode bodies. Each takes the write cursor by value and
 /// returns it advanced, so outlined calls at -Os chain through the return register instead of a
 /// stack slot. Helpers without a _force suffix skip fields holding the proto3 default.
@@ -473,6 +466,21 @@ class ProtoEncode {
                                                          uint32_t field_id, const uint8_t *data, size_t len) {
    return encode_string_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, reinterpret_cast<const char *>(data), len);
  }
+  /// encode_bytes for data in flash (PROGMEM), which ESP8266 can only read with progmem_memcpy.
+  [[nodiscard]] static inline uint8_t *encode_progmem_bytes(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                            uint32_t field_id, const uint8_t *data, size_t len) {
+    if (len == 0)
+      return pos;
+    return encode_progmem_bytes_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, data, len);
+  }
+  [[nodiscard]] static inline uint8_t *encode_progmem_bytes_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                                  uint32_t field_id, const uint8_t *data, size_t len) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);  // type 2: Length-delimited
+    pos = encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, len);
+    PROTO_ENCODE_CHECK_BOUNDS(pos, len);
+    progmem_memcpy(pos, data, len);
+    return pos + len;
+  }
  [[nodiscard]] static inline uint8_t *encode_uint32_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
                                                           uint32_t field_id, uint32_t value) {
    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
@@ -572,22 +580,36 @@ class ProtoEncode {
                                                           uint32_t field_id, int64_t value) {
    return encode_uint64_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag64(value));
  }
-  /// Sub-message encoding: sync pos to buffer, delegate, read the cursor back.
+  /// Repeated sub-message element; the constant tag is written inline.
  template<typename T>
  [[nodiscard]] static inline uint8_t *encode_sub_message(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
-                                                          ProtoWriteBuffer &buffer, uint32_t field_id, const T &value) {
-    buffer.set_pos(pos);
-    buffer.encode_sub_message(field_id, value);
-    return buffer.get_pos();
+                                                          uint32_t field_id, const T &value) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);
+    return encode_sub_message_body(pos PROTO_ENCODE_DEBUG_ARG, &value, &T::encode_msg);
  }
+  /// Singular sub-message field, skipped when it encodes to nothing.
  template<typename T>
  [[nodiscard]] static inline uint8_t *encode_optional_sub_message(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
-                                                                   ProtoWriteBuffer &buffer, uint32_t field_id,
-                                                                   const T &value) {
-    buffer.set_pos(pos);
-    buffer.encode_optional_sub_message(field_id, value);
-    return buffer.get_pos();
+                                                                   uint32_t field_id, const T &value) {
+    uint32_t nested_size = T::calc_size_msg(&value);
+    if (nested_size == 0)
+      return pos;
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);
+#ifdef ESPHOME_DEBUG_API
+    uint8_t *end = encode_sized_sub_message_body(pos PROTO_ENCODE_DEBUG_ARG, nested_size, &value, &T::encode_msg);
+    proto_check_sub_message_size(field_id, nested_size, pos, end);
+    return end;
+#else
+    return encode_sized_sub_message_body(pos, nested_size, &value, &T::encode_msg);
+#endif
  }
+  /// Length and body, length backpatched after the body is written.
+  [[nodiscard]] static uint8_t *encode_sub_message_body(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                        const void *value, ProtoEncodeFn encode_fn);
+  /// Length and body for a precomputed size.
+  [[nodiscard]] static uint8_t *encode_sized_sub_message_body(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                              uint32_t nested_size, const void *value,
+                                                              ProtoEncodeFn encode_fn);

 private:
  /// Unaligned little endian store of four bytes: byte stores where the outlined helper lives (ESP-IDF, ARM
@@ -701,9 +723,7 @@ class ProtoMessage {
 public:
  // Non-virtual defaults for messages with no fields; generated classes hide all four. The
  // static encode_msg/calc_size_msg take const void * so &T::encode_msg needs no thunk.
-  static uint8_t *encode_msg(const void *self, ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) {
-    return buffer.get_pos();
-  }
+  static uint8_t *encode_msg(const void *self, uint8_t *pos PROTO_ENCODE_DEBUG_PARAM) { return pos; }
  static uint32_t calc_size_msg(const void *self) { return 0; }
  uint8_t *encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const { return buffer.get_pos(); }
  uint32_t calculate_size() const { return 0; }
@@ -957,18 +977,6 @@ class ProtoSize {
  }
 };

-// Implementation of methods that depend on ProtoSize being fully defined
-
-// Thin template wrapper; delegates to non-template core in proto.cpp.
-template<typename T> inline void ProtoWriteBuffer::encode_sub_message(uint32_t field_id, const T &value) {
-  this->encode_sub_message(field_id, &value, &T::encode_msg);
-}
-
-// Thin template wrapper; delegates to non-template core.
-template<typename T> inline void ProtoWriteBuffer::encode_optional_sub_message(uint32_t field_id, const T &value) {
-  this->encode_optional_sub_message(field_id, T::calc_size_msg(&value), &value, &T::encode_msg);
-}
-
 template<typename T> const char *proto_enum_to_string(T value);

