Merge branch 'dev' into ota_handle_data_cleanups

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.clang-tidy.hash

@@ -1 +1 @@
-d7693a1e996cacd4a3d1c9a16336799c2a8cc3db02e4e74084151ce964581248
+3d46b63015d761c85ca9cb77ab79a389509e5776701fb22aed16e7b79d432c0c

.github/workflows/auto-label-pr.yml

@@ -53,6 +53,7 @@ jobs:
               'new-target-platform',
               'merging-to-release',
               'merging-to-beta',
+              'chained-pr',
               'core',
               'small-pr',
               'dashboard',
@@ -140,6 +141,8 @@ jobs:
                 labels.add('merging-to-release');
               } else if (baseRef === 'beta') {
                 labels.add('merging-to-beta');
+              } else if (baseRef !== 'dev') {
+                labels.add('chained-pr');
               }
 
               return labels;
@@ -413,7 +416,7 @@ jobs:
             }
 
             // Generate review messages
-            function generateReviewMessages(finalLabels) {
+            function generateReviewMessages(finalLabels, originalLabelCount) {
               const messages = [];
               const prAuthor = context.payload.pull_request.user.login;
 
@@ -427,15 +430,15 @@ jobs:
                   .reduce((sum, file) => sum + (file.deletions || 0), 0);
                 const nonTestChanges = (totalAdditions - testAdditions) - (totalDeletions - testDeletions);
 
-                const tooManyLabels = finalLabels.length > MAX_LABELS;
+                const tooManyLabels = originalLabelCount > MAX_LABELS;
                 const tooManyChanges = nonTestChanges > TOO_BIG_THRESHOLD;
 
                 let message = `${TOO_BIG_MARKER}\n### 📦 Pull Request Size\n\n`;
 
                 if (tooManyLabels && tooManyChanges) {
-                  message += `This PR is too large with ${nonTestChanges} line changes (excluding tests) and affects ${finalLabels.length} different components/areas.`;
+                  message += `This PR is too large with ${nonTestChanges} line changes (excluding tests) and affects ${originalLabelCount} different components/areas.`;
                 } else if (tooManyLabels) {
-                  message += `This PR affects ${finalLabels.length} different components/areas.`;
+                  message += `This PR affects ${originalLabelCount} different components/areas.`;
                 } else {
                   message += `This PR is too large with ${nonTestChanges} line changes (excluding tests).`;
                 }
@@ -463,8 +466,8 @@ jobs:
             }
 
             // Handle reviews
-            async function handleReviews(finalLabels) {
-              const reviewMessages = generateReviewMessages(finalLabels);
+            async function handleReviews(finalLabels, originalLabelCount) {
+              const reviewMessages = generateReviewMessages(finalLabels, originalLabelCount);
               const hasReviewableLabels = finalLabels.some(label =>
                 ['too-big', 'needs-codeowners'].includes(label)
               );
@@ -528,8 +531,8 @@ jobs:
             const apiData = await fetchApiData();
             const baseRef = context.payload.pull_request.base.ref;
 
-            // Early exit for non-dev branches
-            if (baseRef !== 'dev') {
+            // Early exit for release and beta branches only
+            if (baseRef === 'release' || baseRef === 'beta') {
               const branchLabels = await detectMergeBranch();
               const finalLabels = Array.from(branchLabels);
 
@@ -624,6 +627,7 @@ jobs:
 
             // Handle too many labels (only for non-mega PRs)
             const tooManyLabels = finalLabels.length > MAX_LABELS;
+            const originalLabelCount = finalLabels.length;
 
             if (tooManyLabels && !isMegaPR && !finalLabels.includes('too-big')) {
               finalLabels = ['too-big'];
@@ -632,7 +636,7 @@ jobs:
             console.log('Computed labels:', finalLabels.join(', '));
 
             // Handle reviews
-            await handleReviews(finalLabels);
+            await handleReviews(finalLabels, originalLabelCount);
 
             // Apply labels
             if (finalLabels.length > 0) {

.github/workflows/ci.yml

@@ -114,7 +114,7 @@ jobs:
       matrix:
         python-version:
           - "3.11"
-          - "3.14"
+          - "3.13"
         os:
           - ubuntu-latest
           - macOS-latest
@@ -123,9 +123,9 @@ jobs:
           # Minimize CI resource usage
           # by only running the Python version
           # version used for docker images on Windows and macOS
-          - python-version: "3.14"
+          - python-version: "3.13"
             os: windows-latest
-          - python-version: "3.14"
+          - python-version: "3.13"
             os: macOS-latest
     runs-on: ${{ matrix.os }}
     needs:
@@ -178,6 +178,8 @@ jobs:
       component-test-count: ${{ steps.determine.outputs.component-test-count }}
       changed-cpp-file-count: ${{ steps.determine.outputs.changed-cpp-file-count }}
       memory_impact: ${{ steps.determine.outputs.memory-impact }}
+      cpp-unit-tests-run-all: ${{ steps.determine.outputs.cpp-unit-tests-run-all }}
+      cpp-unit-tests-components: ${{ steps.determine.outputs.cpp-unit-tests-components }}
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -210,6 +212,8 @@ jobs:
           echo "component-test-count=$(echo "$output" | jq -r '.component_test_count')" >> $GITHUB_OUTPUT
           echo "changed-cpp-file-count=$(echo "$output" | jq -r '.changed_cpp_file_count')" >> $GITHUB_OUTPUT
           echo "memory-impact=$(echo "$output" | jq -c '.memory_impact')" >> $GITHUB_OUTPUT
+          echo "cpp-unit-tests-run-all=$(echo "$output" | jq -r '.cpp_unit_tests_run_all')" >> $GITHUB_OUTPUT
+          echo "cpp-unit-tests-components=$(echo "$output" | jq -c '.cpp_unit_tests_components')" >> $GITHUB_OUTPUT
 
   integration-tests:
     name: Run integration tests
@@ -247,6 +251,33 @@ jobs:
           . venv/bin/activate
           pytest -vv --no-cov --tb=native -n auto tests/integration/
 
+  cpp-unit-tests:
+    name: Run C++ unit tests
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: github.event_name == 'pull_request' && (needs.determine-jobs.outputs.cpp-unit-tests-run-all == 'true' || needs.determine-jobs.outputs.cpp-unit-tests-components != '[]')
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+
+      - name: Run cpp_unit_test.py
+        run: |
+          . venv/bin/activate
+          if [ "${{ needs.determine-jobs.outputs.cpp-unit-tests-run-all }}" = "true" ]; then
+            script/cpp_unit_test.py --all
+          else
+            ARGS=$(echo '${{ needs.determine-jobs.outputs.cpp-unit-tests-components }}' | jq -r '.[] | @sh' | xargs)
+            script/cpp_unit_test.py $ARGS
+          fi
+
   clang-tidy-single:
     name: ${{ matrix.name }}
     runs-on: ubuntu-24.04

.github/workflows/status-check-labels.yml

@@ -14,6 +14,7 @@ jobs:
         label:
           - needs-docs
           - merge-after-release
+          - chained-pr
     steps:
       - name: Check for ${{ matrix.label }} label
         uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0

CODEOWNERS

@@ -201,6 +201,7 @@ esphome/components/havells_solar/* @sourabhjaiswal
 esphome/components/hbridge/fan/* @WeekendWarrior
 esphome/components/hbridge/light/* @DotNetDann
 esphome/components/hbridge/switch/* @dwmw2
+esphome/components/hdc2010/* @optimusprimespace @ssieb
 esphome/components/he60r/* @clydebarrow
 esphome/components/heatpumpir/* @rob-deutsch
 esphome/components/hitachi_ac424/* @sourabhjaiswal

esphome/analyze_memory/cli.py

@@ -231,9 +231,22 @@ class MemoryAnalyzerCLI(MemoryAnalyzer):
                 api_component = (name, mem)
                 break
 
-        # Combine all components to analyze: top ESPHome + all external + API if not already included
-        components_to_analyze = list(top_esphome_components) + list(
-            top_external_components
+        # Also include wifi_stack and other important system components if they exist
+        system_components_to_include = [
+            # Empty list - we've finished debugging symbol categorization
+            # Add component names here if you need to debug their symbols
+        ]
+        system_components = [
+            (name, mem)
+            for name, mem in components
+            if name in system_components_to_include
+        ]
+
+        # Combine all components to analyze: top ESPHome + all external + API if not already included + system components
+        components_to_analyze = (
+            list(top_esphome_components)
+            + list(top_external_components)
+            + system_components
         )
         if api_component and api_component not in components_to_analyze:
             components_to_analyze.append(api_component)

esphome/analyze_memory/const.py

@@ -127,40 +127,39 @@ SYMBOL_PATTERNS = {
         "tryget_socket_unconn",
         "cs_create_ctrl_sock",
         "netbuf_alloc",
+        "tcp_",  # TCP protocol functions
+        "udp_",  # UDP protocol functions
+        "lwip_",  # LwIP stack functions
+        "eagle_lwip",  # ESP-specific LwIP functions
+        "new_linkoutput",  # Link output function
+        "acd_",  # Address Conflict Detection (ACD)
+        "eth_",  # Ethernet functions
+        "mac_enable_bb",  # MAC baseband enable
+        "reassemble_and_dispatch",  # Packet reassembly
     ],
+    # dhcp must come before libc to avoid "dhcp_select" matching "select" pattern
+    "dhcp": ["dhcp", "handle_dhcp"],
     "ipv6_stack": ["nd6_", "ip6_", "mld6_", "icmp6_", "icmp6_input"],
-    "wifi_stack": [
-        "ieee80211",
-        "hostap",
-        "sta_",
-        "ap_",
-        "scan_",
-        "wifi_",
-        "wpa_",
-        "wps_",
-        "esp_wifi",
-        "cnx_",
-        "wpa3_",
-        "sae_",
-        "wDev_",
-        "ic_",
-        "mac_",
-        "esf_buf",
-        "gWpaSm",
-        "sm_WPA",
-        "eapol_",
-        "owe_",
-        "wifiLowLevelInit",
-        "s_do_mapping",
-        "gScanStruct",
-        "ppSearchTxframe",
-        "ppMapWaitTxq",
-        "ppFillAMPDUBar",
-        "ppCheckTxConnTrafficIdle",
-        "ppCalTkipMic",
+    # Order matters! More specific categories must come before general ones.
+    # mdns must come before bluetooth to avoid "_mdns_disable_pcb" matching "ble_" pattern
+    "mdns_lib": ["mdns"],
+    # memory_mgmt must come before wifi_stack to catch mmu_hal_* symbols
+    "memory_mgmt": [
+        "mem_",
+        "memory_",
+        "tlsf_",
+        "memp_",
+        "pbuf_",
+        "pbuf_alloc",
+        "pbuf_copy_partial_pbuf",
+        "esp_mmu_map",
+        "mmu_hal_",
+        "s_do_mapping",  # Memory mapping function, not WiFi
+        "hash_map_",  # Hash map data structure
+        "umm_assimilate",  # UMM malloc assimilation
     ],
-    "bluetooth": ["bt_", "ble_", "l2c_", "gatt_", "gap_", "hci_", "BT_init"],
-    "wifi_bt_coex": ["coex"],
+    # Bluetooth categories must come BEFORE wifi_stack to avoid misclassification
+    # Many BLE symbols contain patterns like "ble_" that would otherwise match wifi patterns
     "bluetooth_rom": ["r_ble", "r_lld", "r_llc", "r_llm"],
     "bluedroid_bt": [
         "bluedroid",
@@ -207,6 +206,61 @@ SYMBOL_PATTERNS = {
         "copy_extra_byte_in_db",
         "parse_read_local_supported_commands_response",
     ],
+    "bluetooth": [
+        "bt_",
+        "_ble_",  # More specific than "ble_" to avoid matching "able_", "enable_", "disable_"
+        "l2c_",
+        "l2ble_",  # L2CAP for BLE
+        "gatt_",
+        "gap_",
+        "hci_",
+        "btsnd_hcic_",  # Bluetooth HCI command send functions
+        "BT_init",
+        "BT_tx_",  # Bluetooth transmit functions
+        "esp_ble_",  # Catch esp_ble_* functions
+    ],
+    "bluetooth_ll": [
+        "llm_",  # Link layer manager
+        "llc_",  # Link layer control
+        "lld_",  # Link layer driver
+        "ld_acl_",  # Link layer ACL (Asynchronous Connection-Oriented)
+        "llcp_",  # Link layer control protocol
+        "lmp_",  # Link manager protocol
+    ],
+    "wifi_bt_coex": ["coex"],
+    "wifi_stack": [
+        "ieee80211",
+        "hostap",
+        "sta_",
+        "wifi_ap_",  # More specific than "ap_" to avoid matching "cap_", "map_"
+        "wifi_scan_",  # More specific than "scan_" to avoid matching "_scan_" in other contexts
+        "wifi_",
+        "wpa_",
+        "wps_",
+        "esp_wifi",
+        "cnx_",
+        "wpa3_",
+        "sae_",
+        "wDev_",
+        "ic_mac_",  # More specific than "mac_" to avoid matching emac_
+        "esf_buf",
+        "gWpaSm",
+        "sm_WPA",
+        "eapol_",
+        "owe_",
+        "wifiLowLevelInit",
+        # Removed "s_do_mapping" - this is memory management, not WiFi
+        "gScanStruct",
+        "ppSearchTxframe",
+        "ppMapWaitTxq",
+        "ppFillAMPDUBar",
+        "ppCheckTxConnTrafficIdle",
+        "ppCalTkipMic",
+        "phy_force_wifi",
+        "phy_unforce_wifi",
+        "write_wifi_chan",
+        "wifi_track_pll",
+    ],
     "crypto_math": [
         "ecp_",
         "bignum_",
@@ -231,13 +285,36 @@ SYMBOL_PATTERNS = {
         "p_256_init_curve",
         "shift_sub_rows",
         "rshift",
+        "rijndaelEncrypt",  # AES Rijndael encryption
+    ],
+    # System and Arduino core functions must come before libc
+    "esp_system": [
+        "system_",  # ESP system functions
+        "postmortem_",  # Postmortem reporting
+    ],
+    "arduino_core": [
+        "pinMode",
+        "resetPins",
+        "millis",
+        "micros",
+        "delay(",  # More specific - Arduino delay function with parenthesis
+        "delayMicroseconds",
+        "digitalWrite",
+        "digitalRead",
+    ],
+    "sntp": ["sntp_", "sntp_recv"],
+    "scheduler": [
+        "run_scheduled_",
+        "compute_scheduled_",
+        "event_TaskQueue",
     ],
     "hw_crypto": ["esp_aes", "esp_sha", "esp_rsa", "esp_bignum", "esp_mpi"],
     "libc": [
         "printf",
         "scanf",
         "malloc",
-        "free",
+        "_free",  # More specific than "free" to match _free, __free_r, etc. but not arbitrary "free" substring
+        "umm_free",  # UMM malloc free function
         "memcpy",
         "memset",
         "strcpy",
@@ -259,7 +336,7 @@ SYMBOL_PATTERNS = {
         "_setenv_r",
         "_tzset_unlocked_r",
         "__tzcalc_limits",
-        "select",
+        "_select",  # More specific than "select" to avoid matching "dhcp_select", etc.
         "scalbnf",
         "strtof",
         "strtof_l",
@@ -316,8 +393,24 @@ SYMBOL_PATTERNS = {
         "CSWTCH$",
         "dst$",
         "sulp",
+        "_strtol_l",  # String to long with locale
+        "__cvt",  # Convert
+        "__utoa",  # Unsigned to ASCII
+        "__global_locale",  # Global locale
+        "_ctype_",  # Character type
+        "impure_data",  # Impure data
+    ],
+    "string_ops": [
+        "strcmp",
+        "strncmp",
+        "strchr",
+        "strstr",
+        "strtok",
+        "strdup",
+        "strncasecmp_P",  # String compare (case insensitive, from program memory)
+        "strnlen_P",  # String length (from program memory)
+        "strncat_P",  # String concatenate (from program memory)
     ],
-    "string_ops": ["strcmp", "strncmp", "strchr", "strstr", "strtok", "strdup"],
     "memory_alloc": ["malloc", "calloc", "realloc", "free", "_sbrk"],
     "file_io": [
         "fread",
@@ -338,10 +431,26 @@ SYMBOL_PATTERNS = {
         "vsscanf",
     ],
     "cpp_anonymous": ["_GLOBAL__N_", "n$"],
-    "cpp_runtime": ["__cxx", "_ZN", "_ZL", "_ZSt", "__gxx_personality", "_Z16"],
-    "exception_handling": ["__cxa_", "_Unwind_", "__gcc_personality", "uw_frame_state"],
+    # Plain C patterns only - C++ symbols will be categorized via DEMANGLED_PATTERNS
+    "nvs": ["nvs_"],  # Plain C NVS functions
+    "ota": ["ota_", "OTA", "esp_ota", "app_desc"],
+    # cpp_runtime: Removed _ZN, _ZL to let DEMANGLED_PATTERNS categorize C++ symbols properly
+    # Only keep patterns that are truly runtime-specific and not categorizable by namespace
+    "cpp_runtime": ["__cxx", "_ZSt", "__gxx_personality", "_Z16"],
+    "exception_handling": [
+        "__cxa_",
+        "_Unwind_",
+        "__gcc_personality",
+        "uw_frame_state",
+        "search_object",  # Search for exception handling object
+        "get_cie_encoding",  # Get CIE encoding
+        "add_fdes",  # Add frame description entries
+        "fde_unencoded_compare",  # Compare FDEs
+        "fde_mixed_encoding_compare",  # Compare mixed encoding FDEs
+        "frame_downheap",  # Frame heap operations
+        "frame_heapsort",  # Frame heap sorting
+    ],
     "static_init": ["_GLOBAL__sub_I_"],
-    "mdns_lib": ["mdns"],
     "phy_radio": [
         "phy_",
         "rf_",
@@ -394,10 +503,47 @@ SYMBOL_PATTERNS = {
         "txcal_debuge_mode",
         "ant_wifitx_cfg",
         "reg_init_begin",
+        "tx_cap_init",  # TX capacitance init
+        "ram_set_txcap",  # RAM TX capacitance setting
+        "tx_atten_",  # TX attenuation
+        "txiq_",  # TX I/Q calibration
+        "ram_cal_",  # RAM calibration
+        "ram_rxiq_",  # RAM RX I/Q
+        "readvdd33",  # Read VDD33
+        "test_tout",  # Test timeout
+        "tsen_meas",  # Temperature sensor measurement
+        "bbpll_cal",  # Baseband PLL calibration
+        "set_cal_",  # Set calibration
+        "set_rfanagain_",  # Set RF analog gain
+        "set_txdc_",  # Set TX DC
+        "get_vdd33_",  # Get VDD33
+        "gen_rx_gain_table",  # Generate RX gain table
+        "ram_ana_inf_gating_en",  # RAM analog interface gating enable
+        "tx_cont_en",  # TX continuous enable
+        "tx_delay_cfg",  # TX delay configuration
+        "tx_gain_table_set",  # TX gain table set
+        "check_and_reset_hw_deadlock",  # Hardware deadlock check
+        "s_config",  # System/hardware config
+        "chan14_mic_cfg",  # Channel 14 MIC config
+    ],
+    "wifi_phy_pp": [
+        "pp_",
+        "ppT",
+        "ppR",
+        "ppP",
+        "ppInstall",
+        "ppCalTxAMPDULength",
+        "ppCheckTx",  # Packet processor TX check
+        "ppCal",  # Packet processor calibration
+        "HdlAllBuffedEb",  # Handle buffered EB
     ],
-    "wifi_phy_pp": ["pp_", "ppT", "ppR", "ppP", "ppInstall", "ppCalTxAMPDULength"],
     "wifi_lmac": ["lmac"],
-    "wifi_device": ["wdev", "wDev_"],
+    "wifi_device": [
+        "wdev",
+        "wDev_",
+        "ic_set_sta",  # Set station mode
+        "ic_set_vif",  # Set virtual interface
+    ],
     "power_mgmt": [
         "pm_",
         "sleep",
@@ -406,15 +552,7 @@ SYMBOL_PATTERNS = {
         "deep_sleep",
         "power_down",
         "g_pm",
-    ],
-    "memory_mgmt": [
-        "mem_",
-        "memory_",
-        "tlsf_",
-        "memp_",
-        "pbuf_",
-        "pbuf_alloc",
-        "pbuf_copy_partial_pbuf",
+        "pmc",  # Power Management Controller
     ],
     "hal_layer": ["hal_"],
     "clock_mgmt": [
@@ -439,7 +577,6 @@ SYMBOL_PATTERNS = {
     "error_handling": ["panic", "abort", "assert", "error_", "fault"],
     "authentication": ["auth"],
     "ppp_protocol": ["ppp", "ipcp_", "lcp_", "chap_", "LcpEchoCheck"],
-    "dhcp": ["dhcp", "handle_dhcp"],
     "ethernet_phy": [
         "emac_",
         "eth_phy_",
@@ -618,7 +755,15 @@ SYMBOL_PATTERNS = {
         "ampdu_dispatch_upto",
     ],
     "ieee802_11": ["ieee802_11_", "ieee802_11_parse_elems"],
-    "rate_control": ["rssi_margin", "rcGetSched", "get_rate_fcc_index"],
+    "rate_control": [
+        "rssi_margin",
+        "rcGetSched",
+        "get_rate_fcc_index",
+        "rcGetRate",  # Get rate
+        "rc_get_",  # Rate control getters
+        "rc_set_",  # Rate control setters
+        "rc_enable_",  # Rate control enable functions
+    ],
     "nan": ["nan_dp_", "nan_dp_post_tx", "nan_dp_delete_peer"],
     "channel_mgmt": ["chm_init", "chm_set_current_channel"],
     "trace": ["trc_init", "trc_onAmpduOp"],
@@ -799,31 +944,18 @@ SYMBOL_PATTERNS = {
         "supports_interlaced_inquiry_scan",
         "supports_reading_remote_extended_features",
     ],
-    "bluetooth_ll": [
-        "lld_pdu_",
-        "ld_acl_",
-        "lld_stop_ind_handler",
-        "lld_evt_winsize_change",
-        "config_lld_evt_funcs_reset",
-        "config_lld_funcs_reset",
-        "config_llm_funcs_reset",
-        "llm_set_long_adv_data",
-        "lld_retry_tx_prog",
-        "llc_link_sup_to_ind_handler",
-        "config_llc_funcs_reset",
-        "lld_evt_rxwin_compute",
-        "config_btdm_funcs_reset",
-        "config_ea_funcs_reset",
-        "llc_defalut_state_tab_reset",
-        "config_rwip_funcs_reset",
-        "ke_lmp_rx_flooding_detect",
-    ],
 }
 
 # Demangled patterns: patterns found in demangled C++ names
 DEMANGLED_PATTERNS = {
     "gpio_driver": ["GPIO"],
     "uart_driver": ["UART"],
+    # mdns_lib must come before network_stack to avoid "udp" matching "_udpReadBuffer" in MDNSResponder
+    "mdns_lib": [
+        "MDNSResponder",
+        "MDNSImplementation",
+        "MDNS",
+    ],
     "network_stack": [
         "lwip",
         "tcp",
@@ -836,6 +968,24 @@ DEMANGLED_PATTERNS = {
         "ethernet",
         "ppp",
         "slip",
+        "UdpContext",  # UDP context class
+        "DhcpServer",  # DHCP server class
+    ],
+    "arduino_core": [
+        "String::",  # Arduino String class
+        "Print::",  # Arduino Print class
+        "HardwareSerial::",  # Serial class
+        "IPAddress::",  # IP address class
+        "EspClass::",  # ESP class
+        "experimental::_SPI",  # Experimental SPI
+    ],
+    "ota": [
+        "UpdaterClass",
+        "Updater::",
+    ],
+    "wifi": [
+        "ESP8266WiFi",
+        "WiFi::",
     ],
     "wifi_stack": ["NetworkInterface"],
     "nimble_bt": [
@@ -854,7 +1004,6 @@ DEMANGLED_PATTERNS = {
     "rtti": ["__type_info", "__class_type_info"],
     "web_server_lib": ["AsyncWebServer", "AsyncWebHandler", "WebServer"],
     "async_tcp": ["AsyncClient", "AsyncServer"],
-    "mdns_lib": ["mdns"],
     "json_lib": [
         "ArduinoJson",
         "JsonDocument",

esphome/automation.py

@@ -16,7 +16,12 @@ from esphome.const import (
     CONF_UPDATE_INTERVAL,
 )
 from esphome.core import ID
-from esphome.cpp_generator import MockObj, MockObjClass, TemplateArgsType
+from esphome.cpp_generator import (
+    LambdaExpression,
+    MockObj,
+    MockObjClass,
+    TemplateArgsType,
+)
 from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
 from esphome.types import ConfigType
 from esphome.util import Registry
@@ -87,6 +92,7 @@ def validate_potentially_or_condition(value):
 
 DelayAction = cg.esphome_ns.class_("DelayAction", Action, cg.Component)
 LambdaAction = cg.esphome_ns.class_("LambdaAction", Action)
+StatelessLambdaAction = cg.esphome_ns.class_("StatelessLambdaAction", Action)
 IfAction = cg.esphome_ns.class_("IfAction", Action)
 WhileAction = cg.esphome_ns.class_("WhileAction", Action)
 RepeatAction = cg.esphome_ns.class_("RepeatAction", Action)
@@ -97,9 +103,40 @@ ResumeComponentAction = cg.esphome_ns.class_("ResumeComponentAction", Action)
 Automation = cg.esphome_ns.class_("Automation")
 
 LambdaCondition = cg.esphome_ns.class_("LambdaCondition", Condition)
+StatelessLambdaCondition = cg.esphome_ns.class_("StatelessLambdaCondition", Condition)
 ForCondition = cg.esphome_ns.class_("ForCondition", Condition, cg.Component)
 
 
+def new_lambda_pvariable(
+    id_obj: ID,
+    lambda_expr: LambdaExpression,
+    stateless_class: MockObjClass,
+    template_arg: cg.TemplateArguments | None = None,
+) -> MockObj:
+    """Create Pvariable for lambda, using stateless class if applicable.
+
+    Combines ID selection and Pvariable creation in one call. For stateless
+    lambdas (empty capture), uses function pointer instead of std::function.
+
+    Args:
+        id_obj: The ID object (action_id, condition_id, or filter_id)
+        lambda_expr: The lambda expression object
+        stateless_class: The stateless class to use for stateless lambdas
+        template_arg: Optional template arguments (for actions/conditions)
+
+    Returns:
+        The created Pvariable
+    """
+    # For stateless lambdas, use function pointer instead of std::function
+    if lambda_expr.capture == "":
+        id_obj = id_obj.copy()
+        id_obj.type = stateless_class
+
+    if template_arg is not None:
+        return cg.new_Pvariable(id_obj, template_arg, lambda_expr)
+    return cg.new_Pvariable(id_obj, lambda_expr)
+
+
 def validate_automation(extra_schema=None, extra_validators=None, single=False):
     if extra_schema is None:
         extra_schema = {}
@@ -240,7 +277,9 @@ async def lambda_condition_to_code(
     args: TemplateArgsType,
 ) -> MockObj:
     lambda_ = await cg.process_lambda(config, args, return_type=bool)
-    return cg.new_Pvariable(condition_id, template_arg, lambda_)
+    return new_lambda_pvariable(
+        condition_id, lambda_, StatelessLambdaCondition, template_arg
+    )
 
 
 @register_condition(
@@ -406,7 +445,7 @@ async def lambda_action_to_code(
     args: TemplateArgsType,
 ) -> MockObj:
     lambda_ = await cg.process_lambda(config, args, return_type=cg.void)
-    return cg.new_Pvariable(action_id, template_arg, lambda_)
+    return new_lambda_pvariable(action_id, lambda_, StatelessLambdaAction, template_arg)
 
 
 @register_action(

esphome/codegen.py

@@ -62,6 +62,7 @@ from esphome.cpp_types import (  # noqa: F401
     EntityBase,
     EntityCategory,
     ESPTime,
+    FixedVector,
     GPIOPin,
     InternalGPIOPin,
     JsonObject,

esphome/components/adalight/adalight_light_effect.cpp

@@ -9,7 +9,7 @@ static const char *const TAG = "adalight_light_effect";
 static const uint32_t ADALIGHT_ACK_INTERVAL = 1000;
 static const uint32_t ADALIGHT_RECEIVE_TIMEOUT = 1000;
 
-AdalightLightEffect::AdalightLightEffect(const std::string &name) : AddressableLightEffect(name) {}
+AdalightLightEffect::AdalightLightEffect(const char *name) : AddressableLightEffect(name) {}
 
 void AdalightLightEffect::start() {
   AddressableLightEffect::start();

esphome/components/adalight/adalight_light_effect.h

@@ -11,7 +11,7 @@ namespace adalight {
 
 class AdalightLightEffect : public light::AddressableLightEffect, public uart::UARTDevice {
  public:
-  AdalightLightEffect(const std::string &name);
+  AdalightLightEffect(const char *name);
 
   void start() override;
   void stop() override;

esphome/components/api/__init__.py

@@ -71,10 +71,12 @@ SERVICE_ARG_NATIVE_TYPES = {
     "int": cg.int32,
     "float": float,
     "string": cg.std_string,
-    "bool[]": cg.std_vector.template(bool),
-    "int[]": cg.std_vector.template(cg.int32),
-    "float[]": cg.std_vector.template(float),
-    "string[]": cg.std_vector.template(cg.std_string),
+    "bool[]": cg.FixedVector.template(bool).operator("const").operator("ref"),
+    "int[]": cg.FixedVector.template(cg.int32).operator("const").operator("ref"),
+    "float[]": cg.FixedVector.template(float).operator("const").operator("ref"),
+    "string[]": cg.FixedVector.template(cg.std_string)
+    .operator("const")
+    .operator("ref"),
 }
 CONF_ENCRYPTION = "encryption"
 CONF_BATCH_DELAY = "batch_delay"
@@ -258,6 +260,10 @@ async def to_code(config):
     if config.get(CONF_ACTIONS) or config[CONF_CUSTOM_SERVICES]:
         cg.add_define("USE_API_SERVICES")
 
+    # Set USE_API_CUSTOM_SERVICES if external components need dynamic service registration
+    if config[CONF_CUSTOM_SERVICES]:
+        cg.add_define("USE_API_CUSTOM_SERVICES")
+
     if config[CONF_HOMEASSISTANT_SERVICES]:
         cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
 
@@ -265,6 +271,8 @@ async def to_code(config):
         cg.add_define("USE_API_HOMEASSISTANT_STATES")
 
     if actions := config.get(CONF_ACTIONS, []):
+        # Collect all triggers first, then register all at once with initializer_list
+        triggers: list[cg.Pvariable] = []
         for conf in actions:
             template_args = []
             func_args = []
@@ -278,8 +286,10 @@ async def to_code(config):
             trigger = cg.new_Pvariable(
                 conf[CONF_TRIGGER_ID], templ, conf[CONF_ACTION], service_arg_names
             )
-            cg.add(var.register_user_service(trigger))
+            triggers.append(trigger)
             await automation.build_automation(trigger, func_args, conf)
+        # Register all services at once - single allocation, no reallocations
+        cg.add(var.initialize_user_services(triggers))
 
     if CONF_ON_CLIENT_CONNECTED in config:
         cg.add_define("USE_API_CLIENT_CONNECTED_TRIGGER")

esphome/components/api/api.proto

@@ -989,7 +989,7 @@ message ListEntitiesClimateResponse {
 
   bool supports_current_temperature = 5; // Deprecated: use feature_flags
   bool supports_two_point_target_temperature = 6; // Deprecated: use feature_flags
-  repeated ClimateMode supported_modes = 7 [(container_pointer) = "std::set<climate::ClimateMode>"];
+  repeated ClimateMode supported_modes = 7 [(container_pointer_no_template) = "climate::ClimateModeMask"];
   float visual_min_temperature = 8;
   float visual_max_temperature = 9;
   float visual_target_temperature_step = 10;
@@ -998,11 +998,11 @@ message ListEntitiesClimateResponse {
   // Deprecated in API version 1.5
   bool legacy_supports_away = 11 [deprecated=true];
   bool supports_action = 12; // Deprecated: use feature_flags
-  repeated ClimateFanMode supported_fan_modes = 13 [(container_pointer) = "std::set<climate::ClimateFanMode>"];
-  repeated ClimateSwingMode supported_swing_modes = 14 [(container_pointer) = "std::set<climate::ClimateSwingMode>"];
-  repeated string supported_custom_fan_modes = 15 [(container_pointer) = "std::set"];
-  repeated ClimatePreset supported_presets = 16 [(container_pointer) = "std::set<climate::ClimatePreset>"];
-  repeated string supported_custom_presets = 17 [(container_pointer) = "std::set"];
+  repeated ClimateFanMode supported_fan_modes = 13 [(container_pointer_no_template) = "climate::ClimateFanModeMask"];
+  repeated ClimateSwingMode supported_swing_modes = 14 [(container_pointer_no_template) = "climate::ClimateSwingModeMask"];
+  repeated string supported_custom_fan_modes = 15 [(container_pointer) = "std::vector"];
+  repeated ClimatePreset supported_presets = 16 [(container_pointer_no_template) = "climate::ClimatePresetMask"];
+  repeated string supported_custom_presets = 17 [(container_pointer) = "std::vector"];
   bool disabled_by_default = 18;
   string icon = 19 [(field_ifdef) = "USE_ENTITY_ICON"];
   EntityCategory entity_category = 20;
@@ -1143,7 +1143,7 @@ message ListEntitiesSelectResponse {
   reserved 4; // Deprecated: was string unique_id
 
   string icon = 5 [(field_ifdef) = "USE_ENTITY_ICON"];
-  repeated string options = 6 [(container_pointer) = "std::vector"];
+  repeated string options = 6 [(container_pointer_no_template) = "FixedVector<const char *>"];
   bool disabled_by_default = 7;
   EntityCategory entity_category = 8;
   uint32 device_id = 9 [(field_ifdef) = "USE_DEVICES"];

esphome/components/api/api_connection.cpp

@@ -486,7 +486,7 @@ uint16_t APIConnection::try_send_light_info(EntityBase *entity, APIConnection *c
   if (light->supports_effects()) {
     msg.effects.emplace_back("None");
     for (auto *effect : light->get_effects()) {
-      msg.effects.push_back(effect->get_name());
+      msg.effects.emplace_back(effect->get_name());
     }
   }
   return fill_and_encode_entity_info(light, msg, ListEntitiesLightResponse::MESSAGE_TYPE, conn, remaining_size,
@@ -669,18 +669,18 @@ uint16_t APIConnection::try_send_climate_info(EntityBase *entity, APIConnection
   msg.supports_action = traits.has_feature_flags(climate::CLIMATE_SUPPORTS_ACTION);
   // Current feature flags and other supported parameters
   msg.feature_flags = traits.get_feature_flags();
-  msg.supported_modes = &traits.get_supported_modes_for_api_();
+  msg.supported_modes = &traits.get_supported_modes();
   msg.visual_min_temperature = traits.get_visual_min_temperature();
   msg.visual_max_temperature = traits.get_visual_max_temperature();
   msg.visual_target_temperature_step = traits.get_visual_target_temperature_step();
   msg.visual_current_temperature_step = traits.get_visual_current_temperature_step();
   msg.visual_min_humidity = traits.get_visual_min_humidity();
   msg.visual_max_humidity = traits.get_visual_max_humidity();
-  msg.supported_fan_modes = &traits.get_supported_fan_modes_for_api_();
-  msg.supported_custom_fan_modes = &traits.get_supported_custom_fan_modes_for_api_();
-  msg.supported_presets = &traits.get_supported_presets_for_api_();
-  msg.supported_custom_presets = &traits.get_supported_custom_presets_for_api_();
-  msg.supported_swing_modes = &traits.get_supported_swing_modes_for_api_();
+  msg.supported_fan_modes = &traits.get_supported_fan_modes();
+  msg.supported_custom_fan_modes = &traits.get_supported_custom_fan_modes();
+  msg.supported_presets = &traits.get_supported_presets();
+  msg.supported_custom_presets = &traits.get_supported_custom_presets();
+  msg.supported_swing_modes = &traits.get_supported_swing_modes();
   return fill_and_encode_entity_info(climate, msg, ListEntitiesClimateResponse::MESSAGE_TYPE, conn, remaining_size,
                                      is_single);
 }
@@ -1572,7 +1572,13 @@ bool APIConnection::send_noise_encryption_set_key_response(const NoiseEncryption
   resp.success = false;
 
   psk_t psk{};
-  if (base64_decode(msg.key, psk.data(), msg.key.size()) != psk.size()) {
+  if (msg.key.empty()) {
+    if (this->parent_->clear_noise_psk(true)) {
+      resp.success = true;
+    } else {
+      ESP_LOGW(TAG, "Failed to clear encryption key");
+    }
+  } else if (base64_decode(msg.key, psk.data(), msg.key.size()) != psk.size()) {
     ESP_LOGW(TAG, "Invalid encryption key length");
   } else if (!this->parent_->save_noise_psk(psk, true)) {
     ESP_LOGW(TAG, "Failed to save encryption key");

esphome/components/api/api_pb2.cpp

@@ -1475,8 +1475,8 @@ void ListEntitiesSelectResponse::encode(ProtoWriteBuffer buffer) const {
 #ifdef USE_ENTITY_ICON
   buffer.encode_string(5, this->icon_ref_);
 #endif
-  for (const auto &it : *this->options) {
-    buffer.encode_string(6, it, true);
+  for (const char *it : *this->options) {
+    buffer.encode_string(6, it, strlen(it), true);
   }
   buffer.encode_bool(7, this->disabled_by_default);
   buffer.encode_uint32(8, static_cast<uint32_t>(this->entity_category));
@@ -1492,8 +1492,8 @@ void ListEntitiesSelectResponse::calculate_size(ProtoSize &size) const {
   size.add_length(1, this->icon_ref_.size());
 #endif
   if (!this->options->empty()) {
-    for (const auto &it : *this->options) {
-      size.add_length_force(1, it.size());
+    for (const char *it : *this->options) {
+      size.add_length_force(1, strlen(it));
     }
   }
   size.add_bool(1, this->disabled_by_default);

esphome/components/api/api_pb2.h

@@ -1377,16 +1377,16 @@ class ListEntitiesClimateResponse final : public InfoResponseProtoMessage {
 #endif
   bool supports_current_temperature{false};
   bool supports_two_point_target_temperature{false};
-  const std::set<climate::ClimateMode> *supported_modes{};
+  const climate::ClimateModeMask *supported_modes{};
   float visual_min_temperature{0.0f};
   float visual_max_temperature{0.0f};
   float visual_target_temperature_step{0.0f};
   bool supports_action{false};
-  const std::set<climate::ClimateFanMode> *supported_fan_modes{};
-  const std::set<climate::ClimateSwingMode> *supported_swing_modes{};
-  const std::set<std::string> *supported_custom_fan_modes{};
-  const std::set<climate::ClimatePreset> *supported_presets{};
-  const std::set<std::string> *supported_custom_presets{};
+  const climate::ClimateFanModeMask *supported_fan_modes{};
+  const climate::ClimateSwingModeMask *supported_swing_modes{};
+  const std::vector<std::string> *supported_custom_fan_modes{};
+  const climate::ClimatePresetMask *supported_presets{};
+  const std::vector<std::string> *supported_custom_presets{};
   float visual_current_temperature_step{0.0f};
   bool supports_current_humidity{false};
   bool supports_target_humidity{false};
@@ -1534,7 +1534,7 @@ class ListEntitiesSelectResponse final : public InfoResponseProtoMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "list_entities_select_response"; }
 #endif
-  const std::vector<std::string> *options{};
+  const FixedVector<const char *> *options{};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP

esphome/components/api/api_pb2_dump.cpp

@@ -88,6 +88,12 @@ static void dump_field(std::string &out, const char *field_name, StringRef value
   out.append("\n");
 }
 
+static void dump_field(std::string &out, const char *field_name, const char *value, int indent = 2) {
+  append_field_prefix(out, field_name, indent);
+  out.append("'").append(value).append("'");
+  out.append("\n");
+}
+
 template<typename T> static void dump_field(std::string &out, const char *field_name, T value, int indent = 2) {
   append_field_prefix(out, field_name, indent);
   out.append(proto_enum_to_string<T>(value));

esphome/components/api/api_server.cpp

@@ -468,6 +468,31 @@ uint16_t APIServer::get_port() const { return this->port_; }
 void APIServer::set_reboot_timeout(uint32_t reboot_timeout) { this->reboot_timeout_ = reboot_timeout; }
 
 #ifdef USE_API_NOISE
+bool APIServer::update_noise_psk_(const SavedNoisePsk &new_psk, const LogString *save_log_msg,
+                                  const LogString *fail_log_msg, const psk_t &active_psk, bool make_active) {
+  if (!this->noise_pref_.save(&new_psk)) {
+    ESP_LOGW(TAG, "%s", LOG_STR_ARG(fail_log_msg));
+    return false;
+  }
+  // ensure it's written immediately
+  if (!global_preferences->sync()) {
+    ESP_LOGW(TAG, "Failed to sync preferences");
+    return false;
+  }
+  ESP_LOGD(TAG, "%s", LOG_STR_ARG(save_log_msg));
+  if (make_active) {
+    this->set_timeout(100, [this, active_psk]() {
+      ESP_LOGW(TAG, "Disconnecting all clients to reset PSK");
+      this->set_noise_psk(active_psk);
+      for (auto &c : this->clients_) {
+        DisconnectRequest req;
+        c->send_message(req, DisconnectRequest::MESSAGE_TYPE);
+      }
+    });
+  }
+  return true;
+}
+
 bool APIServer::save_noise_psk(psk_t psk, bool make_active) {
 #ifdef USE_API_NOISE_PSK_FROM_YAML
   // When PSK is set from YAML, this function should never be called
@@ -482,27 +507,21 @@ bool APIServer::save_noise_psk(psk_t psk, bool make_active) {
   }
 