 // ProtoService removed — its methods were inlined into APIConnection.
@@ -0,0 +1,498 @@
+"""The device wizard of the api component: schema, validation and code generation.
+
+Home Assistant shows the wizard when the device is added. See api_wizard.h for the C++ side.
+"""
+
+from collections.abc import Callable
+import importlib
+import json
+from typing import Any
+
+from esphome import automation
+import esphome.codegen as cg
+from esphome.components.const import CONF_DESCRIPTION
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_DEVICE_CLASS,
+    CONF_DEVICE_ID,
+    CONF_DOMAIN,
+    CONF_ENTITY_ID,
+    CONF_ID,
+    CONF_INTERNAL,
+    CONF_MAX_LENGTH,
+    CONF_MULTIPLE,
+    CONF_NAME,
+    CONF_PAGES,
+    CONF_PLATFORM,
+    CONF_TARGET,
+)
+from esphome.core import CORE, ID
+import esphome.final_validate as fv
+from esphome.helpers import (
+    fnv1_hash,
+    fnv1_hash_object_id,
+    fnv1a_32bit_hash,
+    zstd_module,
+)
+from esphome.types import ConfigType
+
+API_DOMAIN = "api"
+
+CONF_ENTITIES = "entities"
+CONF_ENTITY = "entity"
+CONF_INPUTS = "inputs"
+CONF_INTEGRATION = "integration"
+CONF_SUPPORTED_FEATURES = "supported_features"
+CONF_TITLE = "title"
+CONF_WIZARD = "wizard"
+
+_API = cg.esphome_ns.namespace("api")
+WizardInput = _API.class_("WizardInput")
+
+WIZARD_ENTITY_ID_BUFFER_SIZE = (
+    256  # api_wizard.h; Home Assistant entity IDs are at most 255 bytes
+)
+WIZARD_ENTITY_ID_MAX_LENGTH = WIZARD_ENTITY_ID_BUFFER_SIZE - 1
+# The value of a multiple input fits one WizardInputSetRequest, which the device accepts up to 8 KiB on ESP8266;
+# api.proto max_data_length documents the same value
+WIZARD_MULTIPLE_MAX_LENGTH = 4095
+# One API message must fit APIBuffer::MAX_SIZE (65535) together with the largest frame header (7 bytes,
+# Noise) and footer (16 bytes, Noise MAC)
+WIZARD_RESPONSE_MAX_SIZE = 65535 - 7 - 16
+# Version of the JSON the wizard is sent as, see wizard_document()
+WIZARD_JSON_VERSION = 1
+# zstd level the JSON is compressed with. Output is deterministic for a given zstd version.
+WIZARD_ZSTD_LEVEL = 19
+
+# Wizard string limits; api.proto documents the same values
+WIZARD_TITLE_MAX_LENGTH = 127
+WIZARD_DESCRIPTION_MAX_LENGTH = 255
+WIZARD_FILTER_MAX_LENGTH = 63
+WIZARD_SUPPORTED_FEATURE_MAX_LENGTH = 127
+
+
+def _wizard_text(max_length: int) -> Callable[[Any], str]:
+    """A string passed to Home Assistant verbatim, so it may be a [%key:...%] translation placeholder."""
+    return cv.All(cv.string_strict, cv.Length(max=max_length))
+
+
+def _wizard_strings(max_length: int) -> Callable[[Any], list[str]]:
+    """A single string or a list of strings, always validated to a non-empty list."""
+    return cv.All(
+        cv.ensure_list(cv.All(cv.string_strict, cv.Length(min=1, max=max_length))),
+        cv.Length(min=1),
+    )
+
+
+# Mirrors Home Assistant's EntityFilterSelectorConfig
+WIZARD_ENTITY_FILTER_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.Optional(CONF_INTEGRATION): cv.All(
+                cv.string_strict, cv.Length(min=1, max=WIZARD_FILTER_MAX_LENGTH)
+            ),
+            cv.Optional(CONF_DOMAIN): _wizard_strings(WIZARD_FILTER_MAX_LENGTH),
+            cv.Optional(CONF_DEVICE_CLASS): _wizard_strings(WIZARD_FILTER_MAX_LENGTH),
+            cv.Optional(CONF_SUPPORTED_FEATURES): _wizard_strings(
+                WIZARD_SUPPORTED_FEATURE_MAX_LENGTH
+            ),
+        }
+    ),
+    cv.has_at_least_one_key(
+        CONF_INTEGRATION, CONF_DOMAIN, CONF_DEVICE_CLASS, CONF_SUPPORTED_FEATURES
+    ),
+)
+
+WIZARD_ENTITY_SCHEMA = cv.Schema(
+    {
+        cv.Required(CONF_ID): cv.use_id(cg.EntityBase),
+        cv.Optional(CONF_DESCRIPTION): _wizard_text(WIZARD_DESCRIPTION_MAX_LENGTH),
+    }
+)
+
+
+def _validate_multiple(conf: ConfigType) -> ConfigType:
+    if conf[CONF_MULTIPLE] and CONF_ENTITY in conf:
+        raise cv.Invalid(
+            "A linked input follows the state of exactly one Home Assistant entity, so multiple "
+            "is only for standalone inputs (id)",
+            path=[CONF_MULTIPLE],
+        )
+    if CONF_MAX_LENGTH in conf and not conf[CONF_MULTIPLE]:
+        raise cv.Invalid(
+            "max_length only applies to an input with multiple: true",
+            path=[CONF_MAX_LENGTH],
+        )
+    return conf
+
+
+# An input is either standalone (id declares a new WizardInput) or linked to a homeassistant entity that has no
+# entity_id of its own: Home Assistant sets it
+WIZARD_INPUT_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.Optional(CONF_ID): cv.declare_id(WizardInput),
+            cv.Optional(CONF_ENTITY): cv.use_id(cg.EntityBase),
+            cv.Optional(CONF_DESCRIPTION): _wizard_text(WIZARD_DESCRIPTION_MAX_LENGTH),
+            cv.Optional(CONF_MULTIPLE, default=False): cv.boolean,
+            cv.Optional(CONF_MAX_LENGTH): cv.int_range(
+                min=WIZARD_ENTITY_ID_MAX_LENGTH, max=WIZARD_MULTIPLE_MAX_LENGTH
+            ),
+            cv.Optional(CONF_TARGET): cv.Schema(
+                {
+                    cv.Required(CONF_ENTITY): cv.All(
+                        cv.ensure_list(WIZARD_ENTITY_FILTER_SCHEMA), cv.Length(min=1)
+                    ),
+                }
+            ),
+        }
+    ),
+    cv.has_exactly_one_key(CONF_ID, CONF_ENTITY),
+    _validate_multiple,
+)
+
+WIZARD_PAGE_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.Optional(CONF_TITLE): _wizard_text(WIZARD_TITLE_MAX_LENGTH),
+            cv.Optional(CONF_DESCRIPTION): _wizard_text(WIZARD_DESCRIPTION_MAX_LENGTH),
+            cv.Optional(CONF_ENTITIES): cv.All(
+                cv.ensure_list(WIZARD_ENTITY_SCHEMA), cv.Length(min=1)
+            ),
+            cv.Optional(CONF_INPUTS): cv.All(
+                cv.ensure_list(WIZARD_INPUT_SCHEMA), cv.Length(min=1)
+            ),
+        }
+    ),
+    cv.has_at_least_one_key(CONF_ENTITIES, CONF_INPUTS),
+)
+
+
+def _wizard_inputs(wizard: ConfigType) -> list[ConfigType]:
+    return [conf for page in wizard[CONF_PAGES] for conf in page.get(CONF_INPUTS, [])]
+
+
+def _wizard_input_id(conf: ConfigType) -> ID:
+    """The ID that names an input: the one a standalone input declares, or its linked entity."""
+    return conf[CONF_ID] if CONF_ID in conf else conf[CONF_ENTITY]
+
+
+def _validate_unique_wizard_inputs(wizard: ConfigType) -> ConfigType:
+    """An input is identified on the wire by a hash of its ID, so IDs and hashes must be unique."""
+    seen: dict[int, str] = {}
+    for conf in _wizard_inputs(wizard):
+        input_id = _wizard_input_id(conf).id
+        if (key := fnv1_hash(input_id)) in seen:
+            if seen[key] == input_id:
+                raise cv.Invalid(f"Wizard input '{input_id}' is used more than once")
+            raise cv.Invalid(
+                f"Wizard inputs '{seen[key]}' and '{input_id}' have the same hash, rename one"
+            )
+        seen[key] = input_id
+    return wizard
+
+
+WIZARD_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.Required(CONF_PAGES): cv.All(
+                cv.ensure_list(WIZARD_PAGE_SCHEMA), cv.Length(min=1)
+            ),
+        }
+    ),
+    _validate_unique_wizard_inputs,
+)
+
+# Platforms of the homeassistant component that a wizard input can stand for
+WIZARD_INPUT_DOMAINS = (
+    "binary_sensor",
+    "button",
+    "number",
+    "select",
+    "sensor",
+    "switch",
+    "text",
+    "text_sensor",
+)
+# Platforms that act on one family of Home Assistant domains, which the input's filters must stay within
+WIZARD_DOMAIN_LIMITED_PLATFORMS = ("button", "number", "select", "switch", "text")
+
+
+def wizard_input_ids(api_config: ConfigType) -> set[str]:
+    """The IDs of the entities that are linked inputs of the wizard in the given api config."""
+    if (wizard := api_config.get(CONF_WIZARD)) is None:
+        return set()
+    return {
+        conf[CONF_ENTITY].id for conf in _wizard_inputs(wizard) if CONF_ENTITY in conf
+    }
+
+
+def _wizard_buffer_name(entity_id: ID) -> str:
+    return f"api_wizard_input_{entity_id.id}"
+
+
+def wizard_input_buffer(entity_id: ID) -> str | None:
+    """Name of the RAM buffer holding the Home Assistant entity ID of a wizard input.
+
+    Returns None when the entity is not an input of the wizard. The buffer is defined by the api
+    codegen, and the homeassistant entity of the input is given it in place of a constant.
+    """
+    if entity_id.id not in wizard_input_ids(CORE.config.get(API_DOMAIN, {})):
+        return None
+    return _wizard_buffer_name(entity_id)
+
+
+def _wizard_input_declaration(
+    config: fv.FinalValidateConfig, entity_id: ID
+) -> tuple[str, ConfigType]:
+    """The domain (like sensor) and the config an input ID is declared in."""
+    path = config.get_path_for_id(entity_id)[:-1]
+    return path[0], config.get_config_for_path(path)
+
+
+def _wizard_input_filters(
+    conf: ConfigType, config: fv.FinalValidateConfig
+) -> list[ConfigType]:
+    """The entity filters of an input, with the defaults of a domain limited linked platform."""
+    if (filters := conf.get(CONF_TARGET, {}).get(CONF_ENTITY)) is not None:
+        return filters
+    if CONF_ENTITY in conf:
+        domain, _ = _wizard_input_declaration(config, conf[CONF_ENTITY])
+        if domains := _wizard_default_domains(domain):
+            return [{CONF_DOMAIN: domains}]
+    return []
+
+
+def _wizard_defines(wizard: ConfigType) -> set[str]:
+    """The defines for the parts of the wizard the configuration uses, so the rest is not compiled."""
+    inputs = _wizard_inputs(wizard)
+    defines = {"USE_API_WIZARD"}
+    if inputs:
+        defines.add("USE_API_WIZARD_INPUTS")
+    if any(CONF_ENTITY in conf for conf in inputs):
+        defines.add("USE_API_WIZARD_LINKED_INPUTS")
+    if any(CONF_ID in conf for conf in inputs):
+        defines.add("USE_API_WIZARD_STANDALONE_INPUTS")
+    if any(conf.get(CONF_MULTIPLE) for conf in inputs):
+        defines.add("USE_API_WIZARD_MULTIPLE_INPUTS")
+    return defines
+
+
+def _wizard_default_domains(domain: str) -> list[str] | None:
+    """The domains Home Assistant entities can be picked from when the input sets no target."""
+    if domain in WIZARD_DOMAIN_LIMITED_PLATFORMS:
+        platform = importlib.import_module(f"esphome.components.homeassistant.{domain}")
+        return list(platform.SUPPORTED_DOMAINS)
+    return None
+
+
+def _validate_wizard_input(conf: ConfigType) -> ConfigType:
+    if CONF_ENTITY not in conf:
+        return conf
+    domain, declaration = _wizard_input_declaration(
+        fv.full_config.get(), conf[CONF_ENTITY]
+    )
+    if (
+        declaration.get(CONF_PLATFORM) != "homeassistant"
+        or domain not in WIZARD_INPUT_DOMAINS
+    ):
+        raise cv.Invalid(
+            f"Wizard input '{conf[CONF_ENTITY].id}' must be a homeassistant "
+            f"{', '.join(WIZARD_INPUT_DOMAINS)} entity"
+        )
+    if CONF_ENTITY_ID in declaration:
+        # An entity_id in the configuration is a static entry, which is kept apart from the dynamic ones
+        raise cv.Invalid(
+            f"'{conf[CONF_ENTITY].id}' has an entity_id set in its configuration, so it cannot be a "
+            "wizard input. Remove entity_id to let Home Assistant set it through the wizard."
+        )
+    if domain in WIZARD_DOMAIN_LIMITED_PLATFORMS:
+        supported = _wizard_default_domains(domain)
+        for entity_filter in conf.get(CONF_TARGET, {}).get(CONF_ENTITY, []):
+            if not (domains := entity_filter.get(CONF_DOMAIN)):
+                raise cv.Invalid(
+                    f"Every filter of a homeassistant {domain} input must set domain"
+                )
+            if unsupported := [d for d in domains if d not in supported]:
+                raise cv.Invalid(
+                    f"The homeassistant {domain} does not support the domain(s) "
+                    f"{', '.join(unsupported)}. Supported: {', '.join(supported)}"
+                )
+    return conf
+
+
+def _validate_wizard_entity_exposed(value: ID) -> ID:
+    """Reject entities that are internal, as they are not exposed over the API, or have no name.
+
+    The key a client knows an entity by is a hash of its name. Without a name of its own, the
+    device works the name out at runtime from its friendly name, which can add the MAC address,
+    so the key cannot be known when the wizard is built.
+    """
+    _, declaration = _wizard_input_declaration(fv.full_config.get(), value)
+    if declaration.get(CONF_INTERNAL, False):
+        raise cv.Invalid(
+            f"Entity '{value.id}' is internal, so it is not exposed over the API "
+            "and cannot be used in the wizard"
+        )
+    if not declaration.get(CONF_NAME):
+        raise cv.Invalid(
+            f"Entity '{value.id}' has no name of its own, so its key is not known "
+            "when the wizard is built. Give it a name to use it in the wizard"
+        )
+    return value
+
+
+_WIZARD_FINAL_VALIDATE_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_WIZARD): {
+            cv.Optional(CONF_PAGES): [
+                {
+                    cv.Optional(CONF_ENTITIES): [
+                        {cv.Optional(CONF_ID): _validate_wizard_entity_exposed}
+                    ],
+                    cv.Optional(CONF_INPUTS): [_validate_wizard_input],
+                }
+            ]
+        }
+    },
+    extra=cv.ALLOW_EXTRA,
+)
+
+
+def final_validate(config: ConfigType) -> None:
+    """Final validation of the wizard in the given api config, if it has one."""
+    _WIZARD_FINAL_VALIDATE_SCHEMA(config)
+    if (wizard := config.get(CONF_WIZARD)) is not None:
+        size = len(wizard_blob(wizard, fv.full_config.get()))
+        if size > WIZARD_RESPONSE_MAX_SIZE:
+            raise cv.Invalid(
+                f"The compressed wizard is {size} bytes, {size - WIZARD_RESPONSE_MAX_SIZE} "
+                f"bytes over the {WIZARD_RESPONSE_MAX_SIZE} bytes one API message can hold. "