   SavedNoisePsk new_saved_psk{psk};
-  if (!this->noise_pref_.save(&new_saved_psk)) {
-    ESP_LOGW(TAG, "Failed to save Noise PSK");
-    return false;
-  }
-  // ensure it's written immediately
-  if (!global_preferences->sync()) {
-    ESP_LOGW(TAG, "Failed to sync preferences");
-    return false;
-  }
-  ESP_LOGD(TAG, "Noise PSK saved");
-  if (make_active) {
-    this->set_timeout(100, [this, psk]() {
-      ESP_LOGW(TAG, "Disconnecting all clients to reset PSK");
-      this->set_noise_psk(psk);
-      for (auto &c : this->clients_) {
-        DisconnectRequest req;
-        c->send_message(req, DisconnectRequest::MESSAGE_TYPE);
-      }
-    });
-  }
-  return true;
+  return this->update_noise_psk_(new_saved_psk, LOG_STR("Noise PSK saved"), LOG_STR("Failed to save Noise PSK"), psk,
+                                 make_active);
+#endif
+}
+bool APIServer::clear_noise_psk(bool make_active) {
+#ifdef USE_API_NOISE_PSK_FROM_YAML
+  // When PSK is set from YAML, this function should never be called
+  // but if it is, reject the change
+  ESP_LOGW(TAG, "Key set in YAML");
+  return false;
+#else
+  SavedNoisePsk empty_psk{};
+  psk_t empty{};
+  return this->update_noise_psk_(empty_psk, LOG_STR("Noise PSK cleared"), LOG_STR("Failed to clear Noise PSK"), empty,
+                                 make_active);
 #endif
 }
 #endif

esphome/components/api/api_server.h

@@ -53,6 +53,7 @@ class APIServer : public Component, public Controller {
 
 #ifdef USE_API_NOISE
   bool save_noise_psk(psk_t psk, bool make_active = true);
+  bool clear_noise_psk(bool make_active = true);
   void set_noise_psk(psk_t psk) { noise_ctx_->set_psk(psk); }
   std::shared_ptr<APINoiseContext> get_noise_ctx() { return noise_ctx_; }
 #endif  // USE_API_NOISE
@@ -124,8 +125,14 @@ class APIServer : public Component, public Controller {
 #endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
 #endif  // USE_API_HOMEASSISTANT_SERVICES
 #ifdef USE_API_SERVICES
+  void initialize_user_services(std::initializer_list<UserServiceDescriptor *> services) {
+    this->user_services_.assign(services);
+  }
+#ifdef USE_API_CUSTOM_SERVICES
+  // Only compile push_back method when custom_services: true (external components)
   void register_user_service(UserServiceDescriptor *descriptor) { this->user_services_.push_back(descriptor); }
 #endif
+#endif
 #ifdef USE_HOMEASSISTANT_TIME
   void request_time();
 #endif
@@ -174,6 +181,10 @@ class APIServer : public Component, public Controller {
 
  protected:
   void schedule_reboot_timeout_();
+#ifdef USE_API_NOISE
+  bool update_noise_psk_(const SavedNoisePsk &new_psk, const LogString *save_log_msg, const LogString *fail_log_msg,
+                         const psk_t &active_psk, bool make_active);
+#endif  // USE_API_NOISE
   // Pointers and pointer-like types first (4 bytes each)
   std::unique_ptr<socket::Socket> socket_ = nullptr;
 #ifdef USE_API_CLIENT_CONNECTED_TRIGGER

esphome/components/api/custom_api_device.h

@@ -53,8 +53,14 @@ class CustomAPIDevice {
   template<typename T, typename... Ts>
   void register_service(void (T::*callback)(Ts...), const std::string &name,
                         const std::array<std::string, sizeof...(Ts)> &arg_names) {
+#ifdef USE_API_CUSTOM_SERVICES
     auto *service = new CustomAPIDeviceService<T, Ts...>(name, arg_names, (T *) this, callback);  // NOLINT
     global_api_server->register_user_service(service);
+#else
+    static_assert(
+        sizeof(T) == 0,
+        "register_service() requires 'custom_services: true' in the 'api:' section of your YAML configuration");
+#endif
   }
 #else
   template<typename T, typename... Ts>
@@ -86,8 +92,14 @@ class CustomAPIDevice {
    */
 #ifdef USE_API_SERVICES
   template<typename T> void register_service(void (T::*callback)(), const std::string &name) {
+#ifdef USE_API_CUSTOM_SERVICES
     auto *service = new CustomAPIDeviceService<T>(name, {}, (T *) this, callback);  // NOLINT
     global_api_server->register_user_service(service);
+#else
+    static_assert(
+        sizeof(T) == 0,
+        "register_service() requires 'custom_services: true' in the 'api:' section of your YAML configuration");
+#endif
   }
 #else
   template<typename T> void register_service(void (T::*callback)(), const std::string &name) {

esphome/components/api/user_services.cpp

@@ -11,23 +11,58 @@ template<> int32_t get_execute_arg_value<int32_t>(const ExecuteServiceArgument &
 }
 template<> float get_execute_arg_value<float>(const ExecuteServiceArgument &arg) { return arg.float_; }
 template<> std::string get_execute_arg_value<std::string>(const ExecuteServiceArgument &arg) { return arg.string_; }
+
+// Legacy std::vector versions for external components using custom_api_device.h - optimized with reserve
 template<> std::vector<bool> get_execute_arg_value<std::vector<bool>>(const ExecuteServiceArgument &arg) {
-  return std::vector<bool>(arg.bool_array.begin(), arg.bool_array.end());
+  std::vector<bool> result;
+  result.reserve(arg.bool_array.size());
+  result.insert(result.end(), arg.bool_array.begin(), arg.bool_array.end());
+  return result;
 }
 template<> std::vector<int32_t> get_execute_arg_value<std::vector<int32_t>>(const ExecuteServiceArgument &arg) {
-  return std::vector<int32_t>(arg.int_array.begin(), arg.int_array.end());
+  std::vector<int32_t> result;
+  result.reserve(arg.int_array.size());
+  result.insert(result.end(), arg.int_array.begin(), arg.int_array.end());
+  return result;
 }
 template<> std::vector<float> get_execute_arg_value<std::vector<float>>(const ExecuteServiceArgument &arg) {
-  return std::vector<float>(arg.float_array.begin(), arg.float_array.end());
+  std::vector<float> result;
+  result.reserve(arg.float_array.size());
+  result.insert(result.end(), arg.float_array.begin(), arg.float_array.end());
+  return result;
 }
 template<> std::vector<std::string> get_execute_arg_value<std::vector<std::string>>(const ExecuteServiceArgument &arg) {
-  return std::vector<std::string>(arg.string_array.begin(), arg.string_array.end());
+  std::vector<std::string> result;
+  result.reserve(arg.string_array.size());
+  result.insert(result.end(), arg.string_array.begin(), arg.string_array.end());
+  return result;
+}
+
+// New FixedVector const reference versions for YAML-generated services - zero-copy
+template<>
+const FixedVector<bool> &get_execute_arg_value<const FixedVector<bool> &>(const ExecuteServiceArgument &arg) {
+  return arg.bool_array;
+}
+template<>
+const FixedVector<int32_t> &get_execute_arg_value<const FixedVector<int32_t> &>(const ExecuteServiceArgument &arg) {
+  return arg.int_array;
+}
+template<>
+const FixedVector<float> &get_execute_arg_value<const FixedVector<float> &>(const ExecuteServiceArgument &arg) {
+  return arg.float_array;
+}
+template<>
+const FixedVector<std::string> &get_execute_arg_value<const FixedVector<std::string> &>(
+    const ExecuteServiceArgument &arg) {
+  return arg.string_array;
 }
 
 template<> enums::ServiceArgType to_service_arg_type<bool>() { return enums::SERVICE_ARG_TYPE_BOOL; }
 template<> enums::ServiceArgType to_service_arg_type<int32_t>() { return enums::SERVICE_ARG_TYPE_INT; }
 template<> enums::ServiceArgType to_service_arg_type<float>() { return enums::SERVICE_ARG_TYPE_FLOAT; }
 template<> enums::ServiceArgType to_service_arg_type<std::string>() { return enums::SERVICE_ARG_TYPE_STRING; }
+
+// Legacy std::vector versions for external components using custom_api_device.h
 template<> enums::ServiceArgType to_service_arg_type<std::vector<bool>>() { return enums::SERVICE_ARG_TYPE_BOOL_ARRAY; }
 template<> enums::ServiceArgType to_service_arg_type<std::vector<int32_t>>() {
   return enums::SERVICE_ARG_TYPE_INT_ARRAY;
@@ -39,4 +74,18 @@ template<> enums::ServiceArgType to_service_arg_type<std::vector<std::string>>()
   return enums::SERVICE_ARG_TYPE_STRING_ARRAY;
 }
 
+// New FixedVector const reference versions for YAML-generated services
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<bool> &>() {
+  return enums::SERVICE_ARG_TYPE_BOOL_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<int32_t> &>() {
+  return enums::SERVICE_ARG_TYPE_INT_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<float> &>() {
+  return enums::SERVICE_ARG_TYPE_FLOAT_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<std::string> &>() {
+  return enums::SERVICE_ARG_TYPE_STRING_ARRAY;
+}
+
 }  // namespace esphome::api

esphome/components/bedjet/bedjet_const.h

@@ -99,9 +99,8 @@ enum BedjetCommand : uint8_t {
 
 static const uint8_t BEDJET_FAN_SPEED_COUNT = 20;
 
-static const char *const BEDJET_FAN_STEP_NAMES[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
+static constexpr const char *const BEDJET_FAN_STEP_NAMES[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
 static const std::string BEDJET_FAN_STEP_NAME_STRINGS[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
-static const std::set<std::string> BEDJET_FAN_STEP_NAMES_SET BEDJET_FAN_STEP_NAMES_;
 
 }  // namespace bedjet
 }  // namespace esphome

esphome/components/bedjet/climate/bedjet_climate.h

@@ -43,7 +43,7 @@ class BedJetClimate : public climate::Climate, public BedJetClient, public Polli
     });
 
     // It would be better if we had a slider for the fan modes.
-    traits.set_supported_custom_fan_modes(BEDJET_FAN_STEP_NAMES_SET);
+    traits.set_supported_custom_fan_modes(BEDJET_FAN_STEP_NAMES);
     traits.set_supported_presets({
         // If we support NONE, then have to decide what happens if the user switches to it (turn off?)
         // climate::CLIMATE_PRESET_NONE,

esphome/components/binary_sensor/__init__.py

@@ -155,6 +155,7 @@ DelayedOffFilter = binary_sensor_ns.class_("DelayedOffFilter", Filter, cg.Compon
 InvertFilter = binary_sensor_ns.class_("InvertFilter", Filter)
 AutorepeatFilter = binary_sensor_ns.class_("AutorepeatFilter", Filter, cg.Component)
 LambdaFilter = binary_sensor_ns.class_("LambdaFilter", Filter)
+StatelessLambdaFilter = binary_sensor_ns.class_("StatelessLambdaFilter", Filter)
 SettleFilter = binary_sensor_ns.class_("SettleFilter", Filter, cg.Component)
 
 _LOGGER = getLogger(__name__)
@@ -264,20 +265,31 @@ async def delayed_off_filter_to_code(config, filter_id):
     ),
 )
 async def autorepeat_filter_to_code(config, filter_id):
-    timings = []
     if len(config) > 0:
-        timings.extend(
-            (conf[CONF_DELAY], conf[CONF_TIME_OFF], conf[CONF_TIME_ON])
-            for conf in config
-        )
-    else:
-        timings.append(
-            (
-                cv.time_period_str_unit(DEFAULT_DELAY).total_milliseconds,
-                cv.time_period_str_unit(DEFAULT_TIME_OFF).total_milliseconds,
-                cv.time_period_str_unit(DEFAULT_TIME_ON).total_milliseconds,
+        timings = [
+            cg.StructInitializer(
+                cg.MockObj("AutorepeatFilterTiming", "esphome::binary_sensor::"),
+                ("delay", conf[CONF_DELAY]),
+                ("time_off", conf[CONF_TIME_OFF]),
+                ("time_on", conf[CONF_TIME_ON]),
             )
-        )
+            for conf in config
+        ]
+    else:
+        timings = [
+            cg.StructInitializer(
+                cg.MockObj("AutorepeatFilterTiming", "esphome::binary_sensor::"),
+                ("delay", cv.time_period_str_unit(DEFAULT_DELAY).total_milliseconds),
+                (
+                    "time_off",
+                    cv.time_period_str_unit(DEFAULT_TIME_OFF).total_milliseconds,
+                ),
+                (
+                    "time_on",
+                    cv.time_period_str_unit(DEFAULT_TIME_ON).total_milliseconds,
+                ),
+            )
+        ]
     var = cg.new_Pvariable(filter_id, timings)
     await cg.register_component(var, {})
     return var
@@ -288,7 +300,7 @@ async def lambda_filter_to_code(config, filter_id):
     lambda_ = await cg.process_lambda(
         config, [(bool, "x")], return_type=cg.optional.template(bool)
     )
-    return cg.new_Pvariable(filter_id, lambda_)
+    return automation.new_lambda_pvariable(filter_id, lambda_, StatelessLambdaFilter)
 
 
 @register_filter(

esphome/components/binary_sensor/automation.h

@@ -2,11 +2,11 @@
 
 #include <cinttypes>
 #include <utility>
-#include <vector>
 
 #include "esphome/core/component.h"
 #include "esphome/core/automation.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
 #include "esphome/components/binary_sensor/binary_sensor.h"
 
 namespace esphome {
@@ -92,8 +92,8 @@ class DoubleClickTrigger : public Trigger<> {
 
 class MultiClickTrigger : public Trigger<>, public Component {
  public:
-  explicit MultiClickTrigger(BinarySensor *parent, std::vector<MultiClickTriggerEvent> timing)
-      : parent_(parent), timing_(std::move(timing)) {}
+  explicit MultiClickTrigger(BinarySensor *parent, std::initializer_list<MultiClickTriggerEvent> timing)
+      : parent_(parent), timing_(timing) {}
 
   void setup() override {
     this->last_state_ = this->parent_->get_state_default(false);
@@ -115,7 +115,7 @@ class MultiClickTrigger : public Trigger<>, public Component {
   void trigger_();
 
   BinarySensor *parent_;
-  std::vector<MultiClickTriggerEvent> timing_;
+  FixedVector<MultiClickTriggerEvent> timing_;
   uint32_t invalid_cooldown_{1000};
   optional<size_t> at_index_{};
   bool last_state_{false};

esphome/components/binary_sensor/binary_sensor.cpp

@@ -51,7 +51,7 @@ void BinarySensor::add_filter(Filter *filter) {
     last_filter->next_ = filter;
   }
 }
-void BinarySensor::add_filters(const std::vector<Filter *> &filters) {
+void BinarySensor::add_filters(std::initializer_list<Filter *> filters) {
   for (Filter *filter : filters) {
     this->add_filter(filter);
   }

esphome/components/binary_sensor/binary_sensor.h

@@ -4,7 +4,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/components/binary_sensor/filter.h"
 
-#include <vector>
+#include <initializer_list>
 
 namespace esphome {
 
@@ -48,7 +48,7 @@ class BinarySensor : public StatefulEntityBase<bool>, public EntityBase_DeviceCl
   void publish_initial_state(bool new_state);
 
   void add_filter(Filter *filter);
-  void add_filters(const std::vector<Filter *> &filters);
+  void add_filters(std::initializer_list<Filter *> filters);
 
   // ========== INTERNAL METHODS ==========
   // (In most use cases you won't need these)

esphome/components/binary_sensor/filter.cpp

@@ -1,7 +1,6 @@
 #include "filter.h"
 
 #include "binary_sensor.h"
-#include <utility>
 
 namespace esphome {
 
@@ -68,7 +67,7 @@ float DelayedOffFilter::get_setup_priority() const { return setup_priority::HARD
 
 optional<bool> InvertFilter::new_value(bool value) { return !value; }
 
-AutorepeatFilter::AutorepeatFilter(std::vector<AutorepeatFilterTiming> timings) : timings_(std::move(timings)) {}
+AutorepeatFilter::AutorepeatFilter(std::initializer_list<AutorepeatFilterTiming> timings) : timings_(timings) {}
 
 optional<bool> AutorepeatFilter::new_value(bool value) {
   if (value) {

esphome/components/binary_sensor/filter.h

@@ -4,8 +4,6 @@
 #include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
 
-#include <vector>
-
 namespace esphome {
 
 namespace binary_sensor {
@@ -82,11 +80,6 @@ class InvertFilter : public Filter {
 };
 
 struct AutorepeatFilterTiming {
-  AutorepeatFilterTiming(uint32_t delay, uint32_t off, uint32_t on) {
-    this->delay = delay;
-    this->time_off = off;
-    this->time_on = on;
-  }
   uint32_t delay;
   uint32_t time_off;
   uint32_t time_on;
@@ -94,7 +87,7 @@ struct AutorepeatFilterTiming {
 
 class AutorepeatFilter : public Filter, public Component {
  public:
-  explicit AutorepeatFilter(std::vector<AutorepeatFilterTiming> timings);
+  explicit AutorepeatFilter(std::initializer_list<AutorepeatFilterTiming> timings);
 
   optional<bool> new_value(bool value) override;
 
@@ -104,7 +97,7 @@ class AutorepeatFilter : public Filter, public Component {
   void next_timing_();
   void next_value_(bool val);
 
-  std::vector<AutorepeatFilterTiming> timings_;
+  FixedVector<AutorepeatFilterTiming> timings_;
   uint8_t active_timing_{0};
 };
 
@@ -118,6 +111,21 @@ class LambdaFilter : public Filter {
   std::function<optional<bool>(bool)> f_;
 };
 
+/** Optimized lambda filter for stateless lambdas (no capture).
+ *
+ * Uses function pointer instead of std::function to reduce memory overhead.
+ * Memory: 4 bytes (function pointer on 32-bit) vs 32 bytes (std::function).
+ */
+class StatelessLambdaFilter : public Filter {
+ public:
+  explicit StatelessLambdaFilter(optional<bool> (*f)(bool)) : f_(f) {}
+
+  optional<bool> new_value(bool value) override { return this->f_(value); }
+
+ protected:
+  optional<bool> (*f_)(bool);
+};
+
 class SettleFilter : public Filter, public Component {
  public:
   optional<bool> new_value(bool value) override;

esphome/components/ble_client/automation.h

@@ -96,8 +96,11 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   BLEClientWriteAction(BLEClient *ble_client) {
     ble_client->register_ble_node(this);
     ble_client_ = ble_client;
+    this->construct_simple_value_();
   }
 
+  ~BLEClientWriteAction() { this->destroy_simple_value_(); }
+
   void set_service_uuid16(uint16_t uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_uint16(uuid); }
   void set_service_uuid32(uint32_t uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_service_uuid128(uint8_t *uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
@@ -106,14 +109,18 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   void set_char_uuid32(uint32_t uuid) { this->char_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_char_uuid128(uint8_t *uuid) { this->char_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
 
-  void set_value_template(std::function<std::vector<uint8_t>(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(std::vector<uint8_t> (*func)(Ts...)) {
+    this->destroy_simple_value_();
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const std::vector<uint8_t> &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    if (!this->has_simple_value_) {
+      this->construct_simple_value_();
+    }
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
   void play(Ts... x) override {}
@@ -121,7 +128,7 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   void play_complex(Ts... x) override {
     this->num_running_++;
     this->var_ = std::make_tuple(x...);
-    auto value = this->has_simple_value_ ? this->value_simple_ : this->value_template_(x...);
+    auto value = this->has_simple_value_ ? this->value_.simple : this->value_.template_func(x...);
     // on write failure, continue the automation chain rather than stopping so that e.g. disconnect can work.
     if (!write(value))
       this->play_next_(x...);
@@ -194,10 +201,22 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   }
 
  private:
+  void construct_simple_value_() { new (&this->value_.simple) std::vector<uint8_t>(); }
+
+  void destroy_simple_value_() {
+    if (this->has_simple_value_) {
+      this->value_.simple.~vector();
+    }
+  }
+
   BLEClient *ble_client_;
   bool has_simple_value_ = true;
-  std::vector<uint8_t> value_simple_;
-  std::function<std::vector<uint8_t>(Ts...)> value_template_{};
+  union Value {
+    std::vector<uint8_t> simple;
+    std::vector<uint8_t> (*template_func)(Ts...);
+    Value() {}   // trivial constructor
+    ~Value() {}  // trivial destructor - we manage lifetime via discriminator
+  } value_;
   espbt::ESPBTUUID service_uuid_;
   espbt::ESPBTUUID char_uuid_;
   std::tuple<Ts...> var_{};
@@ -213,9 +232,9 @@ template<typename... Ts> class BLEClientPasskeyReplyAction : public Action<Ts...
   void play(Ts... x) override {
     uint32_t passkey;
     if (has_simple_value_) {
-      passkey = this->value_simple_;
+      passkey = this->value_.simple;
     } else {
-      passkey = this->value_template_(x...);
+      passkey = this->value_.template_func(x...);
     }
     if (passkey > 999999)
       return;
@@ -224,21 +243,23 @@ template<typename... Ts> class BLEClientPasskeyReplyAction : public Action<Ts...
     esp_ble_passkey_reply(remote_bda, true, passkey);
   }
 