+                "Shorten the texts or use fewer pages, entities or filters",
+                path=[CONF_WIZARD],
+            )
+
+
+WIZARD_INPUT_IS_SET_SCHEMA = cv.maybe_simple_value(
+    {cv.Required(CONF_ID): cv.use_id(WizardInput)}, key=CONF_ID
+)
+
+# Only for standalone inputs: a linked input is read through its homeassistant entity
+automation.register_apply_condition(
+    "api.wizard.input_is_set", WIZARD_INPUT_IS_SET_SCHEMA, "has_entity_id()"
+)
+
+
+def _entity_document(conf: ConfigType, config: fv.FinalValidateConfig) -> ConfigType:
+    """An entity of the device that the page shows, keyed as ListEntitiesResponse keys it."""
+    _, declaration = _wizard_input_declaration(config, conf[CONF_ID])
+    document: ConfigType = {"key": fnv1_hash_object_id(declaration[CONF_NAME])}
+    if (device := declaration.get(CONF_DEVICE_ID)) is not None:
+        document["device_id"] = fnv1a_32bit_hash(device.id)
+    if description := conf.get(CONF_DESCRIPTION):
+        document[CONF_DESCRIPTION] = description
+    return document
+
+
+def _input_document(conf: ConfigType, config: fv.FinalValidateConfig) -> ConfigType:
+    document: ConfigType = {"key": fnv1_hash(_wizard_input_id(conf).id)}
+    if description := conf.get(CONF_DESCRIPTION):
+        document[CONF_DESCRIPTION] = description
+    if conf.get(CONF_MULTIPLE):
+        document["multiple"] = True
+    if (max_length := conf.get(CONF_MAX_LENGTH)) is not None:
+        document["max_length"] = max_length
+    if filters := _wizard_input_filters(conf, config):
+        document["entity_filters"] = [dict(entity_filter) for entity_filter in filters]
+    return document
+
+
+def wizard_document(wizard: ConfigType, config: fv.FinalValidateConfig) -> ConfigType:
+    """The wizard as the JSON document the device sends, before it is serialised.
+
+    This is the format Home Assistant reads, and api.proto documents it for clients. Version 1:
+
+        {"version": 1,
+         "pages": [{"title": "...", "description": "...",
+           "entities": [{"key": 123, "device_id": 456, "description": "..."}],
+           "inputs": [{"key": 789, "description": "...", "multiple": true, "max_length": 1023,
+             "entity_filters": [{"integration": "...", "domain": ["..."],
+                                 "device_class": ["..."], "supported_features": ["..."]}]}]}]}
+
+    Anything empty or unset, and every empty list, is left out. Strings are passed through as
+    written, so they may be Home Assistant translation placeholders.
+
+    - An entity key is the key ListEntitiesResponse sends for the entity: the FNV-1 hash of the
+      object id made from its name (entity_helpers). device_id is the hash of the ESPHome id of
+      the device it belongs to (esphome/core/config.py), and is left out for the main device.
+    - An input key is the FNV-1 hash of the ESPHome id of the input, or of the linked entity. A linked
+      entity must not set entity_id, as that is a static entry kept apart from the ones the wizard sets.
+    - multiple means the user may pick several entities. The client sends them in one
+      WizardInputSetRequest as a comma separated list ("calendar.a,calendar.b") with no spaces; the
+      device trims spaces around each id and stores the list without them. The whole request is
+      ignored when any id is empty or has no '.', or when the list without spaces does not fit
+      max_length (only on a multiple input, 255 when left out). A single input is ignored when the id
+      is empty, longer than 255 bytes or has no '.'. The version stays 1: a client that does not know
+      multiple ignores it, shows a single picker and sends one entity id, which a multiple input
+      accepts.
+    - entity_filters are the filters of the input, or the default filters of a linked switch,
+      number, text, select or button.
+    """
+    pages: list[ConfigType] = []
+    for page in wizard[CONF_PAGES]:
+        document: ConfigType = {}
+        for key in (CONF_TITLE, CONF_DESCRIPTION):
+            if value := page.get(key):
+                document[key] = value
+        if entities := [
+            _entity_document(e, config) for e in page.get(CONF_ENTITIES, [])
+        ]:
+            document[CONF_ENTITIES] = entities
+        if inputs := [_input_document(i, config) for i in page.get(CONF_INPUTS, [])]:
+            document[CONF_INPUTS] = inputs
+        pages.append(document)
+    return {"version": WIZARD_JSON_VERSION, CONF_PAGES: pages}
+
+
+def wizard_blob(wizard: ConfigType, config: fv.FinalValidateConfig) -> bytes:
+    """The wizard document as compact, sorted UTF-8 JSON in a single zstd frame."""
+    text = json.dumps(
+        wizard_document(wizard, config),
+        separators=(",", ":"),
+        sort_keys=True,
+        ensure_ascii=False,
+    )
+    return zstd_module().compress(text.encode("utf-8"), level=WIZARD_ZSTD_LEVEL)
+
+
+async def to_code(wizard: ConfigType) -> None:
+    """Emit the compressed wizard, the table of inputs and the defines.
+
+    The API reads both tables from its own sources, so they are externally linked PROGMEM arrays.
+    """
+    blob = wizard_blob(wizard, CORE.config)
+    cg.extern_progmem_array("esphome::api::API_WIZARD_DATA", cg.uint8, list(blob))
+    cg.add_define("API_WIZARD_DATA_SIZE", len(blob))
+    for define in sorted(_wizard_defines(wizard)):
+        cg.add_define(define)
+    entries: list[cg.RawExpression] = []
+    for conf in _wizard_inputs(wizard):
+        input_id = _wizard_input_id(conf)
+        # Every buffer starts empty, until the wizard sets it. A linked homeassistant entity uses it as its entity id.
+        buffer = _wizard_buffer_name(input_id)
+        size = conf.get(CONF_MAX_LENGTH, WIZARD_ENTITY_ID_MAX_LENGTH) + 1
+        cg.add_global(cg.RawStatement(f'static char {buffer}[{size}] = "";'))
+        if CONF_ID in conf:
+            cg.new_Pvariable(input_id, cg.RawExpression(buffer))
+        key = fnv1_hash(input_id.id)
+        if conf[CONF_MULTIPLE]:
+            entries.append(cg.RawExpression(f"{{{key}u, {buffer}, {size}}}"))
+        else:
+            entries.append(cg.RawExpression(f"{{{key}u, {buffer}}}"))
+    if entries:
+        cg.extern_progmem_array(
+            "esphome::api::API_WIZARD_INPUTS",
+            cg.esphome_ns.namespace("api").struct("WizardInputEntry"),
+            entries,
+        )
+        cg.add_define("API_WIZARD_INPUT_COUNT", len(entries))
@@ -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)
@@ -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)
@@ -6,7 +6,7 @@ import esphome.codegen as cg
 from esphome.components.esp32 import (
    add_idf_component,
    add_idf_sdkconfig_option,
-    include_builtin_idf_component,
+    request_http_client,
    require_certificate_bundle,
 )
 import esphome.config_validation as cv
@@ -334,8 +334,7 @@ def _emit_memory_pair(value: str | None, psram_key: str, internal_key: str) -> N