-  void set_value_template(std::function<uint32_t(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(uint32_t (*func)(Ts...)) {
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const uint32_t &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
  private:
   BLEClient *parent_{nullptr};
   bool has_simple_value_ = true;
-  uint32_t value_simple_{0};
-  std::function<uint32_t(Ts...)> value_template_{};
+  union {
+    uint32_t simple;
+    uint32_t (*template_func)(Ts...);
+  } value_{.simple = 0};
 };
 
 template<typename... Ts> class BLEClientNumericComparisonReplyAction : public Action<Ts...> {
@@ -249,27 +270,29 @@ template<typename... Ts> class BLEClientNumericComparisonReplyAction : public Ac
     esp_bd_addr_t remote_bda;
     memcpy(remote_bda, parent_->get_remote_bda(), sizeof(esp_bd_addr_t));
     if (has_simple_value_) {
-      esp_ble_confirm_reply(remote_bda, this->value_simple_);
+      esp_ble_confirm_reply(remote_bda, this->value_.simple);
     } else {
-      esp_ble_confirm_reply(remote_bda, this->value_template_(x...));
+      esp_ble_confirm_reply(remote_bda, this->value_.template_func(x...));
     }
   }
 
-  void set_value_template(std::function<bool(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(bool (*func)(Ts...)) {
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const bool &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
  private:
   BLEClient *parent_{nullptr};
   bool has_simple_value_ = true;
-  bool value_simple_{false};
-  std::function<bool(Ts...)> value_template_{};
+  union {
+    bool simple;
+    bool (*template_func)(Ts...);
+  } value_{.simple = false};
 };
 
 template<typename... Ts> class BLEClientRemoveBondAction : public Action<Ts...> {

esphome/components/ble_client/sensor/ble_sensor.cpp

@@ -117,9 +117,9 @@ void BLESensor::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t ga
 }
 
 float BLESensor::parse_data_(uint8_t *value, uint16_t value_len) {
-  if (this->data_to_value_func_.has_value()) {
+  if (this->has_data_to_value_) {
     std::vector<uint8_t> data(value, value + value_len);
-    return (*this->data_to_value_func_)(data);
+    return this->data_to_value_func_(data);
   } else {
     return value[0];
   }

esphome/components/ble_client/sensor/ble_sensor.h

@@ -15,8 +15,6 @@ namespace ble_client {
 
 namespace espbt = esphome::esp32_ble_tracker;
 
-using data_to_value_t = std::function<float(std::vector<uint8_t>)>;
-
 class BLESensor : public sensor::Sensor, public PollingComponent, public BLEClientNode {
  public:
   void loop() override;
@@ -33,13 +31,17 @@ class BLESensor : public sensor::Sensor, public PollingComponent, public BLEClie
   void set_descr_uuid16(uint16_t uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_uint16(uuid); }
   void set_descr_uuid32(uint32_t uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_descr_uuid128(uint8_t *uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
-  void set_data_to_value(data_to_value_t &&lambda) { this->data_to_value_func_ = lambda; }
+  void set_data_to_value(float (*lambda)(const std::vector<uint8_t> &)) {
+    this->data_to_value_func_ = lambda;
+    this->has_data_to_value_ = true;
+  }
   void set_enable_notify(bool notify) { this->notify_ = notify; }
   uint16_t handle;
 
  protected:
   float parse_data_(uint8_t *value, uint16_t value_len);
-  optional<data_to_value_t> data_to_value_func_{};
+  bool has_data_to_value_{false};
+  float (*data_to_value_func_)(const std::vector<uint8_t> &){};
   bool notify_;
   espbt::ESPBTUUID service_uuid_;
   espbt::ESPBTUUID char_uuid_;

esphome/components/climate/climate.cpp

@@ -385,12 +385,14 @@ void Climate::save_state_() {
   if (!traits.get_supported_custom_fan_modes().empty() && custom_fan_mode.has_value()) {
     state.uses_custom_fan_mode = true;
     const auto &supported = traits.get_supported_custom_fan_modes();
-    std::vector<std::string> vec{supported.begin(), supported.end()};
-    for (size_t i = 0; i < vec.size(); i++) {
-      if (vec[i] == custom_fan_mode) {
+    // std::vector maintains insertion order
+    size_t i = 0;
+    for (const auto &mode : supported) {
+      if (mode == custom_fan_mode) {
         state.custom_fan_mode = i;
         break;
       }
+      i++;
     }
   }
   if (traits.get_supports_presets() && preset.has_value()) {
@@ -400,12 +402,14 @@ void Climate::save_state_() {
   if (!traits.get_supported_custom_presets().empty() && custom_preset.has_value()) {
     state.uses_custom_preset = true;
     const auto &supported = traits.get_supported_custom_presets();
-    std::vector<std::string> vec{supported.begin(), supported.end()};
-    for (size_t i = 0; i < vec.size(); i++) {
-      if (vec[i] == custom_preset) {
+    // std::vector maintains insertion order
+    size_t i = 0;
+    for (const auto &preset : supported) {
+      if (preset == custom_preset) {
         state.custom_preset = i;
         break;
       }
+      i++;
     }
   }
   if (traits.get_supports_swing_modes()) {
@@ -520,13 +524,23 @@ ClimateCall ClimateDeviceRestoreState::to_call(Climate *climate) {
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TARGET_HUMIDITY)) {
     call.set_target_humidity(this->target_humidity);
   }
-  if (traits.get_supports_fan_modes() || !traits.get_supported_custom_fan_modes().empty()) {
+  if (this->uses_custom_fan_mode) {
+    if (this->custom_fan_mode < traits.get_supported_custom_fan_modes().size()) {
+      call.fan_mode_.reset();
+      call.custom_fan_mode_ = *std::next(traits.get_supported_custom_fan_modes().cbegin(), this->custom_fan_mode);
+    }
+  } else if (traits.supports_fan_mode(this->fan_mode)) {
     call.set_fan_mode(this->fan_mode);
   }
-  if (traits.get_supports_presets() || !traits.get_supported_custom_presets().empty()) {
+  if (this->uses_custom_preset) {
+    if (this->custom_preset < traits.get_supported_custom_presets().size()) {
+      call.preset_.reset();
+      call.custom_preset_ = *std::next(traits.get_supported_custom_presets().cbegin(), this->custom_preset);
+    }
+  } else if (traits.supports_preset(this->preset)) {
     call.set_preset(this->preset);
   }
-  if (traits.get_supports_swing_modes()) {
+  if (traits.supports_swing_mode(this->swing_mode)) {
     call.set_swing_mode(this->swing_mode);
   }
   return call;
@@ -545,29 +559,25 @@ void ClimateDeviceRestoreState::apply(Climate *climate) {
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TARGET_HUMIDITY)) {
     climate->target_humidity = this->target_humidity;
   }
-  if (traits.get_supports_fan_modes() && !this->uses_custom_fan_mode) {
+  if (this->uses_custom_fan_mode) {
+    if (this->custom_fan_mode < traits.get_supported_custom_fan_modes().size()) {
+      climate->fan_mode.reset();
+      climate->custom_fan_mode = *std::next(traits.get_supported_custom_fan_modes().cbegin(), this->custom_fan_mode);
+    }
+  } else if (traits.supports_fan_mode(this->fan_mode)) {
     climate->fan_mode = this->fan_mode;
+    climate->custom_fan_mode.reset();
   }
-  if (!traits.get_supported_custom_fan_modes().empty() && this->uses_custom_fan_mode) {
-    // std::set has consistent order (lexicographic for strings), so this is ok
-    const auto &modes = traits.get_supported_custom_fan_modes();
-    std::vector<std::string> modes_vec{modes.begin(), modes.end()};
-    if (custom_fan_mode < modes_vec.size()) {
-      climate->custom_fan_mode = modes_vec[this->custom_fan_mode];
+  if (this->uses_custom_preset) {
+    if (this->custom_preset < traits.get_supported_custom_presets().size()) {
+      climate->preset.reset();
+      climate->custom_preset = *std::next(traits.get_supported_custom_presets().cbegin(), this->custom_preset);
     }
-  }
-  if (traits.get_supports_presets() && !this->uses_custom_preset) {
+  } else if (traits.supports_preset(this->preset)) {
     climate->preset = this->preset;
+    climate->custom_preset.reset();
   }
-  if (!traits.get_supported_custom_presets().empty() && uses_custom_preset) {
-    // std::set has consistent order (lexicographic for strings), so this is ok
-    const auto &presets = traits.get_supported_custom_presets();
-    std::vector<std::string> presets_vec{presets.begin(), presets.end()};
-    if (custom_preset < presets_vec.size()) {
-      climate->custom_preset = presets_vec[this->custom_preset];
-    }
-  }
-  if (traits.get_supports_swing_modes()) {
+  if (traits.supports_swing_mode(this->swing_mode)) {
     climate->swing_mode = this->swing_mode;
   }
   climate->publish_state();

esphome/components/climate/climate.h

@@ -33,6 +33,7 @@ class Climate;
 class ClimateCall {
  public:
   explicit ClimateCall(Climate *parent) : parent_(parent) {}
+  friend struct ClimateDeviceRestoreState;
 
   /// Set the mode of the climate device.
   ClimateCall &set_mode(ClimateMode mode);

esphome/components/climate/climate_mode.h

@@ -7,6 +7,7 @@ namespace esphome {
 namespace climate {
 
 /// Enum for all modes a climate device can be in.
+/// NOTE: If adding values, update ClimateModeMask in climate_traits.h to use the new last value
 enum ClimateMode : uint8_t {
   /// The climate device is off
   CLIMATE_MODE_OFF = 0,
@@ -24,7 +25,7 @@ enum ClimateMode : uint8_t {
    * For example, the target temperature can be adjusted based on a schedule, or learned behavior.
    * The target temperature can't be adjusted when in this mode.
    */
-  CLIMATE_MODE_AUTO = 6
+  CLIMATE_MODE_AUTO = 6  // Update ClimateModeMask in climate_traits.h if adding values after this
 };
 
 /// Enum for the current action of the climate device. Values match those of ClimateMode.
@@ -43,6 +44,7 @@ enum ClimateAction : uint8_t {
   CLIMATE_ACTION_FAN = 6,
 };
 
+/// NOTE: If adding values, update ClimateFanModeMask in climate_traits.h to use the new last value
 enum ClimateFanMode : uint8_t {
   /// The fan mode is set to On
   CLIMATE_FAN_ON = 0,
@@ -63,10 +65,11 @@ enum ClimateFanMode : uint8_t {
   /// The fan mode is set to Diffuse
   CLIMATE_FAN_DIFFUSE = 8,
   /// The fan mode is set to Quiet
-  CLIMATE_FAN_QUIET = 9,
+  CLIMATE_FAN_QUIET = 9,  // Update ClimateFanModeMask in climate_traits.h if adding values after this
 };
 
 /// Enum for all modes a climate swing can be in
+/// NOTE: If adding values, update ClimateSwingModeMask in climate_traits.h to use the new last value
 enum ClimateSwingMode : uint8_t {
   /// The swing mode is set to Off
   CLIMATE_SWING_OFF = 0,
@@ -75,10 +78,11 @@ enum ClimateSwingMode : uint8_t {
   /// The fan mode is set to Vertical
   CLIMATE_SWING_VERTICAL = 2,
   /// The fan mode is set to Horizontal
-  CLIMATE_SWING_HORIZONTAL = 3,
+  CLIMATE_SWING_HORIZONTAL = 3,  // Update ClimateSwingModeMask in climate_traits.h if adding values after this
 };
 
 /// Enum for all preset modes
+/// NOTE: If adding values, update ClimatePresetMask in climate_traits.h to use the new last value
 enum ClimatePreset : uint8_t {
   /// No preset is active
   CLIMATE_PRESET_NONE = 0,
@@ -95,7 +99,7 @@ enum ClimatePreset : uint8_t {
   /// Device is prepared for sleep
   CLIMATE_PRESET_SLEEP = 6,
   /// Device is reacting to activity (e.g., movement sensors)
-  CLIMATE_PRESET_ACTIVITY = 7,
+  CLIMATE_PRESET_ACTIVITY = 7,  // Update ClimatePresetMask in climate_traits.h if adding values after this
 };
 
 enum ClimateFeature : uint32_t {

esphome/components/climate/climate_traits.h

@@ -1,19 +1,33 @@
 #pragma once
 
-#include <set>
+#include <vector>
 #include "climate_mode.h"
+#include "esphome/core/finite_set_mask.h"
 #include "esphome/core/helpers.h"
 
 namespace esphome {
-
-#ifdef USE_API
-namespace api {
-class APIConnection;
-}  // namespace api
-#endif
-
 namespace climate {
 
+// Type aliases for climate enum bitmasks
+// These replace std::set<EnumType> to eliminate red-black tree overhead
+// For contiguous enums starting at 0, DefaultBitPolicy provides 1:1 mapping (enum value = bit position)
+// Bitmask size is automatically calculated from the last enum value
+using ClimateModeMask = FiniteSetMask<ClimateMode, DefaultBitPolicy<ClimateMode, CLIMATE_MODE_AUTO + 1>>;
+using ClimateFanModeMask = FiniteSetMask<ClimateFanMode, DefaultBitPolicy<ClimateFanMode, CLIMATE_FAN_QUIET + 1>>;
+using ClimateSwingModeMask =
+    FiniteSetMask<ClimateSwingMode, DefaultBitPolicy<ClimateSwingMode, CLIMATE_SWING_HORIZONTAL + 1>>;
+using ClimatePresetMask = FiniteSetMask<ClimatePreset, DefaultBitPolicy<ClimatePreset, CLIMATE_PRESET_ACTIVITY + 1>>;
+
+// Lightweight linear search for small vectors (1-20 items)
+// Avoids std::find template overhead
+template<typename T> inline bool vector_contains(const std::vector<T> &vec, const T &value) {
+  for (const auto &item : vec) {
+    if (item == value)
+      return true;
+  }
+  return false;
+}
+
 /** This class contains all static data for climate devices.
  *
  * All climate devices must support these features:
@@ -107,48 +121,60 @@ class ClimateTraits {
     }
   }
 
-  void set_supported_modes(std::set<ClimateMode> modes) { this->supported_modes_ = std::move(modes); }
+  void set_supported_modes(ClimateModeMask modes) { this->supported_modes_ = modes; }
   void add_supported_mode(ClimateMode mode) { this->supported_modes_.insert(mode); }
   bool supports_mode(ClimateMode mode) const { return this->supported_modes_.count(mode); }
-  const std::set<ClimateMode> &get_supported_modes() const { return this->supported_modes_; }
+  const ClimateModeMask &get_supported_modes() const { return this->supported_modes_; }
 
-  void set_supported_fan_modes(std::set<ClimateFanMode> modes) { this->supported_fan_modes_ = std::move(modes); }
+  void set_supported_fan_modes(ClimateFanModeMask modes) { this->supported_fan_modes_ = modes; }
   void add_supported_fan_mode(ClimateFanMode mode) { this->supported_fan_modes_.insert(mode); }
-  void add_supported_custom_fan_mode(const std::string &mode) { this->supported_custom_fan_modes_.insert(mode); }
+  void add_supported_custom_fan_mode(const std::string &mode) { this->supported_custom_fan_modes_.push_back(mode); }
   bool supports_fan_mode(ClimateFanMode fan_mode) const { return this->supported_fan_modes_.count(fan_mode); }
   bool get_supports_fan_modes() const {
     return !this->supported_fan_modes_.empty() || !this->supported_custom_fan_modes_.empty();
   }
-  const std::set<ClimateFanMode> &get_supported_fan_modes() const { return this->supported_fan_modes_; }
+  const ClimateFanModeMask &get_supported_fan_modes() const { return this->supported_fan_modes_; }
 
-  void set_supported_custom_fan_modes(std::set<std::string> supported_custom_fan_modes) {
+  void set_supported_custom_fan_modes(std::vector<std::string> supported_custom_fan_modes) {
     this->supported_custom_fan_modes_ = std::move(supported_custom_fan_modes);
   }
-  const std::set<std::string> &get_supported_custom_fan_modes() const { return this->supported_custom_fan_modes_; }
+  void set_supported_custom_fan_modes(std::initializer_list<std::string> modes) {
+    this->supported_custom_fan_modes_ = modes;
+  }
+  template<size_t N> void set_supported_custom_fan_modes(const char *const (&modes)[N]) {
+    this->supported_custom_fan_modes_.assign(modes, modes + N);
+  }
+  const std::vector<std::string> &get_supported_custom_fan_modes() const { return this->supported_custom_fan_modes_; }
   bool supports_custom_fan_mode(const std::string &custom_fan_mode) const {
-    return this->supported_custom_fan_modes_.count(custom_fan_mode);
+    return vector_contains(this->supported_custom_fan_modes_, custom_fan_mode);
   }
 
-  void set_supported_presets(std::set<ClimatePreset> presets) { this->supported_presets_ = std::move(presets); }
+  void set_supported_presets(ClimatePresetMask presets) { this->supported_presets_ = presets; }
   void add_supported_preset(ClimatePreset preset) { this->supported_presets_.insert(preset); }
-  void add_supported_custom_preset(const std::string &preset) { this->supported_custom_presets_.insert(preset); }
+  void add_supported_custom_preset(const std::string &preset) { this->supported_custom_presets_.push_back(preset); }
   bool supports_preset(ClimatePreset preset) const { return this->supported_presets_.count(preset); }
   bool get_supports_presets() const { return !this->supported_presets_.empty(); }
-  const std::set<climate::ClimatePreset> &get_supported_presets() const { return this->supported_presets_; }
+  const ClimatePresetMask &get_supported_presets() const { return this->supported_presets_; }
 
-  void set_supported_custom_presets(std::set<std::string> supported_custom_presets) {
+  void set_supported_custom_presets(std::vector<std::string> supported_custom_presets) {
     this->supported_custom_presets_ = std::move(supported_custom_presets);
   }
-  const std::set<std::string> &get_supported_custom_presets() const { return this->supported_custom_presets_; }
+  void set_supported_custom_presets(std::initializer_list<std::string> presets) {
+    this->supported_custom_presets_ = presets;
+  }
+  template<size_t N> void set_supported_custom_presets(const char *const (&presets)[N]) {
+    this->supported_custom_presets_.assign(presets, presets + N);
+  }
+  const std::vector<std::string> &get_supported_custom_presets() const { return this->supported_custom_presets_; }
   bool supports_custom_preset(const std::string &custom_preset) const {
-    return this->supported_custom_presets_.count(custom_preset);
+    return vector_contains(this->supported_custom_presets_, custom_preset);
   }
 
-  void set_supported_swing_modes(std::set<ClimateSwingMode> modes) { this->supported_swing_modes_ = std::move(modes); }
+  void set_supported_swing_modes(ClimateSwingModeMask modes) { this->supported_swing_modes_ = modes; }
   void add_supported_swing_mode(ClimateSwingMode mode) { this->supported_swing_modes_.insert(mode); }
   bool supports_swing_mode(ClimateSwingMode swing_mode) const { return this->supported_swing_modes_.count(swing_mode); }
   bool get_supports_swing_modes() const { return !this->supported_swing_modes_.empty(); }
-  const std::set<ClimateSwingMode> &get_supported_swing_modes() const { return this->supported_swing_modes_; }
+  const ClimateSwingModeMask &get_supported_swing_modes() const { return this->supported_swing_modes_; }
 
   float get_visual_min_temperature() const { return this->visual_min_temperature_; }
   void set_visual_min_temperature(float visual_min_temperature) {
@@ -179,23 +205,6 @@ class ClimateTraits {
   void set_visual_max_humidity(float visual_max_humidity) { this->visual_max_humidity_ = visual_max_humidity; }
 
  protected:
-#ifdef USE_API
-  // The API connection is a friend class to access internal methods
-  friend class api::APIConnection;
-  // These methods return references to internal data structures.
-  // They are used by the API to avoid copying data when encoding messages.
-  // Warning: Do not use these methods outside of the API connection code.
-  // They return references to internal data that can be invalidated.
-  const std::set<ClimateMode> &get_supported_modes_for_api_() const { return this->supported_modes_; }
-  const std::set<ClimateFanMode> &get_supported_fan_modes_for_api_() const { return this->supported_fan_modes_; }
-  const std::set<std::string> &get_supported_custom_fan_modes_for_api_() const {
-    return this->supported_custom_fan_modes_;
-  }
-  const std::set<climate::ClimatePreset> &get_supported_presets_for_api_() const { return this->supported_presets_; }
-  const std::set<std::string> &get_supported_custom_presets_for_api_() const { return this->supported_custom_presets_; }
-  const std::set<ClimateSwingMode> &get_supported_swing_modes_for_api_() const { return this->supported_swing_modes_; }
-#endif
-
   void set_mode_support_(climate::ClimateMode mode, bool supported) {
     if (supported) {
       this->supported_modes_.insert(mode);
@@ -226,12 +235,12 @@ class ClimateTraits {
   float visual_min_humidity_{30};
   float visual_max_humidity_{99};
 
-  std::set<climate::ClimateMode> supported_modes_ = {climate::CLIMATE_MODE_OFF};
-  std::set<climate::ClimateFanMode> supported_fan_modes_;
-  std::set<climate::ClimateSwingMode> supported_swing_modes_;
-  std::set<climate::ClimatePreset> supported_presets_;
-  std::set<std::string> supported_custom_fan_modes_;
-  std::set<std::string> supported_custom_presets_;
+  climate::ClimateModeMask supported_modes_{climate::CLIMATE_MODE_OFF};
+  climate::ClimateFanModeMask supported_fan_modes_;
+  climate::ClimateSwingModeMask supported_swing_modes_;
+  climate::ClimatePresetMask supported_presets_;
+  std::vector<std::string> supported_custom_fan_modes_;
+  std::vector<std::string> supported_custom_presets_;
 };
 
 }  // namespace climate

esphome/components/climate_ir/climate_ir.h

@@ -24,16 +24,18 @@ class ClimateIR : public Component,
                   public remote_base::RemoteTransmittable {
  public:
   ClimateIR(float minimum_temperature, float maximum_temperature, float temperature_step = 1.0f,
-            bool supports_dry = false, bool supports_fan_only = false, std::set<climate::ClimateFanMode> fan_modes = {},
-            std::set<climate::ClimateSwingMode> swing_modes = {}, std::set<climate::ClimatePreset> presets = {}) {
+            bool supports_dry = false, bool supports_fan_only = false,
+            climate::ClimateFanModeMask fan_modes = climate::ClimateFanModeMask(),
+            climate::ClimateSwingModeMask swing_modes = climate::ClimateSwingModeMask(),
+            climate::ClimatePresetMask presets = climate::ClimatePresetMask()) {
     this->minimum_temperature_ = minimum_temperature;
     this->maximum_temperature_ = maximum_temperature;
     this->temperature_step_ = temperature_step;
     this->supports_dry_ = supports_dry;
     this->supports_fan_only_ = supports_fan_only;
-    this->fan_modes_ = std::move(fan_modes);
-    this->swing_modes_ = std::move(swing_modes);
-    this->presets_ = std::move(presets);
+    this->fan_modes_ = fan_modes;
+    this->swing_modes_ = swing_modes;
+    this->presets_ = presets;
   }
 
   void setup() override;
@@ -60,9 +62,9 @@ class ClimateIR : public Component,
   bool supports_heat_{true};
   bool supports_dry_{false};
   bool supports_fan_only_{false};
-  std::set<climate::ClimateFanMode> fan_modes_ = {};
-  std::set<climate::ClimateSwingMode> swing_modes_ = {};
-  std::set<climate::ClimatePreset> presets_ = {};
+  climate::ClimateFanModeMask fan_modes_{};
+  climate::ClimateSwingModeMask swing_modes_{};
+  climate::ClimatePresetMask presets_{};
 
   sensor::Sensor *sensor_{nullptr};
 };

esphome/components/e131/e131.cpp

@@ -80,8 +80,8 @@ void E131Component::add_effect(E131AddressableLightEffect *light_effect) {
     return;
   }
 
-  ESP_LOGD(TAG, "Registering '%s' for universes %d-%d.", light_effect->get_name().c_str(),
-           light_effect->get_first_universe(), light_effect->get_last_universe());
+  ESP_LOGD(TAG, "Registering '%s' for universes %d-%d.", light_effect->get_name(), light_effect->get_first_universe(),
+           light_effect->get_last_universe());
 
   light_effects_.insert(light_effect);
 
@@ -95,8 +95,8 @@ void E131Component::remove_effect(E131AddressableLightEffect *light_effect) {
     return;
   }
 
-  ESP_LOGD(TAG, "Unregistering '%s' for universes %d-%d.", light_effect->get_name().c_str(),
-           light_effect->get_first_universe(), light_effect->get_last_universe());
+  ESP_LOGD(TAG, "Unregistering '%s' for universes %d-%d.", light_effect->get_name(), light_effect->get_first_universe(),
+           light_effect->get_last_universe());
 
   light_effects_.erase(light_effect);
 

esphome/components/e131/e131_addressable_light_effect.cpp

@@ -9,7 +9,7 @@ namespace e131 {
 static const char *const TAG = "e131_addressable_light_effect";
 static const int MAX_DATA_SIZE = (sizeof(E131Packet::values) - 1);
 
-E131AddressableLightEffect::E131AddressableLightEffect(const std::string &name) : AddressableLightEffect(name) {}
+E131AddressableLightEffect::E131AddressableLightEffect(const char *name) : AddressableLightEffect(name) {}
 
 int E131AddressableLightEffect::get_data_per_universe() const { return get_lights_per_universe() * channels_; }
 
@@ -58,8 +58,8 @@ bool E131AddressableLightEffect::process_(int universe, const E131Packet &packet
       std::min(it->size(), std::min(output_offset + get_lights_per_universe(), output_offset + packet.count - 1));
   auto *input_data = packet.values + 1;
 
-  ESP_LOGV(TAG, "Applying data for '%s' on %d universe, for %" PRId32 "-%d.", get_name().c_str(), universe,
-           output_offset, output_end);
+  ESP_LOGV(TAG, "Applying data for '%s' on %d universe, for %" PRId32 "-%d.", get_name(), universe, output_offset,
+           output_end);
 
   switch (channels_) {
     case E131_MONO:

esphome/components/e131/e131_addressable_light_effect.h

@@ -13,7 +13,7 @@ enum E131LightChannels { E131_MONO = 1, E131_RGB = 3, E131_RGBW = 4 };
 
 class E131AddressableLightEffect : public light::AddressableLightEffect {
  public:
-  E131AddressableLightEffect(const std::string &name);
+  E131AddressableLightEffect(const char *name);
 
   void start() override;
   void stop() override;

esphome/components/esp32/__init__.py

@@ -304,9 +304,13 @@ def _format_framework_arduino_version(ver: cv.Version) -> str:
 def _format_framework_espidf_version(ver: cv.Version, release: str) -> str:
     # format the given espidf (https://github.com/pioarduino/esp-idf/releases) version to
     # a PIO platformio/framework-espidf value
+    if ver == cv.Version(5, 4, 3) or ver >= cv.Version(5, 5, 1):
+        ext = "tar.xz"
+    else:
+        ext = "zip"
     if release:
-        return f"pioarduino/framework-espidf@https://github.com/pioarduino/esp-idf/releases/download/v{str(ver)}.{release}/esp-idf-v{str(ver)}.zip"
-    return f"pioarduino/framework-espidf@https://github.com/pioarduino/esp-idf/releases/download/v{str(ver)}/esp-idf-v{str(ver)}.zip"
+        return f"pioarduino/framework-espidf@https://github.com/pioarduino/esp-idf/releases/download/v{str(ver)}.{release}/esp-idf-v{str(ver)}.{ext}"
+    return f"pioarduino/framework-espidf@https://github.com/pioarduino/esp-idf/releases/download/v{str(ver)}/esp-idf-v{str(ver)}.{ext}"
 
 
 def _is_framework_url(source: str) -> str:
@@ -355,6 +359,7 @@ ESP_IDF_FRAMEWORK_VERSION_LOOKUP = {
 ESP_IDF_PLATFORM_VERSION_LOOKUP = {
     cv.Version(5, 5, 1): cv.Version(55, 3, 31, "1"),
     cv.Version(5, 5, 0): cv.Version(55, 3, 31, "1"),
+    cv.Version(5, 4, 3): cv.Version(55, 3, 32),
     cv.Version(5, 4, 2): cv.Version(54, 3, 21, "2"),
     cv.Version(5, 4, 1): cv.Version(54, 3, 21, "2"),
     cv.Version(5, 4, 0): cv.Version(54, 3, 21, "2"),
@@ -550,6 +555,32 @@ CONF_ENABLE_LWIP_BRIDGE_INTERFACE = "enable_lwip_bridge_interface"
 CONF_ENABLE_LWIP_TCPIP_CORE_LOCKING = "enable_lwip_tcpip_core_locking"
 CONF_ENABLE_LWIP_CHECK_THREAD_SAFETY = "enable_lwip_check_thread_safety"
 CONF_DISABLE_LIBC_LOCKS_IN_IRAM = "disable_libc_locks_in_iram"
+CONF_DISABLE_VFS_SUPPORT_TERMIOS = "disable_vfs_support_termios"
+CONF_DISABLE_VFS_SUPPORT_SELECT = "disable_vfs_support_select"
+CONF_DISABLE_VFS_SUPPORT_DIR = "disable_vfs_support_dir"
+
+# VFS requirement tracking
+# Components that need VFS features can call require_vfs_select() or require_vfs_dir()
+KEY_VFS_SELECT_REQUIRED = "vfs_select_required"
+KEY_VFS_DIR_REQUIRED = "vfs_dir_required"
+
+
+def require_vfs_select() -> None:
+    """Mark that VFS select support is required by a component.
+
+    Call this from components that use esp_vfs_eventfd or other VFS select features.
+    This prevents CONFIG_VFS_SUPPORT_SELECT from being disabled.
+    """
+    CORE.data[KEY_VFS_SELECT_REQUIRED] = True
+
+
+def require_vfs_dir() -> None:
+    """Mark that VFS directory support is required by a component.
+
+    Call this from components that use directory functions (opendir, readdir, mkdir, etc.).
+    This prevents CONFIG_VFS_SUPPORT_DIR from being disabled.
+    """
+    CORE.data[KEY_VFS_DIR_REQUIRED] = True
 
 
 def _validate_idf_component(config: ConfigType) -> ConfigType:
@@ -615,6 +646,13 @@ FRAMEWORK_SCHEMA = cv.All(
                     cv.Optional(
                         CONF_DISABLE_LIBC_LOCKS_IN_IRAM, default=True
                     ): cv.boolean,
+                    cv.Optional(
+                        CONF_DISABLE_VFS_SUPPORT_TERMIOS, default=True
+                    ): cv.boolean,
+                    cv.Optional(
+                        CONF_DISABLE_VFS_SUPPORT_SELECT, default=True
+                    ): cv.boolean,
+                    cv.Optional(CONF_DISABLE_VFS_SUPPORT_DIR, default=True): cv.boolean,
                     cv.Optional(CONF_EXECUTE_FROM_PSRAM): cv.boolean,
                 }
             ),
@@ -844,6 +882,11 @@ async def to_code(config):
     for clean_var in ("IDF_PATH", "IDF_TOOLS_PATH"):
         os.environ.pop(clean_var, None)
 
+    # Set the location of the IDF component manager cache
+    os.environ["IDF_COMPONENT_CACHE_PATH"] = str(
+        CORE.relative_internal_path(".espressif")
+    )
+
     add_extra_script(
         "post",
         "post_build.py",
@@ -962,6 +1005,43 @@ async def to_code(config):
     if advanced.get(CONF_DISABLE_LIBC_LOCKS_IN_IRAM, True):
         add_idf_sdkconfig_option("CONFIG_LIBC_LOCKS_PLACE_IN_IRAM", False)
 
+    # Disable VFS support for termios (terminal I/O functions)
+    # ESPHome doesn't use termios functions on ESP32 (only used in host UART driver).
+    # Saves approximately 1.8KB of flash when disabled (default).
+    add_idf_sdkconfig_option(
+        "CONFIG_VFS_SUPPORT_TERMIOS",
+        not advanced.get(CONF_DISABLE_VFS_SUPPORT_TERMIOS, True),
+    )
+
+    # Disable VFS support for select() with file descriptors
+    # ESPHome only uses select() with sockets via lwip_select(), which still works.
+    # VFS select is only needed for UART/eventfd file descriptors.
+    # Components that need it (e.g., openthread) call require_vfs_select().
+    # Saves approximately 2.7KB of flash when disabled (default).
+    if CORE.data.get(KEY_VFS_SELECT_REQUIRED, False):
+        # Component requires VFS select - force enable regardless of user setting
+        add_idf_sdkconfig_option("CONFIG_VFS_SUPPORT_SELECT", True)
+    else:
+        # No component needs it - allow user to control (default: disabled)
+        add_idf_sdkconfig_option(
+            "CONFIG_VFS_SUPPORT_SELECT",
+            not advanced.get(CONF_DISABLE_VFS_SUPPORT_SELECT, True),
+        )
+
+    # Disable VFS support for directory functions (opendir, readdir, mkdir, etc.)
+    # ESPHome doesn't use directory functions on ESP32.
+    # Components that need it (e.g., storage components) call require_vfs_dir().
+    # Saves approximately 0.5KB+ of flash when disabled (default).
+    if CORE.data.get(KEY_VFS_DIR_REQUIRED, False):
+        # Component requires VFS directory support - force enable regardless of user setting
+        add_idf_sdkconfig_option("CONFIG_VFS_SUPPORT_DIR", True)
+    else:
+        # No component needs it - allow user to control (default: disabled)
+        add_idf_sdkconfig_option(
+            "CONFIG_VFS_SUPPORT_DIR",
+            not advanced.get(CONF_DISABLE_VFS_SUPPORT_DIR, True),
+        )
+
     cg.add_platformio_option("board_build.partitions", "partitions.csv")
     if CONF_PARTITIONS in config:
         add_extra_build_file(

esphome/components/esp32/gpio.h

@@ -40,13 +40,13 @@ class ESP32InternalGPIOPin : public InternalGPIOPin {
   // - 3 bytes for members below
   // - 1 byte padding for alignment
   // - 4 bytes for vtable pointer
-  uint8_t pin_;        // GPIO pin number (0-255, actual max ~54 on ESP32)
-  gpio::Flags flags_;  // GPIO flags (1 byte)
+  uint8_t pin_;          // GPIO pin number (0-255, actual max ~54 on ESP32)
+  gpio::Flags flags_{};  // GPIO flags (1 byte)
   struct PinFlags {
     uint8_t inverted : 1;        // Invert pin logic (1 bit)
     uint8_t drive_strength : 2;  // Drive strength 0-3 (2 bits)
     uint8_t reserved : 5;        // Reserved for future use (5 bits)
-  } pin_flags_;                  // Total: 1 byte
+  } pin_flags_{};                // Total: 1 byte
   // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
   static bool isr_service_installed;
 };

esphome/components/esp32/gpio.py

@@ -223,7 +223,10 @@ async def esp32_pin_to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     num = config[CONF_NUMBER]
     cg.add(var.set_pin(getattr(gpio_num_t, f"GPIO_NUM_{num}")))
-    cg.add(var.set_inverted(config[CONF_INVERTED]))
+    # Only set if true to avoid bloating setup() function
+    # (inverted bit in pin_flags_ bitfield is zero-initialized to false)
+    if config[CONF_INVERTED]:
+        cg.add(var.set_inverted(True))
     if CONF_DRIVE_STRENGTH in config:
         cg.add(var.set_drive_strength(config[CONF_DRIVE_STRENGTH]))
     cg.add(var.set_flags(pins.gpio_flags_expr(config[CONF_MODE])))

esphome/components/esp32_ble_server/__init__.py

@@ -461,7 +461,9 @@ async def parse_value(value_config, args):
     if isinstance(value, str):
         value = list(value.encode(value_config[CONF_STRING_ENCODING]))
     if isinstance(value, list):
-        return cg.std_vector.template(cg.uint8)(value)
+        # Generate initializer list {1, 2, 3} instead of std::vector<uint8_t>({1, 2, 3})
+        # This calls the set_value(std::initializer_list<uint8_t>) overload
+        return cg.ArrayInitializer(*value)
     val = cg.RawExpression(f"{value_config[CONF_TYPE]}({cg.safe_exp(value)})")
     return ByteBuffer_ns.wrap(val, value_config[CONF_ENDIANNESS])
 

esphome/components/esp32_ble_server/ble_characteristic.cpp

@@ -35,13 +35,18 @@ BLECharacteristic::BLECharacteristic(const ESPBTUUID uuid, uint32_t properties)
 
 void BLECharacteristic::set_value(ByteBuffer buffer) { this->set_value(buffer.get_data()); }
 
-void BLECharacteristic::set_value(const std::vector<uint8_t> &buffer) {
+void BLECharacteristic::set_value(std::vector<uint8_t> &&buffer) {
   xSemaphoreTake(this->set_value_lock_, 0L);
-  this->value_ = buffer;
+  this->value_ = std::move(buffer);
   xSemaphoreGive(this->set_value_lock_);
 }
+
+void BLECharacteristic::set_value(std::initializer_list<uint8_t> data) {
+  this->set_value(std::vector<uint8_t>(data));  // Delegate to move overload
+}
+
 void BLECharacteristic::set_value(const std::string &buffer) {
-  this->set_value(std::vector<uint8_t>(buffer.begin(), buffer.end()));
+  this->set_value(std::vector<uint8_t>(buffer.begin(), buffer.end()));  // Delegate to move overload
 }
 
 void BLECharacteristic::notify() {

esphome/components/esp32_ble_server/ble_characteristic.h

@@ -33,7 +33,8 @@ class BLECharacteristic {
   ~BLECharacteristic();
 
   void set_value(ByteBuffer buffer);
-  void set_value(const std::vector<uint8_t> &buffer);
+  void set_value(std::vector<uint8_t> &&buffer);
+  void set_value(std::initializer_list<uint8_t> data);
   void set_value(const std::string &buffer);
 
   void set_broadcast_property(bool value);

esphome/components/esp32_ble_server/ble_descriptor.cpp

@@ -46,15 +46,17 @@ void BLEDescriptor::do_create(BLECharacteristic *characteristic) {
   this->state_ = CREATING;
 }
 
-void BLEDescriptor::set_value(std::vector<uint8_t> buffer) {
-  size_t length = buffer.size();
+void BLEDescriptor::set_value(std::vector<uint8_t> &&buffer) { this->set_value_impl_(buffer.data(), buffer.size()); }
 
+void BLEDescriptor::set_value(std::initializer_list<uint8_t> data) { this->set_value_impl_(data.begin(), data.size()); }
+
+void BLEDescriptor::set_value_impl_(const uint8_t *data, size_t length) {
   if (length > this->value_.attr_max_len) {
     ESP_LOGE(TAG, "Size %d too large, must be no bigger than %d", length, this->value_.attr_max_len);
     return;
   }
   this->value_.attr_len = length;
-  memcpy(this->value_.attr_value, buffer.data(), length);
+  memcpy(this->value_.attr_value, data, length);
 }
 
 void BLEDescriptor::gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if,

esphome/components/esp32_ble_server/ble_descriptor.h

@@ -27,7 +27,8 @@ class BLEDescriptor {
   void do_create(BLECharacteristic *characteristic);
   ESPBTUUID get_uuid() const { return this->uuid_; }
 
-  void set_value(std::vector<uint8_t> buffer);
+  void set_value(std::vector<uint8_t> &&buffer);
+  void set_value(std::initializer_list<uint8_t> data);
   void set_value(ByteBuffer buffer) { this->set_value(buffer.get_data()); }
 
   void gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);
@@ -42,6 +43,8 @@ class BLEDescriptor {
   }
 
  protected:
+  void set_value_impl_(const uint8_t *data, size_t length);
+
   BLECharacteristic *characteristic_{nullptr};
   ESPBTUUID uuid_;
   uint16_t handle_{0xFFFF};

esphome/components/esp32_improv/__init__.py

@@ -112,7 +112,7 @@ async def to_code(config):
 
     cg.add_define("USE_IMPROV")
 
-    await improv_base.setup_improv_core(var, config)
+    await improv_base.setup_improv_core(var, config, "esp32_improv")
 
     cg.add(var.set_identify_duration(config[CONF_IDENTIFY_DURATION]))
     cg.add(var.set_authorized_duration(config[CONF_AUTHORIZED_DURATION]))

esphome/components/esp32_improv/esp32_improv_component.cpp

@@ -270,8 +270,8 @@ void ESP32ImprovComponent::set_error_(improv::Error error) {
   }
 }
 
-void ESP32ImprovComponent::send_response_(std::vector<uint8_t> &response) {
-  this->rpc_response_->set_value(ByteBuffer::wrap(response));
+void ESP32ImprovComponent::send_response_(std::vector<uint8_t> &&response) {
+  this->rpc_response_->set_value(std::move(response));
   if (this->state_ != improv::STATE_STOPPED)
     this->rpc_response_->notify();
 }
@@ -389,11 +389,13 @@ void ESP32ImprovComponent::check_wifi_connection_() {
     std::string url_strings[3];
     size_t url_count = 0;
 
+#ifdef USE_ESP32_IMPROV_NEXT_URL
     // Add next_url if configured (should be first per Improv BLE spec)
     std::string next_url = this->get_formatted_next_url_();
     if (!next_url.empty()) {
       url_strings[url_count++] = std::move(next_url);
     }
+#endif
 