 async def to_code(config: ConfigType) -> None:
-    # Re-enable ESP-IDF's HTTP client (excluded by default to save compile time)
-    include_builtin_idf_component("esp_http_client")
+    request_http_client()
    # HTTPS streams verify the server against the root certificate bundle
    require_certificate_bundle()

@@ -392,7 +391,7 @@ async def to_code(config: ConfigType) -> None:
    # Adds a define and IDF component for legacy `audio_decoder.cpp`.
    if data.flac_support:
        cg.add_define("USE_AUDIO_FLAC_SUPPORT")
-        add_idf_component(name="esphome/micro-flac", ref="0.2.0")
+        add_idf_component(name="esphome/micro-flac", ref="0.3.0")
        _emit_memory_pair(
            data.flac.buffer_memory,
            "CONFIG_MICRO_FLAC_PREFER_PSRAM",
@@ -72,7 +72,7 @@ esp_err_t AudioReader::add_sink(const std::weak_ptr<ring_buffer::RingBuffer> &ou
  return ESP_ERR_INVALID_STATE;
 }

-esp_err_t AudioReader::start(AudioFile *audio_file, AudioFileType &file_type) {
+esp_err_t AudioReader::start(const AudioFile *audio_file, AudioFileType &file_type) {
  file_type = AudioFileType::NONE;

  this->current_audio_file_ = audio_file;
@@ -47,7 +47,7 @@ class AudioReader {
  /// @param audio_file AudioFile struct containing the file.
  /// @param file_type AudioFileType variable passed-by-reference indicating the type of file being read.
  /// @return ESP_OK
-  esp_err_t start(AudioFile *audio_file, AudioFileType &file_type);
+  esp_err_t start(const AudioFile *audio_file, AudioFileType &file_type);

  /// @brief Reads new file data from the source and sends to the ring buffer sink.
  /// @return AudioReaderState
@@ -69,7 +69,7 @@ class AudioReader {

  esp_http_client_handle_t client_{nullptr};

-  AudioFile *current_audio_file_{nullptr};
+  const AudioFile *current_audio_file_{nullptr};
  AudioFileType audio_file_type_{AudioFileType::NONE};
  const uint8_t *file_current_{nullptr};
 };
@@ -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};
 };
@@ -19,7 +19,7 @@ from esphome.const import (
    CONF_URL,
 )
 from esphome.core import CORE, ID, HexInt
-from esphome.cpp_generator import MockObj
+from esphome.cpp_generator import MockObj, ProgmemAssignmentExpression
 from esphome.external_files import download_web_files_in_config
 from esphome.types import ConfigType

@@ -151,11 +151,14 @@ TYPED_FILE_SCHEMA = cv.typed_schema(
 )


+CONF_FILE_DATA_ID = "file_data_id"
+
 MEDIA_FILE_TYPE_SCHEMA = cv.Schema(
    {
        cv.Required(CONF_ID): cv.declare_id(audio.AudioFile),
        cv.Required(CONF_FILE): _file_schema,
        cv.GenerateID(CONF_RAW_DATA_ID): cv.declare_id(cg.uint8),
+        cv.GenerateID(CONF_FILE_DATA_ID): cv.declare_id(audio.AudioFile),
    }
 )

@@ -217,9 +220,9 @@ def audio_files_schema() -> cv.All:


 def generate_audio_file_code(file_config: ConfigType) -> MockObj:
-    """Generate the progmem data, AudioFile struct, and Pvariable for one file.
+    """Generate the progmem data and a flash AudioFile for one file.

-    Returns the created Pvariable. Caller is responsible for any further
+    Returns a const pointer to the AudioFile. Caller is responsible for any further
    registration (the audio_file component additionally registers each file in
    its named C++ registry; other consumers may skip that).
    """
@@ -230,17 +233,33 @@ def generate_audio_file_code(file_config: ConfigType) -> MockObj:
    else:
        data, media_file_type = read_audio_file_and_type(file_config)

-    rhs = [HexInt(x) for x in data]
-    prog_arr = cg.progmem_array(file_config[CONF_RAW_DATA_ID], rhs)
-
-    media_files_struct = cg.StructInitializer(
+    # Global constants so the AudioFile lives in flash; the id stays a plain pointer
+    # because actions render id arguments as ``::<id>``.
+    data_id = file_config[CONF_RAW_DATA_ID]
+    cg.add_global(
+        ProgmemAssignmentExpression(
+            data_id.type, data_id, cg.safe_exp([HexInt(x) for x in data])
+        )
+    )
+    media_file = cg.StructInitializer(
        audio.AudioFile,
-        ("data", prog_arr),
-        ("length", len(rhs)),
+        ("data", MockObj(data_id, ".")),
+        ("length", len(data)),
        ("file_type", media_file_type),
    )
-
-    return cg.new_Pvariable(file_config[CONF_ID], media_files_struct)
+    file_var_id = file_config[CONF_ID]
+    storage = file_config[CONF_FILE_DATA_ID]
+    cg.add_global(
+        cg.RawStatement(f"static constexpr {storage.type} {storage} = {media_file};")
+    )
+    cg.add_global(
+        cg.RawStatement(
+            f"static const {storage.type} *const {file_var_id} = &{storage};"
+        )
+    )
+    var = MockObj(file_var_id, "->")
+    CORE.register_variable(file_var_id, var)
+    return var


 CONFIG_SCHEMA = cv.All(
@@ -10,14 +10,14 @@
 namespace esphome::audio_file {

 struct NamedAudioFile {
-  audio::AudioFile *file;
+  const audio::AudioFile *file;
  const char *file_id;
 };

 inline StaticVector<NamedAudioFile, AUDIO_FILE_MAX_FILES>
    named_audio_files;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)

-inline void add_named_audio_file(audio::AudioFile *file, const char *file_id) {
+inline void add_named_audio_file(const audio::AudioFile *file, const char *file_id) {
  named_audio_files.push_back({file, file_id});
 }

@@ -46,7 +46,7 @@ class AudioFileMediaSource final : public Component,
 protected:
  std::unique_ptr<micro_decoder::DecoderSource> decoder_;
  audio::AudioStreamInfo stream_info_;
-  audio::AudioFile *current_file_{nullptr};
+  const audio::AudioFile *current_file_{nullptr};

  // Written from the main loop in handle_command(), read from the decoder task in
  // on_audio_write(). Must be atomic to avoid a data race.
@@ -33,6 +33,9 @@ void AudioHTTPMediaSource::dump_config() {
                "  Persistent Ring Buffer: %s\n"
                "  Decoder Task Stack in PSRAM: %s",
                this->buffer_size_, YESNO(this->persistent_ring_buffer_), YESNO(this->decoder_task_stack_in_psram_));
+#ifdef USE_AUDIO_HTTP_CA_CERTIFICATE
+  ESP_LOGCONFIG(TAG, "  Custom CA Certificate: %s", YESNO(this->http_ca_certificate_ != nullptr));
+#endif
 }

 void AudioHTTPMediaSource::setup() {
@@ -52,6 +55,12 @@ void AudioHTTPMediaSource::setup() {
  config.reader_stack_size = READER_TASK_STACK_SIZE;
  config.decoder_stack_size = DECODER_TASK_STACK_SIZE;
  config.decoder_stack_in_psram = this->decoder_task_stack_in_psram_;
+#ifdef USE_AUDIO_HTTP_CA_CERTIFICATE
+  // micro-decoder verifies HTTPS against this PEM only, skipping the built-in certificate bundle.
+  if (this->http_ca_certificate_ != nullptr) {
+    config.http_ca_certificate = this->http_ca_certificate_;
+  }
+#endif

  this->decoder_ = std::make_unique<micro_decoder::DecoderSource>(config);
  if (this->decoder_ == nullptr) {
@@ -34,6 +34,11 @@ class AudioHTTPMediaSource final : public Component,
  void set_buffer_size(size_t buffer_size) { this->buffer_size_ = buffer_size; }
  void set_task_stack_in_psram(bool task_stack_in_psram) { this->decoder_task_stack_in_psram_ = task_stack_in_psram; }
  void set_persistent_ring_buffer(bool persistent) { this->persistent_ring_buffer_ = persistent; }
+#ifdef USE_AUDIO_HTTP_CA_CERTIFICATE
+  /// PEM-encoded CA certificate(s) used as the sole trust anchor for HTTPS playback URLs,
+  /// replacing the built-in certificate bundle.
+  void set_http_ca_certificate(const char *ca_certificate) { this->http_ca_certificate_ = ca_certificate; }
+#endif

  // MediaSource interface implementation
  bool play_uri(const std::string &uri) override;
@@ -56,6 +61,9 @@ class AudioHTTPMediaSource final : public Component,
  std::atomic<bool> pause_{false};
  bool decoder_task_stack_in_psram_{false};
  bool persistent_ring_buffer_{false};
+#ifdef USE_AUDIO_HTTP_CA_CERTIFICATE
+  const char *http_ca_certificate_{nullptr};
+#endif
 };

 }  // namespace esphome::audio_http
@@ -1,13 +1,22 @@
+import logging
+from pathlib import Path
+
 import esphome.codegen as cg
 from esphome.components import audio, media_source, psram
 import esphome.config_validation as cv
 from esphome.const import CONF_BUFFER_SIZE, CONF_ID, CONF_TASK_STACK_IN_PSRAM
+import esphome.final_validate as fv
 from esphome.types import ConfigType

+_LOGGER = logging.getLogger(__name__)
+
 CODEOWNERS = ["@kahrendt"]
 AUTO_LOAD = ["audio"]

 CONF_PERSISTENT_RING_BUFFER = "persistent_ring_buffer"
+CONF_CA_CERTIFICATE_PATH = "ca_certificate_path"
+CONF_HTTP_REQUEST = "http_request"
+CONF_VERIFY_SSL = "verify_ssl"

 audio_http_ns = cg.esphome_ns.namespace("audio_http")
 AudioHTTPMediaSource = audio_http_ns.class_(
@@ -20,6 +29,38 @@ def _request_micro_decoder(config: ConfigType) -> ConfigType:
    return config


+def _inherit_ca_certificate_path(config: ConfigType) -> ConfigType:
+    # Default to the CA certificate configured on the http_request component so
+    # HTTPS playback verifies against the same trust anchor without repeating
+    # the option on every source. Needed because audio_http sources are often
+    # declared by device packages and cannot be extended from the device config.
+    # The PEM replaces the built-in certificate bundle as the sole trust anchor,
+    # so make the inheritance visible in the log.
+    if CONF_CA_CERTIFICATE_PATH in config:
+        return config
+    fconf = fv.full_config.get()
+    if CONF_HTTP_REQUEST not in fconf:
+        return config
+    http_request_config = fconf[CONF_HTTP_REQUEST]
+    # Mirror http_request's own semantics: it only applies its CA when SSL
+    # verification is enabled, so neither does the inheritance.
+    if not http_request_config.get(CONF_VERIFY_SSL, True):
+        return config
+    if ca_cert_path := http_request_config.get(CONF_CA_CERTIFICATE_PATH):
+        _LOGGER.info(
+            "audio_http source '%s' is inheriting ca_certificate_path from the "
+            "http_request component; HTTPS playback will verify against that PEM "
+            "instead of the built-in certificate bundle",
+            config[CONF_ID].id,
+        )
+        # Already validated by http_request's schema; the value is a resolved Path.
+        config[CONF_CA_CERTIFICATE_PATH] = ca_cert_path
+    return config
+
+
+FINAL_VALIDATE_SCHEMA = _inherit_ca_certificate_path
+
+
 CONFIG_SCHEMA = cv.All(
    media_source.media_source_schema(
        AudioHTTPMediaSource,
@@ -31,6 +72,7 @@ CONFIG_SCHEMA = cv.All(
            ),
            cv.Optional(CONF_TASK_STACK_IN_PSRAM): psram.validate_task_stack_in_psram,
            cv.Optional(CONF_PERSISTENT_RING_BUFFER, default=False): cv.boolean,
+            cv.Optional(CONF_CA_CERTIFICATE_PATH): cv.file_,
        }
    )
    .extend(cv.COMPONENT_SCHEMA),
@@ -47,5 +89,16 @@ async def to_code(config: ConfigType) -> None:
    if config.get(CONF_TASK_STACK_IN_PSRAM):
        cg.add(var.set_task_stack_in_psram(True))
        psram.request_external_task_stack()
+
    cg.add(var.set_buffer_size(config[CONF_BUFFER_SIZE]))
    cg.add(var.set_persistent_ring_buffer(config[CONF_PERSISTENT_RING_BUFFER]))
+
+    # Embed the certificate content, like http_request does. Passed to
+    # micro_decoder's DecoderConfig::http_ca_certificate, which then uses it as
+    # the sole trust anchor for HTTPS playback URLs instead of the certificate
+    # bundle.
+    if ca_cert_path := config.get(CONF_CA_CERTIFICATE_PATH):
+        cg.add_define("USE_AUDIO_HTTP_CA_CERTIFICATE")
+        with Path(ca_cert_path).open(encoding="utf-8") as f:
+            ca_cert_content = f.read()
+        cg.add(var.set_http_ca_certificate(ca_cert_content))
@@ -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)
@@ -11,29 +11,34 @@
 #include "esphome/core/automation.h"
 #include "esphome/core/helpers.h"