     // Add default URLs for backward compatibility
     url_strings[url_count++] = ESPHOME_MY_LINK;
@@ -407,10 +409,8 @@ void ESP32ImprovComponent::check_wifi_connection_() {
       }
     }
 #endif
-    // Pass to build_rpc_response using vector constructor from iterators to avoid extra copies
-    std::vector<uint8_t> data = improv::build_rpc_response(
-        improv::WIFI_SETTINGS, std::vector<std::string>(url_strings, url_strings + url_count));
-    this->send_response_(data);
+    this->send_response_(improv::build_rpc_response(improv::WIFI_SETTINGS,
+                                                    std::vector<std::string>(url_strings, url_strings + url_count)));
   } else if (this->is_active() && this->state_ != improv::STATE_PROVISIONED) {
     ESP_LOGD(TAG, "WiFi provisioned externally");
   }

esphome/components/esp32_improv/esp32_improv_component.h

@@ -109,7 +109,7 @@ class ESP32ImprovComponent : public Component, public improv_base::ImprovBase {
   void set_state_(improv::State state, bool update_advertising = true);
   void set_error_(improv::Error error);
   improv::State get_initial_state_() const;
-  void send_response_(std::vector<uint8_t> &response);
+  void send_response_(std::vector<uint8_t> &&response);
   void process_incoming_data_();
   void on_wifi_connect_timeout_();
   void check_wifi_connection_();

esphome/components/esp8266/__init__.py

@@ -190,7 +190,9 @@ async def to_code(config):
     cg.add_define("ESPHOME_VARIANT", "ESP8266")
     cg.add_define(ThreadModel.SINGLE)
 
-    cg.add_platformio_option("extra_scripts", ["pre:iram_fix.py", "post:post_build.py"])
+    cg.add_platformio_option(
+        "extra_scripts", ["pre:testing_mode.py", "post:post_build.py"]
+    )
 
     conf = config[CONF_FRAMEWORK]
     cg.add_platformio_option("framework", "arduino")
@@ -230,9 +232,9 @@ async def to_code(config):
     # For cases where nullptrs can be handled, use nothrow: `new (std::nothrow) T;`
     cg.add_build_flag("-DNEW_OOM_ABORT")
 
-    # In testing mode, fake a larger IRAM to allow linking grouped component tests
-    # Real ESP8266 hardware only has 32KB IRAM, but for CI testing we pretend it has 2MB
-    # This is done via a pre-build script that generates a custom linker script
+    # In testing mode, fake larger memory to allow linking grouped component tests
+    # Real ESP8266 hardware only has 32KB IRAM and ~80KB RAM, but for CI testing
+    # we pretend it has much larger memory to test that components compile together
     if CORE.testing_mode:
         cg.add_build_flag("-DESPHOME_TESTING_MODE")
 
@@ -271,8 +273,8 @@ def copy_files():
         post_build_file,
         CORE.relative_build_path("post_build.py"),
     )
-    iram_fix_file = dir / "iram_fix.py.script"
+    testing_mode_file = dir / "testing_mode.py.script"
     copy_file_if_changed(
-        iram_fix_file,
-        CORE.relative_build_path("iram_fix.py"),
+        testing_mode_file,
+        CORE.relative_build_path("testing_mode.py"),
     )

esphome/components/esp8266/gpio.h

@@ -29,8 +29,8 @@ class ESP8266GPIOPin : public InternalGPIOPin {
   void attach_interrupt(void (*func)(void *), void *arg, gpio::InterruptType type) const override;
 
   uint8_t pin_;
-  bool inverted_;
-  gpio::Flags flags_;
+  bool inverted_{};
+  gpio::Flags flags_{};
 };
 
 }  // namespace esp8266

esphome/components/esp8266/gpio.py

@@ -165,7 +165,10 @@ async def esp8266_pin_to_code(config):
     num = config[CONF_NUMBER]
     mode = config[CONF_MODE]
     cg.add(var.set_pin(num))
-    cg.add(var.set_inverted(config[CONF_INVERTED]))
+    # Only set if true to avoid bloating setup() function
+    # (inverted bit in pin_flags_ bitfield is zero-initialized to false)
+    if config[CONF_INVERTED]:
+        cg.add(var.set_inverted(True))
     cg.add(var.set_flags(pins.gpio_flags_expr(mode)))
     if num < 16:
         initial_state: PinInitialState = CORE.data[KEY_ESP8266][KEY_PIN_INITIAL_STATES][

esphome/components/esp8266/iram_fix.py.script

@@ -1,44 +0,0 @@
-import os
-import re
-
-# pylint: disable=E0602
-Import("env")  # noqa
-
-
-def patch_linker_script_after_preprocess(source, target, env):
-    """Patch the local linker script after PlatformIO preprocesses it."""
-    # Check if we're in testing mode by looking for the define
-    build_flags = env.get("BUILD_FLAGS", [])
-    testing_mode = any("-DESPHOME_TESTING_MODE" in flag for flag in build_flags)
-
-    if not testing_mode:
-        return
-
-    # Get the local linker script path
-    build_dir = env.subst("$BUILD_DIR")
-    local_ld = os.path.join(build_dir, "ld", "local.eagle.app.v6.common.ld")
-
-    if not os.path.exists(local_ld):
-        return
-
-    # Read the linker script
-    with open(local_ld, "r") as f:
-        content = f.read()
-
-    # Replace IRAM size from 0x8000 (32KB) to 0x200000 (2MB)
-    # The line looks like: iram1_0_seg : org = 0x40100000, len = 0x8000
-    updated = re.sub(
-        r"(iram1_0_seg\s*:\s*org\s*=\s*0x40100000\s*,\s*len\s*=\s*)0x8000",
-        r"\g<1>0x200000",
-        content,
-    )
-
-    if updated != content:
-        with open(local_ld, "w") as f:
-            f.write(updated)
-        print("ESPHome: Patched IRAM size to 2MB for testing mode")
-
-
-# Hook into the build process right before linking
-# This runs after PlatformIO has already preprocessed the linker scripts
-env.AddPreAction("$BUILD_DIR/${PROGNAME}.elf", patch_linker_script_after_preprocess)

esphome/components/esp8266/testing_mode.py.script

@@ -0,0 +1,166 @@
+import os
+import re
+
+# pylint: disable=E0602
+Import("env")  # noqa
+
+
+# Memory sizes for testing mode (allow larger builds for CI component grouping)
+TESTING_IRAM_SIZE = "0x200000"  # 2MB
+TESTING_DRAM_SIZE = "0x200000"  # 2MB
+TESTING_FLASH_SIZE = "0x2000000"  # 32MB
+
+
+def patch_segment_size(content, segment_name, new_size, label):
+    """Patch a memory segment's length in linker script.
+
+    Args:
+        content: Linker script content
+        segment_name: Name of the segment (e.g., 'iram1_0_seg')
+        new_size: New size as hex string (e.g., '0x200000')
+        label: Human-readable label for logging (e.g., 'IRAM')
+
+    Returns:
+        Tuple of (patched_content, was_patched)
+    """
+    # Match: segment_name : org = 0x..., len = 0x...
+    pattern = rf"({segment_name}\s*:\s*org\s*=\s*0x[0-9a-fA-F]+\s*,\s*len\s*=\s*)0x[0-9a-fA-F]+"
+    new_content = re.sub(pattern, rf"\g<1>{new_size}", content)
+    return new_content, new_content != content
+
+
+def apply_memory_patches(content):
+    """Apply IRAM, DRAM, and Flash patches to linker script content.
+
+    Args:
+        content: Linker script content as string
+
+    Returns:
+        Patched content as string
+    """
+    patches_applied = []
+
+    # Patch IRAM (for larger code in IRAM)
+    content, patched = patch_segment_size(content, "iram1_0_seg", TESTING_IRAM_SIZE, "IRAM")
+    if patched:
+        patches_applied.append("IRAM")
+
+    # Patch DRAM (for larger BSS/data sections)
+    content, patched = patch_segment_size(content, "dram0_0_seg", TESTING_DRAM_SIZE, "DRAM")
+    if patched:
+        patches_applied.append("DRAM")
+
+    # Patch Flash (for larger code sections)
+    content, patched = patch_segment_size(content, "irom0_0_seg", TESTING_FLASH_SIZE, "Flash")
+    if patched:
+        patches_applied.append("Flash")
+
+    if patches_applied:
+        iram_mb = int(TESTING_IRAM_SIZE, 16) // (1024 * 1024)
+        dram_mb = int(TESTING_DRAM_SIZE, 16) // (1024 * 1024)
+        flash_mb = int(TESTING_FLASH_SIZE, 16) // (1024 * 1024)
+        print(f"  Patched memory segments: {', '.join(patches_applied)} (IRAM/DRAM: {iram_mb}MB, Flash: {flash_mb}MB)")
+
+    return content
+
+
+def patch_linker_script_file(filepath, description):
+    """Patch a linker script file in the build directory with enlarged memory segments.
+
+    This function modifies linker scripts in the build directory only (never SDK files).
+    It patches IRAM, DRAM, and Flash segments to allow larger builds in testing mode.
+
+    Args:
+        filepath: Path to the linker script file in the build directory
+        description: Human-readable description for logging
+
+    Returns:
+        True if the file was patched, False if already patched or not found
+    """
+    if not os.path.exists(filepath):
+        print(f"ESPHome: {description} not found at {filepath}")
+        return False
+
+    print(f"ESPHome: Patching {description}...")
+    with open(filepath, "r") as f:
+        content = f.read()
+
+    patched_content = apply_memory_patches(content)
+
+    if patched_content != content:
+        with open(filepath, "w") as f:
+            f.write(patched_content)
+        print(f"ESPHome: Successfully patched {description}")
+        return True
+    else:
+        print(f"ESPHome: {description} already patched or no changes needed")
+        return False
+
+
+def patch_local_linker_script(source, target, env):
+    """Patch the local.eagle.app.v6.common.ld in build directory.
+
+    This patches the preprocessed linker script that PlatformIO creates in the build
+    directory, enlarging IRAM, DRAM, and Flash segments for testing mode.
+
+    Args:
+        source: SCons source nodes
+        target: SCons target nodes
+        env: SCons environment
+    """
+    # Check if we're in testing mode
+    build_flags = env.get("BUILD_FLAGS", [])
+    testing_mode = any("-DESPHOME_TESTING_MODE" in flag for flag in build_flags)
+
+    if not testing_mode:
+        return
+
+    # Patch the local linker script if it exists
+    build_dir = env.subst("$BUILD_DIR")
+    ld_dir = os.path.join(build_dir, "ld")
+    if os.path.exists(ld_dir):
+        local_ld = os.path.join(ld_dir, "local.eagle.app.v6.common.ld")
+        if os.path.exists(local_ld):
+            patch_linker_script_file(local_ld, "local.eagle.app.v6.common.ld")
+
+
+# Check if we're in testing mode
+build_flags = env.get("BUILD_FLAGS", [])
+testing_mode = any("-DESPHOME_TESTING_MODE" in flag for flag in build_flags)
+
+if testing_mode:
+    # Create a custom linker script in the build directory with patched memory limits
+    # This allows larger IRAM/DRAM/Flash for CI component grouping tests
+    build_dir = env.subst("$BUILD_DIR")
+    ldscript = env.GetProjectOption("board_build.ldscript", "")
+    assert ldscript, "No linker script configured in board_build.ldscript"
+
+    framework_dir = env.PioPlatform().get_package_dir("framework-arduinoespressif8266")
+    assert framework_dir is not None, "Could not find framework-arduinoespressif8266 package"
+
+    # Read the original SDK linker script (read-only, SDK is never modified)
+    sdk_ld = os.path.join(framework_dir, "tools", "sdk", "ld", ldscript)
+    # Create a custom version in the build directory (isolated, temporary)
+    custom_ld = os.path.join(build_dir, f"testing_{ldscript}")
+
+    if os.path.exists(sdk_ld) and not os.path.exists(custom_ld):
+        # Read the SDK linker script
+        with open(sdk_ld, "r") as f:
+            content = f.read()
+
+        # Apply memory patches (IRAM: 2MB, DRAM: 2MB, Flash: 32MB)
+        patched_content = apply_memory_patches(content)
+
+        # Write the patched linker script to the build directory
+        with open(custom_ld, "w") as f:
+            f.write(patched_content)
+
+        print(f"ESPHome: Created custom linker script: {custom_ld}")
+
+    # Tell the linker to use our custom script from the build directory
+    assert os.path.exists(custom_ld), f"Custom linker script not found: {custom_ld}"
+    env.Replace(LDSCRIPT_PATH=custom_ld)
+    print(f"ESPHome: Using custom linker script with patched memory limits")
+
+    # Also patch local.eagle.app.v6.common.ld after PlatformIO creates it
+    env.AddPreAction("$BUILD_DIR/${PROGNAME}.elf", patch_local_linker_script)

esphome/components/esphome/ota/ota_esphome.cpp

@@ -281,19 +281,15 @@ void ESPHomeOTAComponent::handle_data_() {
 #endif
 
   // Acknowledge auth OK - 1 byte
-  buf[0] = ota::OTA_RESPONSE_AUTH_OK;
-  this->writeall_(buf, 1);
+  this->write_byte_(ota::OTA_RESPONSE_AUTH_OK);
 
   // Read size, 4 bytes MSB first
   if (!this->readall_(buf, 4)) {
     this->log_read_error_(LOG_STR("size"));
     goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
   }
-  ota_size = 0;
-  for (uint8_t i = 0; i < 4; i++) {
-    ota_size <<= 8;
-    ota_size |= buf[i];
-  }
+  ota_size = (static_cast<size_t>(buf[0]) << 24) | (static_cast<size_t>(buf[1]) << 16) |
+             (static_cast<size_t>(buf[2]) << 8) | buf[3];
   ESP_LOGV(TAG, "Size is %u bytes", ota_size);
 
   // Now that we've passed authentication and are actually
@@ -313,8 +309,7 @@ void ESPHomeOTAComponent::handle_data_() {
   update_started = true;
 
   // Acknowledge prepare OK - 1 byte
-  buf[0] = ota::OTA_RESPONSE_UPDATE_PREPARE_OK;
-  this->writeall_(buf, 1);
+  this->write_byte_(ota::OTA_RESPONSE_UPDATE_PREPARE_OK);
 
   // Read binary MD5, 32 bytes
   if (!this->readall_(buf, 32)) {
@@ -326,8 +321,7 @@ void ESPHomeOTAComponent::handle_data_() {
   this->backend_->set_update_md5(sbuf);
 
   // Acknowledge MD5 OK - 1 byte
-  buf[0] = ota::OTA_RESPONSE_BIN_MD5_OK;
-  this->writeall_(buf, 1);
+  this->write_byte_(ota::OTA_RESPONSE_BIN_MD5_OK);
 
   while (total < ota_size) {
     // TODO: timeout check
@@ -354,8 +348,7 @@ void ESPHomeOTAComponent::handle_data_() {
     total += read;
 #if USE_OTA_VERSION == 2
     while (size_acknowledged + OTA_BLOCK_SIZE <= total || (total == ota_size && size_acknowledged < ota_size)) {
-      buf[0] = ota::OTA_RESPONSE_CHUNK_OK;
-      this->writeall_(buf, 1);
+      this->write_byte_(ota::OTA_RESPONSE_CHUNK_OK);
       size_acknowledged += OTA_BLOCK_SIZE;
     }
 #endif
@@ -374,8 +367,7 @@ void ESPHomeOTAComponent::handle_data_() {
   }
 
   // Acknowledge receive OK - 1 byte
-  buf[0] = ota::OTA_RESPONSE_RECEIVE_OK;
-  this->writeall_(buf, 1);
+  this->write_byte_(ota::OTA_RESPONSE_RECEIVE_OK);
 
   error_code = this->backend_->end();
   if (error_code != ota::OTA_RESPONSE_OK) {
@@ -384,8 +376,7 @@ void ESPHomeOTAComponent::handle_data_() {
   }
 
   // Acknowledge Update end OK - 1 byte
-  buf[0] = ota::OTA_RESPONSE_UPDATE_END_OK;
-  this->writeall_(buf, 1);
+  this->write_byte_(ota::OTA_RESPONSE_UPDATE_END_OK);
 
   // Read ACK
   if (!this->readall_(buf, 1) || buf[0] != ota::OTA_RESPONSE_OK) {
@@ -404,8 +395,7 @@ void ESPHomeOTAComponent::handle_data_() {
   App.safe_reboot();
 
 error:
-  buf[0] = static_cast<uint8_t>(error_code);
-  this->writeall_(buf, 1);
+  this->write_byte_(static_cast<uint8_t>(error_code));
   this->cleanup_connection_();
 
   if (this->backend_ != nullptr && update_started) {

esphome/components/esphome/ota/ota_esphome.h

@@ -53,6 +53,7 @@ class ESPHomeOTAComponent : public ota::OTAComponent {
 #endif  // USE_OTA_PASSWORD
   bool readall_(uint8_t *buf, size_t len);
   bool writeall_(const uint8_t *buf, size_t len);
+  inline bool write_byte_(uint8_t byte) { return this->writeall_(&byte, 1); }
 
   bool try_read_(size_t to_read, const LogString *desc);
   bool try_write_(size_t to_write, const LogString *desc);

esphome/components/espnow/automation.h

@@ -14,13 +14,13 @@ template<typename... Ts> class SendAction : public Action<Ts...>, public Parente
   TEMPLATABLE_VALUE(std::vector<uint8_t>, data);
 
  public:
-  void add_on_sent(const std::vector<Action<Ts...> *> &actions) {
+  void add_on_sent(const std::initializer_list<Action<Ts...> *> &actions) {
     this->sent_.add_actions(actions);
     if (this->flags_.wait_for_sent) {
       this->sent_.add_action(new LambdaAction<Ts...>([this](Ts... x) { this->play_next_(x...); }));
     }
   }
-  void add_on_error(const std::vector<Action<Ts...> *> &actions) {
+  void add_on_error(const std::initializer_list<Action<Ts...> *> &actions) {
     this->error_.add_actions(actions);
     if (this->flags_.wait_for_sent) {
       this->error_.add_action(new LambdaAction<Ts...>([this](Ts... x) {

esphome/components/ethernet/__init__.py

@@ -14,7 +14,7 @@ from esphome.components.esp32.const import (
     VARIANT_ESP32S2,
     VARIANT_ESP32S3,
 )
-from esphome.components.network import IPAddress
+from esphome.components.network import ip_address_literal
 from esphome.components.spi import CONF_INTERFACE_INDEX, get_spi_interface
 import esphome.config_validation as cv
 from esphome.const import (
@@ -32,6 +32,7 @@ from esphome.const import (
     CONF_MISO_PIN,
     CONF_MODE,
     CONF_MOSI_PIN,
+    CONF_NUMBER,
     CONF_PAGE_ID,
     CONF_PIN,
     CONF_POLLING_INTERVAL,
@@ -52,12 +53,36 @@ from esphome.core import (
     coroutine_with_priority,
 )
 import esphome.final_validate as fv
+from esphome.types import ConfigType
 
 CONFLICTS_WITH = ["wifi"]
 DEPENDENCIES = ["esp32"]
 AUTO_LOAD = ["network"]
 LOGGER = logging.getLogger(__name__)
 
+# RMII pins that are hardcoded on ESP32 classic and cannot be changed
+# These pins are used by the internal Ethernet MAC when using RMII PHYs
+ESP32_RMII_FIXED_PINS = {
+    19: "EMAC_TXD0",
+    21: "EMAC_TX_EN",
+    22: "EMAC_TXD1",
+    25: "EMAC_RXD0",
+    26: "EMAC_RXD1",
+    27: "EMAC_RX_CRS_DV",
+}
+
+# RMII default pins for ESP32-P4
+# These are the default pins used by ESP-IDF and are configurable in principle,
+# but ESPHome's ethernet component currently has no way to change them
+ESP32P4_RMII_DEFAULT_PINS = {
+    34: "EMAC_TXD0",
+    35: "EMAC_TXD1",
+    28: "EMAC_RX_CRS_DV",
+    29: "EMAC_RXD0",
+    30: "EMAC_RXD1",
+    49: "EMAC_TX_EN",
+}
+
 ethernet_ns = cg.esphome_ns.namespace("ethernet")
 PHYRegister = ethernet_ns.struct("PHYRegister")
 CONF_PHY_ADDR = "phy_addr"
@@ -273,7 +298,7 @@ CONFIG_SCHEMA = cv.All(
 )
 
 
-def _final_validate(config):
+def _final_validate_spi(config):
     if config[CONF_TYPE] not in SPI_ETHERNET_TYPES:
         return
     if spi_configs := fv.full_config.get().get(CONF_SPI):
@@ -292,17 +317,14 @@ def _final_validate(config):
                     )
 
 
-FINAL_VALIDATE_SCHEMA = _final_validate
-
-
 def manual_ip(config):
     return cg.StructInitializer(
         ManualIP,
-        ("static_ip", IPAddress(str(config[CONF_STATIC_IP]))),
-        ("gateway", IPAddress(str(config[CONF_GATEWAY]))),
-        ("subnet", IPAddress(str(config[CONF_SUBNET]))),
-        ("dns1", IPAddress(str(config[CONF_DNS1]))),
-        ("dns2", IPAddress(str(config[CONF_DNS2]))),
+        ("static_ip", ip_address_literal(config[CONF_STATIC_IP])),
+        ("gateway", ip_address_literal(config[CONF_GATEWAY])),
+        ("subnet", ip_address_literal(config[CONF_SUBNET])),
+        ("dns1", ip_address_literal(config[CONF_DNS1])),
+        ("dns2", ip_address_literal(config[CONF_DNS2])),
     )
 