-#include <algorithm>
-#include <initializer_list>
-
 namespace esphome::ble_device_base {

+/// True if `address` is in `table`, a list of MACs ended by 0.
+inline bool mac_in_table(const uint64_t *table, uint64_t address) {
+  for (; *table != 0; table++) {
+    if (*table == address)
+      return true;
+  }
+  return false;
+}
+
 // on_ble_advertise: fires on every BLE advertisement, optionally filtered to one or more MACs.
 class ESPBTAdvertiseTrigger final : public Trigger<const ESPBTDevice &>, public ESPBTDeviceListener {
 public:
  template<typename Hub> explicit ESPBTAdvertiseTrigger(Hub *parent) { parent->register_listener(this); }

-  void set_addresses(std::initializer_list<uint64_t> addresses) { this->addresses_ = addresses; }
+  /// Table of MACs ended by 0; must outlive the trigger.
+  void set_addresses(const uint64_t *addresses) { this->addresses_ = addresses; }

  bool parse_device(const ESPBTDevice &device) override {
-    if (!this->addresses_.empty() && std::find(this->addresses_.begin(), this->addresses_.end(),
-                                               device.address_uint64()) == this->addresses_.end()) {
+    if (this->addresses_ != nullptr && !mac_in_table(this->addresses_, device.address_uint64()))
      return false;
-    }
    this->trigger(device);
    return true;
  }

 protected:
-  FixedVector<uint64_t> addresses_;
+  const uint64_t *addresses_{nullptr};
 };

 // on_ble_service_data_advertise: fires when an advertisement contains service
@@ -69,13 +69,24 @@ def uuid_trigger_schema(
    )


+def _filter_mac(value: Any) -> Any:
+    mac = cv.mac_address(value)
+    if not any(mac.parts):
+        # 0 ends the flash MAC table, and it is never a real device address.
+        raise cv.Invalid("00:00:00:00:00:00 cannot be used as a MAC address filter")
+    return mac
+
+
+MAC_FILTER_LIST = cv.ensure_list(_filter_mac)
+
+
 def advertise_trigger_schema(trigger_class: MockObjClass) -> Callable[[Any], Any]:
    """on_ble_advertise schema: multi-mac list filter, unlike the single-mac
    uuid_trigger_schema() — pairs with advertise_trigger_to_code()."""
    return automation.validate_automation(
        {
            cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(trigger_class),
-            cv.Optional(CONF_MAC_ADDRESS): cv.ensure_list(cv.mac_address),
+            cv.Optional(CONF_MAC_ADDRESS): MAC_FILTER_LIST,
        }
    )

@@ -94,11 +105,18 @@ def scan_end_trigger_schema(trigger_class: MockObjClass) -> Callable[[Any], Any]
 _count_listener = cg.slot_counter(LISTENER_COUNT_DEFINE)


+def mac_filter_table(macs: list) -> cg.MockObj:
+    """Shared flash table of MACs ended by 0 (never a valid address), so triggers store a pointer."""
+    return cg.shared_progmem_array(
+        "ble_mac_filter", cg.uint64, [*(mac.as_hex for mac in macs), 0]
+    )
+
+
 async def advertise_trigger_to_code(conf: ConfigType, var: cg.MockObj) -> None:
    """Build an on_ble_advertise trigger (optional multi-mac filter)."""
    trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
-    if (macs := conf.get(CONF_MAC_ADDRESS)) is not None:
-        cg.add(trigger.set_addresses([it.as_hex for it in macs]))
+    if macs := conf.get(CONF_MAC_ADDRESS):
+        cg.add(trigger.set_addresses(mac_filter_table(macs)))
    await automation.build_automation(trigger, [(ESPBTDeviceConstRef, "x")], conf)
    _count_listener()

@@ -62,6 +62,7 @@ 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))
@@ -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");
@@ -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;
    }
@@ -19,6 +19,9 @@ CONF_REMOTE_TRANSMISSION_REQUEST = "remote_transmission_request"
 CONF_CANBUS_ID = "canbus_id"
 CONF_BIT_RATE = "bit_rate"
 CONF_ON_FRAME = "on_frame"
+CONF_MAX_FRAMES_PER_LOOP = "max_frames_per_loop"
+DEFAULT_MAX_FRAMES_PER_LOOP = 50  # Keep in sync with max_frames_per_loop_ in canbus.h
+DEFAULT_BIT_RATE = "125KBPS"  # Keep in sync with bit_rate_ in canbus.h


 def validate_id(config: ConfigType) -> ConfigType:
@@ -86,8 +89,13 @@ CANBUS_SCHEMA = cv.Schema(
    {
        cv.GenerateID(): cv.declare_id(CanbusComponent),
        cv.Required(CONF_CAN_ID): cv.int_range(min=0, max=0x1FFFFFFF),
-        cv.Optional(CONF_BIT_RATE, default="125KBPS"): cv.enum(CAN_SPEEDS, upper=True),
+        cv.Optional(CONF_BIT_RATE, default=DEFAULT_BIT_RATE): cv.enum(
+            CAN_SPEEDS, upper=True
+        ),
        cv.Optional(CONF_USE_EXTENDED_ID, default=False): cv.boolean,
+        cv.Optional(
+            CONF_MAX_FRAMES_PER_LOOP, default=DEFAULT_MAX_FRAMES_PER_LOOP
+        ): cv.positive_not_null_int,
        cv.Optional(CONF_ON_FRAME): automation.validate_automation(
            {
                cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(CanbusTrigger),
@@ -108,9 +116,13 @@ CANBUS_SCHEMA.add_extra(validate_id)

 async def setup_canbus_core_(var: MockObj, config: ConfigType) -> None:
    await cg.register_component(var, config)
-    cg.add(var.set_can_id([config[CONF_CAN_ID]]))
-    cg.add(var.set_use_extended_id([config[CONF_USE_EXTENDED_ID]]))
-    cg.add(var.set_bitrate(CAN_SPEEDS[config[CONF_BIT_RATE]]))
+    cg.add(var.set_can_id(config[CONF_CAN_ID]))
+    if config[CONF_USE_EXTENDED_ID]:
+        cg.add(var.set_use_extended_id(True))
+    if (bit_rate := config[CONF_BIT_RATE]) != DEFAULT_BIT_RATE:
+        cg.add(var.set_bitrate(CAN_SPEEDS[bit_rate]))
+    if (max_frames := config[CONF_MAX_FRAMES_PER_LOOP]) != DEFAULT_MAX_FRAMES_PER_LOOP:
+        cg.add(var.set_max_frames_per_loop(max_frames))