 
@@ -383,3 +405,57 @@ async def to_code(config):
 
     if CORE.using_arduino:
         cg.add_library("WiFi", None)
+
+
+def _final_validate_rmii_pins(config: ConfigType) -> None:
+    """Validate that RMII pins are not used by other components."""
+    # Only validate for RMII-based PHYs on ESP32/ESP32P4
+    if config[CONF_TYPE] in SPI_ETHERNET_TYPES or config[CONF_TYPE] == "OPENETH":
+        return  # SPI and OPENETH don't use RMII
+
+    variant = get_esp32_variant()
+    if variant == VARIANT_ESP32:
+        rmii_pins = ESP32_RMII_FIXED_PINS
+        is_configurable = False
+    elif variant == VARIANT_ESP32P4:
+        rmii_pins = ESP32P4_RMII_DEFAULT_PINS
+        is_configurable = True
+    else:
+        return  # No RMII validation needed for other variants
+
+    # Check all used pins against RMII reserved pins
+    for pin_list in pins.PIN_SCHEMA_REGISTRY.pins_used.values():
+        for pin_path, _, pin_config in pin_list:
+            pin_num = pin_config.get(CONF_NUMBER)
+            if pin_num not in rmii_pins:
+                continue
+            # Found a conflict - show helpful error message
+            pin_function = rmii_pins[pin_num]
+            component_path = ".".join(str(p) for p in pin_path)
+            if is_configurable:
+                error_msg = (
+                    f"GPIO{pin_num} is used by Ethernet RMII "
+                    f"({pin_function}) with the current default "
+                    f"configuration. This conflicts with '{component_path}'. "
+                    f"Please choose a different GPIO pin for "
+                    f"'{component_path}'."
+                )
+            else:
+                error_msg = (
+                    f"GPIO{pin_num} is reserved for Ethernet RMII "
+                    f"({pin_function}) and cannot be used. This pin is "
+                    f"hardcoded by ESP-IDF and cannot be changed when using "
+                    f"RMII Ethernet PHYs. Please choose a different GPIO pin "
+                    f"for '{component_path}'."
+                )
+            raise cv.Invalid(error_msg, path=pin_path)
+
+
+def _final_validate(config: ConfigType) -> ConfigType:
+    """Final validation for Ethernet component."""
+    _final_validate_spi(config)
+    _final_validate_rmii_pins(config)
+    return config
+
+
+FINAL_VALIDATE_SCHEMA = _final_validate

esphome/components/event/event.cpp

@@ -8,12 +8,19 @@ namespace event {
 static const char *const TAG = "event";
 
 void Event::trigger(const std::string &event_type) {
-  auto found = types_.find(event_type);
-  if (found == types_.end()) {
+  // Linear search - faster than std::set for small datasets (1-5 items typical)
+  const std::string *found = nullptr;
+  for (const auto &type : this->types_) {
+    if (type == event_type) {
+      found = &type;
+      break;
+    }
+  }
+  if (found == nullptr) {
     ESP_LOGE(TAG, "'%s': invalid event type for trigger(): %s", this->get_name().c_str(), event_type.c_str());
     return;
   }
-  last_event_type = &(*found);
+  last_event_type = found;
   ESP_LOGD(TAG, "'%s' Triggered event '%s'", this->get_name().c_str(), last_event_type->c_str());
   this->event_callback_.call(event_type);
 }

esphome/components/event/event.h

@@ -1,6 +1,5 @@
 #pragma once
 
-#include <set>
 #include <string>
 
 #include "esphome/core/component.h"
@@ -26,13 +25,13 @@ class Event : public EntityBase, public EntityBase_DeviceClass {
   const std::string *last_event_type;
 
   void trigger(const std::string &event_type);
-  void set_event_types(const std::set<std::string> &event_types) { this->types_ = event_types; }
-  std::set<std::string> get_event_types() const { return this->types_; }
+  void set_event_types(const std::initializer_list<std::string> &event_types) { this->types_ = event_types; }
+  const FixedVector<std::string> &get_event_types() const { return this->types_; }
   void add_on_event_callback(std::function<void(const std::string &event_type)> &&callback);
 
  protected:
   CallbackManager<void(const std::string &event_type)> event_callback_;
-  std::set<std::string> types_;
+  FixedVector<std::string> types_;
 };
 
 }  // namespace event

esphome/components/fan/fan.h

@@ -60,8 +60,6 @@ class FanCall {
     this->speed_ = speed;
     return *this;
   }
-  ESPDEPRECATED("set_speed() with string argument is deprecated, use integer argument instead.", "2021.9")
-  FanCall &set_speed(const char *legacy_speed);
   optional<int> get_speed() const { return this->speed_; }
   FanCall &set_direction(FanDirection direction) {
     this->direction_ = direction;

esphome/components/gpio/switch/gpio_switch.cpp

@@ -67,7 +67,7 @@ void GPIOSwitch::write_state(bool state) {
   this->pin_->digital_write(state);
   this->publish_state(state);
 }
-void GPIOSwitch::set_interlock(const std::vector<Switch *> &interlock) { this->interlock_ = interlock; }
+void GPIOSwitch::set_interlock(const std::initializer_list<Switch *> &interlock) { this->interlock_ = interlock; }
 
 }  // namespace gpio
 }  // namespace esphome

esphome/components/gpio/switch/gpio_switch.h

@@ -2,10 +2,9 @@
 
 #include "esphome/core/component.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
 #include "esphome/components/switch/switch.h"
 
-#include <vector>
-
 namespace esphome {
 namespace gpio {
 
@@ -19,14 +18,14 @@ class GPIOSwitch : public switch_::Switch, public Component {
 
   void setup() override;
   void dump_config() override;
-  void set_interlock(const std::vector<Switch *> &interlock);
+  void set_interlock(const std::initializer_list<Switch *> &interlock);
   void set_interlock_wait_time(uint32_t interlock_wait_time) { interlock_wait_time_ = interlock_wait_time; }
 
  protected:
   void write_state(bool state) override;
 
   GPIOPin *pin_;
-  std::vector<Switch *> interlock_;
+  FixedVector<Switch *> interlock_;
   uint32_t interlock_wait_time_{0};
 };
 

esphome/components/haier/haier_base.cpp

@@ -171,7 +171,7 @@ void HaierClimateBase::toggle_power() {
       PendingAction({ActionRequest::TOGGLE_POWER, esphome::optional<haier_protocol::HaierMessage>()});
 }
 
-void HaierClimateBase::set_supported_swing_modes(const std::set<climate::ClimateSwingMode> &modes) {
+void HaierClimateBase::set_supported_swing_modes(climate::ClimateSwingModeMask modes) {
   this->traits_.set_supported_swing_modes(modes);
   if (!modes.empty())
     this->traits_.add_supported_swing_mode(climate::CLIMATE_SWING_OFF);
@@ -179,13 +179,13 @@ void HaierClimateBase::set_supported_swing_modes(const std::set<climate::Climate
 
 void HaierClimateBase::set_answer_timeout(uint32_t timeout) { this->haier_protocol_.set_answer_timeout(timeout); }
 
-void HaierClimateBase::set_supported_modes(const std::set<climate::ClimateMode> &modes) {
+void HaierClimateBase::set_supported_modes(climate::ClimateModeMask modes) {
   this->traits_.set_supported_modes(modes);
   this->traits_.add_supported_mode(climate::CLIMATE_MODE_OFF);        // Always available
   this->traits_.add_supported_mode(climate::CLIMATE_MODE_HEAT_COOL);  // Always available
 }
 
-void HaierClimateBase::set_supported_presets(const std::set<climate::ClimatePreset> &presets) {
+void HaierClimateBase::set_supported_presets(climate::ClimatePresetMask presets) {
   this->traits_.set_supported_presets(presets);
   if (!presets.empty())
     this->traits_.add_supported_preset(climate::CLIMATE_PRESET_NONE);

esphome/components/haier/haier_base.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <chrono>
-#include <set>
 #include "esphome/components/climate/climate.h"
 #include "esphome/components/uart/uart.h"
 #include "esphome/core/automation.h"
@@ -60,9 +59,9 @@ class HaierClimateBase : public esphome::Component,
   void send_power_off_command();
   void toggle_power();
   void reset_protocol() { this->reset_protocol_request_ = true; };
-  void set_supported_modes(const std::set<esphome::climate::ClimateMode> &modes);
-  void set_supported_swing_modes(const std::set<esphome::climate::ClimateSwingMode> &modes);
-  void set_supported_presets(const std::set<esphome::climate::ClimatePreset> &presets);
+  void set_supported_modes(esphome::climate::ClimateModeMask modes);
+  void set_supported_swing_modes(esphome::climate::ClimateSwingModeMask modes);
+  void set_supported_presets(esphome::climate::ClimatePresetMask presets);
   bool valid_connection() const { return this->protocol_phase_ >= ProtocolPhases::IDLE; };
   size_t available() noexcept override { return esphome::uart::UARTDevice::available(); };
   size_t read_array(uint8_t *data, size_t len) noexcept override {

esphome/components/haier/hon_climate.cpp

@@ -1033,9 +1033,9 @@ haier_protocol::HandlerError HonClimate::process_status_message_(const uint8_t *
   {
     // Swing mode
     ClimateSwingMode old_swing_mode = this->swing_mode;
-    const std::set<ClimateSwingMode> &swing_modes = traits_.get_supported_swing_modes();
-    bool vertical_swing_supported = swing_modes.find(CLIMATE_SWING_VERTICAL) != swing_modes.end();
-    bool horizontal_swing_supported = swing_modes.find(CLIMATE_SWING_HORIZONTAL) != swing_modes.end();
+    const auto &swing_modes = traits_.get_supported_swing_modes();
+    bool vertical_swing_supported = swing_modes.count(CLIMATE_SWING_VERTICAL);
+    bool horizontal_swing_supported = swing_modes.count(CLIMATE_SWING_HORIZONTAL);
     if (horizontal_swing_supported &&
         (packet.control.horizontal_swing_mode == (uint8_t) hon_protocol::HorizontalSwingMode::AUTO)) {
       if (vertical_swing_supported &&
@@ -1218,13 +1218,13 @@ void HonClimate::fill_control_messages_queue_() {
                                                 (uint8_t) hon_protocol::DataParameters::QUIET_MODE,
                                             quiet_mode_buf, 2);
     }
-    if ((fast_mode_buf[1] != 0xFF) && ((presets.find(climate::ClimatePreset::CLIMATE_PRESET_BOOST) != presets.end()))) {
+    if ((fast_mode_buf[1] != 0xFF) && presets.count(climate::ClimatePreset::CLIMATE_PRESET_BOOST)) {
       this->control_messages_queue_.emplace(haier_protocol::FrameType::CONTROL,
                                             (uint16_t) hon_protocol::SubcommandsControl::SET_SINGLE_PARAMETER +
                                                 (uint8_t) hon_protocol::DataParameters::FAST_MODE,
                                             fast_mode_buf, 2);
     }
-    if ((away_mode_buf[1] != 0xFF) && ((presets.find(climate::ClimatePreset::CLIMATE_PRESET_AWAY) != presets.end()))) {
+    if ((away_mode_buf[1] != 0xFF) && presets.count(climate::ClimatePreset::CLIMATE_PRESET_AWAY)) {
       this->control_messages_queue_.emplace(haier_protocol::FrameType::CONTROL,
                                             (uint16_t) hon_protocol::SubcommandsControl::SET_SINGLE_PARAMETER +
                                                 (uint8_t) hon_protocol::DataParameters::TEN_DEGREE,

esphome/components/hdc2010/__init__.py

@@ -0,0 +1 @@
+CODEOWNERS = ["@optimusprimespace", "@ssieb"]

esphome/components/hdc2010/hdc2010.cpp

@@ -0,0 +1,111 @@
+#include "esphome/core/hal.h"
+#include "hdc2010.h"
+// https://github.com/vigsterkr/homebridge-hdc2010/blob/main/src/hdc2010.js
+// https://github.com/lime-labs/HDC2080-Arduino/blob/master/src/HDC2080.cpp
+namespace esphome {
+namespace hdc2010 {
+
+static const char *const TAG = "hdc2010";
+
+static const uint8_t HDC2010_ADDRESS = 0x40;  // 0b1000000 or 0b1000001 from datasheet
+static const uint8_t HDC2010_CMD_CONFIGURATION_MEASUREMENT = 0x8F;
+static const uint8_t HDC2010_CMD_START_MEASUREMENT = 0xF9;
+static const uint8_t HDC2010_CMD_TEMPERATURE_LOW = 0x00;
+static const uint8_t HDC2010_CMD_TEMPERATURE_HIGH = 0x01;
+static const uint8_t HDC2010_CMD_HUMIDITY_LOW = 0x02;
+static const uint8_t HDC2010_CMD_HUMIDITY_HIGH = 0x03;
+static const uint8_t CONFIG = 0x0E;
+static const uint8_t MEASUREMENT_CONFIG = 0x0F;
+
+void HDC2010Component::setup() {
+  ESP_LOGCONFIG(TAG, "Running setup");
+
+  const uint8_t data[2] = {
+      0b00000000,  // resolution 14bit for both humidity and temperature
+      0b00000000   // reserved
+  };
+
+  if (!this->write_bytes(HDC2010_CMD_CONFIGURATION_MEASUREMENT, data, 2)) {
+    ESP_LOGW(TAG, "Initial config instruction error");
+    this->status_set_warning();
+    return;
+  }
+
+  // Set measurement mode to temperature and humidity
+  uint8_t config_contents;
+  this->read_register(MEASUREMENT_CONFIG, &config_contents, 1);
+  config_contents = (config_contents & 0xF9);  // Always set to TEMP_AND_HUMID mode
+  this->write_bytes(MEASUREMENT_CONFIG, &config_contents, 1);
+
+  // Set rate to manual
+  this->read_register(CONFIG, &config_contents, 1);
+  config_contents &= 0x8F;
+  this->write_bytes(CONFIG, &config_contents, 1);
+
+  // Set temperature resolution to 14bit
+  this->read_register(CONFIG, &config_contents, 1);
+  config_contents &= 0x3F;
+  this->write_bytes(CONFIG, &config_contents, 1);
+
+  // Set humidity resolution to 14bit
+  this->read_register(CONFIG, &config_contents, 1);
+  config_contents &= 0xCF;
+  this->write_bytes(CONFIG, &config_contents, 1);
+}
+
+void HDC2010Component::dump_config() {
+  ESP_LOGCONFIG(TAG, "HDC2010:");
+  LOG_I2C_DEVICE(this);
+  if (this->is_failed()) {
+    ESP_LOGE(TAG, ESP_LOG_MSG_COMM_FAIL);
+  }
+  LOG_UPDATE_INTERVAL(this);
+  LOG_SENSOR("  ", "Temperature", this->temperature_sensor_);
+  LOG_SENSOR("  ", "Humidity", this->humidity_sensor_);
+}
+
+void HDC2010Component::update() {
+  // Trigger measurement
+  uint8_t config_contents;
+  this->read_register(CONFIG, &config_contents, 1);
+  config_contents |= 0x01;
+  this->write_bytes(MEASUREMENT_CONFIG, &config_contents, 1);
+
+  // 1ms delay after triggering the sample
+  set_timeout(1, [this]() {
+    if (this->temperature_sensor_ != nullptr) {
+      float temp = this->read_temp();
+      this->temperature_sensor_->publish_state(temp);
+      ESP_LOGD(TAG, "Temp=%.1f°C", temp);
+    }
+
+    if (this->humidity_sensor_ != nullptr) {
+      float humidity = this->read_humidity();
+      this->humidity_sensor_->publish_state(humidity);
+      ESP_LOGD(TAG, "Humidity=%.1f%%", humidity);
+    }
+  });
+}
+
+float HDC2010Component::read_temp() {
+  uint8_t byte[2];
+
+  this->read_register(HDC2010_CMD_TEMPERATURE_LOW, &byte[0], 1);
+  this->read_register(HDC2010_CMD_TEMPERATURE_HIGH, &byte[1], 1);
+
+  uint16_t temp = encode_uint16(byte[1], byte[0]);
+  return (float) temp * 0.0025177f - 40.0f;
+}
+
+float HDC2010Component::read_humidity() {
+  uint8_t byte[2];
+
+  this->read_register(HDC2010_CMD_HUMIDITY_LOW, &byte[0], 1);
+  this->read_register(HDC2010_CMD_HUMIDITY_HIGH, &byte[1], 1);
+
+  uint16_t humidity = encode_uint16(byte[1], byte[0]);
+  return (float) humidity * 0.001525879f;
+}
+
+}  // namespace hdc2010
+}  // namespace esphome

esphome/components/hdc2010/hdc2010.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/sensor/sensor.h"
+#include "esphome/components/i2c/i2c.h"
+
+namespace esphome {
+namespace hdc2010 {
+
+class HDC2010Component : public PollingComponent, public i2c::I2CDevice {
+ public:
+  void set_temperature_sensor(sensor::Sensor *temperature) { this->temperature_sensor_ = temperature; }
+
+  void set_humidity_sensor(sensor::Sensor *humidity) { this->humidity_sensor_ = humidity; }
+
+  /// Setup the sensor and check for connection.
+  void setup() override;
+  void dump_config() override;
+  /// Retrieve the latest sensor values. This operation takes approximately 16ms.
+  void update() override;
+
+  float read_temp();
+
+  float read_humidity();
+
+ protected:
+  sensor::Sensor *temperature_sensor_{nullptr};
+  sensor::Sensor *humidity_sensor_{nullptr};
+};
+
+}  // namespace hdc2010
+}  // namespace esphome

esphome/components/hdc2010/sensor.py

@@ -0,0 +1,56 @@
+import esphome.codegen as cg
+from esphome.components import i2c, sensor
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_HUMIDITY,
+    CONF_ID,
+    CONF_TEMPERATURE,
+    DEVICE_CLASS_HUMIDITY,
+    DEVICE_CLASS_TEMPERATURE,
+    STATE_CLASS_MEASUREMENT,
+    UNIT_CELSIUS,
+    UNIT_PERCENT,
+)
+
+DEPENDENCIES = ["i2c"]
+
+hdc2010_ns = cg.esphome_ns.namespace("hdc2010")
+HDC2010Component = hdc2010_ns.class_(
+    "HDC2010Component", cg.PollingComponent, i2c.I2CDevice
+)
+
+CONFIG_SCHEMA = (
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(HDC2010Component),
+            cv.Optional(CONF_TEMPERATURE): sensor.sensor_schema(
+                unit_of_measurement=UNIT_CELSIUS,
+                accuracy_decimals=1,
+                device_class=DEVICE_CLASS_TEMPERATURE,
+                state_class=STATE_CLASS_MEASUREMENT,
+            ),
+            cv.Optional(CONF_HUMIDITY): sensor.sensor_schema(
+                unit_of_measurement=UNIT_PERCENT,
+                accuracy_decimals=0,
+                device_class=DEVICE_CLASS_HUMIDITY,
+                state_class=STATE_CLASS_MEASUREMENT,
+            ),
+        }
+    )
+    .extend(cv.polling_component_schema("60s"))
+    .extend(i2c.i2c_device_schema(0x40))
+)
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    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))

esphome/components/heatpumpir/heatpumpir.h

@@ -97,12 +97,11 @@ const float TEMP_MAX = 100;  // Celsius
 class HeatpumpIRClimate : public climate_ir::ClimateIR {
  public:
   HeatpumpIRClimate()
-      : climate_ir::ClimateIR(
-            TEMP_MIN, TEMP_MAX, 1.0f, true, true,
-            std::set<climate::ClimateFanMode>{climate::CLIMATE_FAN_LOW, climate::CLIMATE_FAN_MEDIUM,
-                                              climate::CLIMATE_FAN_HIGH, climate::CLIMATE_FAN_AUTO},
-            std::set<climate::ClimateSwingMode>{climate::CLIMATE_SWING_OFF, climate::CLIMATE_SWING_HORIZONTAL,
-                                                climate::CLIMATE_SWING_VERTICAL, climate::CLIMATE_SWING_BOTH}) {}
+      : climate_ir::ClimateIR(TEMP_MIN, TEMP_MAX, 1.0f, true, true,
+                              {climate::CLIMATE_FAN_LOW, climate::CLIMATE_FAN_MEDIUM, climate::CLIMATE_FAN_HIGH,
+                               climate::CLIMATE_FAN_AUTO},
+                              {climate::CLIMATE_SWING_OFF, climate::CLIMATE_SWING_HORIZONTAL,
+                               climate::CLIMATE_SWING_VERTICAL, climate::CLIMATE_SWING_BOTH}) {}
   void setup() override;
   void set_protocol(Protocol protocol) { this->protocol_ = protocol; }
   void set_horizontal_default(HorizontalDirection horizontal_direction) {

esphome/components/host/gpio.h

@@ -28,8 +28,8 @@ class HostGPIOPin : public InternalGPIOPin {
   void attach_interrupt(void (*func)(void *), void *arg, gpio::InterruptType type) const override;
 
   uint8_t pin_;
-  bool inverted_;
-  gpio::Flags flags_;
+  bool inverted_{};
+  gpio::Flags flags_{};
 };
 