    for conf in config.get(CONF_ON_FRAME, []):
        can_id = conf[CONF_CAN_ID]
@@ -67,16 +67,18 @@ void Canbus::add_trigger(CanbusTrigger *trigger) {

 void Canbus::loop() {
  struct CanFrame can_message;
-  // read all messages until queue is empty
-  int message_counter = 0;
-  while (this->read_message(&can_message) == canbus::ERROR_OK) {
-    message_counter++;
+  uint32_t message_counter = 0;
+  for (; message_counter < this->max_frames_per_loop_; message_counter++) {
+    if (this->read_message(&can_message) != canbus::ERROR_OK) {
+      break;
+    }
+
    if (can_message.use_extended_id) {
-      ESP_LOGD(TAG, "received can message (#%d) extended can_id=0x%" PRIx32 " size=%d", message_counter,
+      ESP_LOGD(TAG, "received can message (#%" PRIu32 ") extended can_id=0x%" PRIx32 " size=%d", message_counter + 1,
               can_message.can_id, can_message.can_data_length_code);
    } else {
-      ESP_LOGD(TAG, "received can message (#%d) std can_id=0x%" PRIx32 " size=%d", message_counter, can_message.can_id,
-               can_message.can_data_length_code);
+      ESP_LOGD(TAG, "received can message (#%" PRIu32 ") std can_id=0x%" PRIx32 " size=%d", message_counter + 1,
+               can_message.can_id, can_message.can_data_length_code);
    }

    std::vector<uint8_t> data;
@@ -100,6 +102,12 @@ void Canbus::loop() {
      }
    }
  }
+
+  if (message_counter == this->max_frames_per_loop_) {
+    ESP_LOGW(TAG,
+             "Reached max_frames_per_loop=%" PRIu32 ", deferring remaining CAN frames. Some frames might be dropped",
+             this->max_frames_per_loop_);
+  }
 }

 }  // namespace esphome::canbus
@@ -78,6 +78,7 @@ class Canbus : public Component {
  void set_can_id(uint32_t can_id) { this->can_id_ = can_id; }
  void set_use_extended_id(bool use_extended_id) { this->use_extended_id_ = use_extended_id; }
  void set_bitrate(CanSpeed bit_rate) { this->bit_rate_ = bit_rate; }
+  void set_max_frames_per_loop(uint32_t max_frames_per_loop) { this->max_frames_per_loop_ = max_frames_per_loop; }

  void add_trigger(CanbusTrigger *trigger);
  /**
@@ -96,8 +97,9 @@ class Canbus : public Component {
  template<typename... Ts> friend class CanbusSendAction;
  std::vector<CanbusTrigger *> triggers_{};
  uint32_t can_id_;
-  bool use_extended_id_;
-  CanSpeed bit_rate_;
+  uint32_t max_frames_per_loop_{50};  // Keep in sync with DEFAULT_MAX_FRAMES_PER_LOOP in __init__.py
+  CanSpeed bit_rate_{CAN_125KBPS};    // Keep in sync with DEFAULT_BIT_RATE in __init__.py
+  bool use_extended_id_{false};
  CallbackManager<void(uint32_t can_id, bool extended_id, bool rtr, const std::vector<uint8_t> &data)>
      callback_manager_{};

@@ -253,11 +253,17 @@ void CC1101Component::dump_config() {
 }

 void CC1101Component::begin_tx() {
+  // Read the mode before the PKTCTRL0 write below overwrites it in state_
+  const bool packet_mode = this->state_.PKT_FORMAT == static_cast<uint8_t>(PacketFormat::PACKET_FORMAT_FIFO);
  // Ensure Packet Format is 3 (Async Serial)
  this->write_(Register::PKTCTRL0, 0x32);
  ESP_LOGV(TAG, "Beginning TX sequence");
  if (this->gdo0_pin_ != nullptr) {
-    this->gdo0_pin_->detach_interrupt();
+    // setup() only attaches the interrupt in packet mode. In async serial mode the pin may be
+    // shared with remote_receiver, and detaching here would remove the receiver's interrupt.
+    if (packet_mode) {
+      this->gdo0_pin_->detach_interrupt();
+    }
    this->gdo0_pin_->pin_mode(gpio::FLAG_OUTPUT);
  }
  // Transition through IDLE to bypass CCA (Clear Channel Assessment) which can
@@ -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(
@@ -1,5 +1,3 @@
-import logging
-
 import esphome.codegen as cg
 from esphome.components import sensor
 import esphome.config_validation as cv
@@ -18,8 +16,6 @@ from esphome.const import (
 from esphome.core.entity_helpers import inherit_property_from
 from esphome.types import ConfigType

-_LOGGER = logging.getLogger(__name__)
-
 CODEOWNERS = ["@Cat-Ion", "@kahrendt"]

 combination_ns = cg.esphome_ns.namespace("combination")
@@ -75,33 +71,19 @@ KALMAN_SOURCE_SCHEMA = cv.Schema(
 )


-def _migrate_coeffecient(config: ConfigType) -> ConfigType:
-    """Migrate deprecated 'coeffecient' spelling to 'coefficient'."""
-    if CONF_COEFFECIENT in config:
-        if CONF_COEFFICIENT in config:
-            raise cv.Invalid(
-                f"Cannot specify both '{CONF_COEFFICIENT}' and '{CONF_COEFFECIENT}'"
-            )
-        _LOGGER.warning(
-            "'%s' is deprecated, use '%s' instead. Will be removed in 2026.12.0",
-            CONF_COEFFECIENT,
-            CONF_COEFFICIENT,
-        )
-        config[CONF_COEFFICIENT] = config.pop(CONF_COEFFECIENT)
-    elif CONF_COEFFICIENT not in config:
-        raise cv.Invalid(f"'{CONF_COEFFICIENT}' is a required option")
-    return config
-
-
 LINEAR_SOURCE_SCHEMA = cv.All(
+    cv.rename_key(
+        CONF_COEFFECIENT,
+        CONF_COEFFICIENT,
+        removed_in="2026.12.0",
+        component="combination",
+    ),
    cv.Schema(
        {
            cv.Required(CONF_SOURCE): cv.use_id(sensor.Sensor),
-            cv.Optional(CONF_COEFFICIENT): cv.templatable(cv.float_),
-            cv.Optional(CONF_COEFFECIENT): cv.templatable(cv.float_),
+            cv.Required(CONF_COEFFICIENT): cv.templatable(cv.float_),
        }
    ),
-    _migrate_coeffecient,
 )

 SENSOR_ONLY_SOURCE_SCHEMA = cv.Schema(
@@ -203,6 +185,5 @@ 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 +16,7 @@ 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"
@@ -41,7 +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"
@@ -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(
--- a/Show More
+++ b/Show More