 }  // namespace host

esphome/components/host/gpio.py

@@ -57,6 +57,9 @@ async def host_pin_to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     num = config[CONF_NUMBER]
     cg.add(var.set_pin(num))
-    cg.add(var.set_inverted(config[CONF_INVERTED]))
+    # Only set if true to avoid bloating setup() function
+    # (inverted bit in pin_flags_ bitfield is zero-initialized to false)
+    if config[CONF_INVERTED]:
+        cg.add(var.set_inverted(True))
     cg.add(var.set_flags(pins.gpio_flags_expr(config[CONF_MODE])))
     return var

esphome/components/http_request/__init__.py

@@ -12,7 +12,6 @@ from esphome.const import (
     CONF_ON_ERROR,
     CONF_ON_RESPONSE,
     CONF_TIMEOUT,
-    CONF_TRIGGER_ID,
     CONF_URL,
     CONF_WATCHDOG_TIMEOUT,
     PLATFORM_HOST,
@@ -216,16 +215,8 @@ HTTP_REQUEST_ACTION_SCHEMA = cv.Schema(
             f"{CONF_VERIFY_SSL} has moved to the base component configuration."
         ),
         cv.Optional(CONF_CAPTURE_RESPONSE, default=False): cv.boolean,
-        cv.Optional(CONF_ON_RESPONSE): automation.validate_automation(
-            {cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(HttpRequestResponseTrigger)}
-        ),
-        cv.Optional(CONF_ON_ERROR): automation.validate_automation(
-            {
-                cv.GenerateID(CONF_TRIGGER_ID): cv.declare_id(
-                    automation.Trigger.template()
-                )
-            }
-        ),
+        cv.Optional(CONF_ON_RESPONSE): automation.validate_automation(single=True),
+        cv.Optional(CONF_ON_ERROR): automation.validate_automation(single=True),
         cv.Optional(CONF_MAX_RESPONSE_BUFFER_SIZE, default="1kB"): cv.validate_bytes,
     }
 )
@@ -280,7 +271,12 @@ async def http_request_action_to_code(config, action_id, template_arg, args):
     template_ = await cg.templatable(config[CONF_URL], args, cg.std_string)
     cg.add(var.set_url(template_))
     cg.add(var.set_method(config[CONF_METHOD]))
-    cg.add(var.set_capture_response(config[CONF_CAPTURE_RESPONSE]))
+
+    capture_response = config[CONF_CAPTURE_RESPONSE]
+    if capture_response:
+        cg.add(var.set_capture_response(capture_response))
+        cg.add_define("USE_HTTP_REQUEST_RESPONSE")
+
     cg.add(var.set_max_response_buffer_size(config[CONF_MAX_RESPONSE_BUFFER_SIZE]))
 
     if CONF_BODY in config:
@@ -303,21 +299,26 @@ async def http_request_action_to_code(config, action_id, template_arg, args):
     for value in config.get(CONF_COLLECT_HEADERS, []):
         cg.add(var.add_collect_header(value))
 
-    for conf in config.get(CONF_ON_RESPONSE, []):
-        trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID])
-        cg.add(var.register_response_trigger(trigger))
-        await automation.build_automation(
-            trigger,
-            [
-                (cg.std_shared_ptr.template(HttpContainer), "response"),
-                (cg.std_string_ref, "body"),
-            ],
-            conf,
-        )
-    for conf in config.get(CONF_ON_ERROR, []):
-        trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID])
-        cg.add(var.register_error_trigger(trigger))
-        await automation.build_automation(trigger, [], conf)
+    if response_conf := config.get(CONF_ON_RESPONSE):
+        if capture_response:
+            await automation.build_automation(
+                var.get_success_trigger_with_response(),
+                [
+                    (cg.std_shared_ptr.template(HttpContainer), "response"),
+                    (cg.std_string_ref, "body"),
+                    *args,
+                ],
+                response_conf,
+            )
+        else:
+            await automation.build_automation(
+                var.get_success_trigger(),
+                [(cg.std_shared_ptr.template(HttpContainer), "response"), *args],
+                response_conf,
+            )
+
+    if error_conf := config.get(CONF_ON_ERROR):
+        await automation.build_automation(var.get_error_trigger(), args, error_conf)
 
     return var
 

esphome/components/http_request/http_request.h

@@ -124,7 +124,7 @@ class HttpRequestComponent : public Component {
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
 
   void set_useragent(const char *useragent) { this->useragent_ = useragent; }
-  void set_timeout(uint16_t timeout) { this->timeout_ = timeout; }
+  void set_timeout(uint32_t timeout) { this->timeout_ = timeout; }
   void set_watchdog_timeout(uint32_t watchdog_timeout) { this->watchdog_timeout_ = watchdog_timeout; }
   uint32_t get_watchdog_timeout() const { return this->watchdog_timeout_; }
   void set_follow_redirects(bool follow_redirects) { this->follow_redirects_ = follow_redirects; }
@@ -169,11 +169,11 @@ class HttpRequestComponent : public Component {
  protected:
   virtual std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method,
                                                  const std::string &body, const std::list<Header> &request_headers,
-                                                 std::set<std::string> collect_headers) = 0;
+                                                 const std::set<std::string> &collect_headers) = 0;
   const char *useragent_{nullptr};
   bool follow_redirects_{};
   uint16_t redirect_limit_{};
-  uint16_t timeout_{4500};
+  uint32_t timeout_{4500};
   uint32_t watchdog_timeout_{0};
 };
 
@@ -183,7 +183,9 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
   TEMPLATABLE_VALUE(std::string, url)
   TEMPLATABLE_VALUE(const char *, method)
   TEMPLATABLE_VALUE(std::string, body)
+#ifdef USE_HTTP_REQUEST_RESPONSE
   TEMPLATABLE_VALUE(bool, capture_response)
+#endif
 
   void add_request_header(const char *key, TemplatableValue<const char *, Ts...> value) {
     this->request_headers_.insert({key, value});
@@ -195,9 +197,14 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
 
   void set_json(std::function<void(Ts..., JsonObject)> json_func) { this->json_func_ = json_func; }
 
-  void register_response_trigger(HttpRequestResponseTrigger *trigger) { this->response_triggers_.push_back(trigger); }
+#ifdef USE_HTTP_REQUEST_RESPONSE
+  Trigger<std::shared_ptr<HttpContainer>, std::string &, Ts...> *get_success_trigger_with_response() const {
+    return this->success_trigger_with_response_;
+  }
+#endif
+  Trigger<std::shared_ptr<HttpContainer>, Ts...> *get_success_trigger() const { return this->success_trigger_; }
 
-  void register_error_trigger(Trigger<> *trigger) { this->error_triggers_.push_back(trigger); }
+  Trigger<Ts...> *get_error_trigger() const { return this->error_trigger_; }
 
   void set_max_response_buffer_size(size_t max_response_buffer_size) {
     this->max_response_buffer_size_ = max_response_buffer_size;
@@ -228,17 +235,20 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
     auto container = this->parent_->start(this->url_.value(x...), this->method_.value(x...), body, request_headers,
                                           this->collect_headers_);
 
+    auto captured_args = std::make_tuple(x...);
+
     if (container == nullptr) {
-      for (auto *trigger : this->error_triggers_)
-        trigger->trigger();
+      std::apply([this](Ts... captured_args_inner) { this->error_trigger_->trigger(captured_args_inner...); },
+                 captured_args);
       return;
     }
 
     size_t content_length = container->content_length;
     size_t max_length = std::min(content_length, this->max_response_buffer_size_);
 
-    std::string response_body;
+#ifdef USE_HTTP_REQUEST_RESPONSE
     if (this->capture_response_.value(x...)) {
+      std::string response_body;
       RAMAllocator<uint8_t> allocator;
       uint8_t *buf = allocator.allocate(max_length);
       if (buf != nullptr) {
@@ -253,19 +263,17 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
         response_body.assign((char *) buf, read_index);
         allocator.deallocate(buf, max_length);
       }
-    }
-
-    if (this->response_triggers_.size() == 1) {
-      // if there is only one trigger, no need to copy the response body
-      this->response_triggers_[0]->process(container, response_body);
-    } else {
-      for (auto *trigger : this->response_triggers_) {
-        // with multiple triggers, pass a copy of the response body to each
-        // one so that modifications made in one trigger are not visible to
-        // the others
-        auto response_body_copy = std::string(response_body);
-        trigger->process(container, response_body_copy);
-      }
+      std::apply(
+          [this, &container, &response_body](Ts... captured_args_inner) {
+            this->success_trigger_with_response_->trigger(container, response_body, captured_args_inner...);
+          },
+          captured_args);
+    } else
+#endif
+    {
+      std::apply([this, &container](
+                     Ts... captured_args_inner) { this->success_trigger_->trigger(container, captured_args_inner...); },
+                 captured_args);
     }
     container->end();
   }
@@ -283,8 +291,13 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
   std::set<std::string> collect_headers_{"content-type", "content-length"};
   std::map<const char *, TemplatableValue<std::string, Ts...>> json_{};
   std::function<void(Ts..., JsonObject)> json_func_{nullptr};
-  std::vector<HttpRequestResponseTrigger *> response_triggers_{};
-  std::vector<Trigger<> *> error_triggers_{};
+#ifdef USE_HTTP_REQUEST_RESPONSE
+  Trigger<std::shared_ptr<HttpContainer>, std::string &, Ts...> *success_trigger_with_response_ =
+      new Trigger<std::shared_ptr<HttpContainer>, std::string &, Ts...>();
+#endif
+  Trigger<std::shared_ptr<HttpContainer>, Ts...> *success_trigger_ =
+      new Trigger<std::shared_ptr<HttpContainer>, Ts...>();
+  Trigger<Ts...> *error_trigger_ = new Trigger<Ts...>();
 
   size_t max_response_buffer_size_{SIZE_MAX};
 };

esphome/components/http_request/http_request_arduino.cpp

@@ -17,7 +17,7 @@ static const char *const TAG = "http_request.arduino";
 std::shared_ptr<HttpContainer> HttpRequestArduino::perform(const std::string &url, const std::string &method,
                                                            const std::string &body,
                                                            const std::list<Header> &request_headers,
-                                                           std::set<std::string> collect_headers) {
+                                                           const std::set<std::string> &collect_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);
     ESP_LOGW(TAG, "HTTP Request failed; Not connected to network");

esphome/components/http_request/http_request_arduino.h

@@ -33,7 +33,7 @@ class HttpRequestArduino : public HttpRequestComponent {
  protected:
   std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
                                          const std::list<Header> &request_headers,
-                                         std::set<std::string> collect_headers) override;
+                                         const std::set<std::string> &collect_headers) override;
 };
 
 }  // namespace http_request

esphome/components/http_request/http_request_host.cpp

@@ -20,7 +20,7 @@ static const char *const TAG = "http_request.host";
 std::shared_ptr<HttpContainer> HttpRequestHost::perform(const std::string &url, const std::string &method,
                                                         const std::string &body,
                                                         const std::list<Header> &request_headers,
-                                                        std::set<std::string> response_headers) {
+                                                        const std::set<std::string> &response_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);
     ESP_LOGW(TAG, "HTTP Request failed; Not connected to network");

esphome/components/http_request/http_request_host.h

@@ -20,7 +20,7 @@ class HttpRequestHost : public HttpRequestComponent {
  public:
   std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
                                          const std::list<Header> &request_headers,
-                                         std::set<std::string> response_headers) override;
+                                         const std::set<std::string> &response_headers) override;
   void set_ca_path(const char *ca_path) { this->ca_path_ = ca_path; }
 
  protected:

esphome/components/http_request/http_request_idf.cpp

@@ -55,7 +55,7 @@ esp_err_t HttpRequestIDF::http_event_handler(esp_http_client_event_t *evt) {
 std::shared_ptr<HttpContainer> HttpRequestIDF::perform(const std::string &url, const std::string &method,
                                                        const std::string &body,
                                                        const std::list<Header> &request_headers,
-                                                       std::set<std::string> collect_headers) {
+                                                       const std::set<std::string> &collect_headers) {
   if (!network::is_connected()) {
     this->status_momentary_error("failed", 1000);
     ESP_LOGE(TAG, "HTTP Request failed; Not connected to network");

esphome/components/http_request/http_request_idf.h

@@ -39,7 +39,7 @@ class HttpRequestIDF : public HttpRequestComponent {
  protected:
   std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
                                          const std::list<Header> &request_headers,
-                                         std::set<std::string> collect_headers) override;
+                                         const std::set<std::string> &collect_headers) override;
   // if zero ESP-IDF will use DEFAULT_HTTP_BUF_SIZE
   uint16_t buffer_size_rx_{};
   uint16_t buffer_size_tx_{};

esphome/components/improv_base/__init__.py

@@ -3,6 +3,8 @@ import re
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.const import __version__
+from esphome.cpp_generator import MockObj
+from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core"]
 
@@ -35,7 +37,9 @@ def _process_next_url(url: str):
     return url
 
 
-async def setup_improv_core(var, config):
-    if CONF_NEXT_URL in config:
-        cg.add(var.set_next_url(_process_next_url(config[CONF_NEXT_URL])))
+async def setup_improv_core(var: MockObj, config: ConfigType, component: str):
+    if next_url := config.get(CONF_NEXT_URL):
+        cg.add(var.set_next_url(_process_next_url(next_url)))
+        cg.add_define(f"USE_{component.upper()}_NEXT_URL")
+
     cg.add_library("improv/Improv", "1.2.4")

esphome/components/improv_base/improv_base.cpp

@@ -2,10 +2,12 @@
 
 #include "esphome/components/network/util.h"
 #include "esphome/core/application.h"
+#include "esphome/core/defines.h"
 
 namespace esphome {
 namespace improv_base {
 
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
 static constexpr const char DEVICE_NAME_PLACEHOLDER[] = "{{device_name}}";
 static constexpr size_t DEVICE_NAME_PLACEHOLDER_LEN = sizeof(DEVICE_NAME_PLACEHOLDER) - 1;
 static constexpr const char IP_ADDRESS_PLACEHOLDER[] = "{{ip_address}}";
@@ -43,6 +45,7 @@ std::string ImprovBase::get_formatted_next_url_() {
 
   return formatted_url;
 }
+#endif
 
 }  // namespace improv_base
 }  // namespace esphome

esphome/components/improv_base/improv_base.h

@@ -1,17 +1,22 @@
 #pragma once
 
 #include <string>
+#include "esphome/core/defines.h"
 
 namespace esphome {
 namespace improv_base {
 
 class ImprovBase {
  public:
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
   void set_next_url(const std::string &next_url) { this->next_url_ = next_url; }
+#endif
 
  protected:
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
   std::string get_formatted_next_url_();
   std::string next_url_;
+#endif
 };
 
 }  // namespace improv_base

esphome/components/improv_serial/__init__.py

@@ -43,4 +43,4 @@ FINAL_VALIDATE_SCHEMA = validate_logger
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
-    await improv_base.setup_improv_core(var, config)
+    await improv_base.setup_improv_core(var, config, "improv_serial")

esphome/components/improv_serial/improv_serial_component.cpp

@@ -28,6 +28,38 @@ void ImprovSerialComponent::setup() {
   }
 }
 
+void ImprovSerialComponent::loop() {
+  if (this->last_read_byte_ && (millis() - this->last_read_byte_ > IMPROV_SERIAL_TIMEOUT)) {
+    this->last_read_byte_ = 0;
+    this->rx_buffer_.clear();
+    ESP_LOGV(TAG, "Timeout");
+  }
+
+  auto byte = this->read_byte_();
+  while (byte.has_value()) {
+    if (this->parse_improv_serial_byte_(byte.value())) {
+      this->last_read_byte_ = millis();
+    } else {
+      this->last_read_byte_ = 0;
+      this->rx_buffer_.clear();
+    }
+    byte = this->read_byte_();
+  }
+
+  if (this->state_ == improv::STATE_PROVISIONING) {
+    if (wifi::global_wifi_component->is_connected()) {
+      wifi::global_wifi_component->save_wifi_sta(this->connecting_sta_.get_ssid(),
+                                                 this->connecting_sta_.get_password());
+      this->connecting_sta_ = {};
+      this->cancel_timeout("wifi-connect-timeout");
+      this->set_state_(improv::STATE_PROVISIONED);
+
+      std::vector<uint8_t> url = this->build_rpc_settings_response_(improv::WIFI_SETTINGS);
+      this->send_response_(url);
+    }
+  }
+}
+
 void ImprovSerialComponent::dump_config() { ESP_LOGCONFIG(TAG, "Improv Serial:"); }
 
 optional<uint8_t> ImprovSerialComponent::read_byte_() {
@@ -78,8 +110,28 @@ optional<uint8_t> ImprovSerialComponent::read_byte_() {
   return byte;
 }
 
-void ImprovSerialComponent::write_data_(std::vector<uint8_t> &data) {
-  data.push_back('\n');
+void ImprovSerialComponent::write_data_(const uint8_t *data, const size_t size) {
+  // First, set length field
+  this->tx_header_[TX_LENGTH_IDX] = this->tx_header_[TX_TYPE_IDX] == TYPE_RPC_RESPONSE ? size : 1;
+
+  const bool there_is_data = data != nullptr && size > 0;
+  // If there_is_data, checksum must not include our optional data byte
+  const uint8_t header_checksum_len = there_is_data ? TX_BUFFER_SIZE - 3 : TX_BUFFER_SIZE - 2;
+  // Only transmit the full buffer length if there is no data (only state/error byte is provided in this case)
+  const uint8_t header_tx_len = there_is_data ? TX_BUFFER_SIZE - 3 : TX_BUFFER_SIZE;
+  // Calculate checksum for message
+  uint8_t checksum = 0;
+  for (uint8_t i = 0; i < header_checksum_len; i++) {
+    checksum += this->tx_header_[i];
+  }
+  if (there_is_data) {
+    // Include data in checksum
+    for (size_t i = 0; i < size; i++) {
+      checksum += data[i];
+    }
+  }
+  this->tx_header_[TX_CHECKSUM_IDX] = checksum;
+
 #ifdef USE_ESP32
   switch (logger::global_logger->get_uart()) {
     case logger::UART_SELECTION_UART0:
@@ -87,68 +139,52 @@ void ImprovSerialComponent::write_data_(std::vector<uint8_t> &data) {
 #if !defined(USE_ESP32_VARIANT_ESP32C3) && !defined(USE_ESP32_VARIANT_ESP32C6) && \
     !defined(USE_ESP32_VARIANT_ESP32S2) && !defined(USE_ESP32_VARIANT_ESP32S3)
     case logger::UART_SELECTION_UART2:
-#endif  // !USE_ESP32_VARIANT_ESP32C3 && !USE_ESP32_VARIANT_ESP32S2 && !USE_ESP32_VARIANT_ESP32S3
-      uart_write_bytes(this->uart_num_, data.data(), data.size());
+#endif
+      uart_write_bytes(this->uart_num_, this->tx_header_, header_tx_len);
+      if (there_is_data) {
+        uart_write_bytes(this->uart_num_, data, size);
+        uart_write_bytes(this->uart_num_, &this->tx_header_[TX_CHECKSUM_IDX], 2);  // Footer: checksum and newline
+      }
       break;
 #if defined(USE_LOGGER_USB_CDC) && defined(CONFIG_ESP_CONSOLE_USB_CDC)
-    case logger::UART_SELECTION_USB_CDC: {
-      const char *msg = (char *) data.data();
-      esp_usb_console_write_buf(msg, data.size());
+    case logger::UART_SELECTION_USB_CDC:
+      esp_usb_console_write_buf((const char *) this->tx_header_, header_tx_len);
+      if (there_is_data) {
+        esp_usb_console_write_buf((const char *) data, size);
+        esp_usb_console_write_buf((const char *) &this->tx_header_[TX_CHECKSUM_IDX],
+                                  2);  // Footer: checksum and newline
+      }
       break;
-    }
-#endif  // USE_LOGGER_USB_CDC
+#endif
 #ifdef USE_LOGGER_USB_SERIAL_JTAG
     case logger::UART_SELECTION_USB_SERIAL_JTAG:
-      usb_serial_jtag_write_bytes((char *) data.data(), data.size(), 20 / portTICK_PERIOD_MS);
-      delay(10);
-      usb_serial_jtag_ll_txfifo_flush();  // fixes for issue in IDF 4.4.7
+      usb_serial_jtag_write_bytes((const char *) this->tx_header_, header_tx_len, 20 / portTICK_PERIOD_MS);
+      if (there_is_data) {
+        usb_serial_jtag_write_bytes((const char *) data, size, 20 / portTICK_PERIOD_MS);
+        usb_serial_jtag_write_bytes((const char *) &this->tx_header_[TX_CHECKSUM_IDX], 2,
+                                    20 / portTICK_PERIOD_MS);  // Footer: checksum and newline
+      }
       break;
-#endif  // USE_LOGGER_USB_SERIAL_JTAG
+#endif
     default:
       break;
   }
 #elif defined(USE_ARDUINO)
-  this->hw_serial_->write(data.data(), data.size());
+  this->hw_serial_->write(this->tx_header_, header_tx_len);
+  if (there_is_data) {
+    this->hw_serial_->write(data, size);
+    this->hw_serial_->write(&this->tx_header_[TX_CHECKSUM_IDX], 2);  // Footer: checksum and newline
+  }
 #endif
 }
 
-void ImprovSerialComponent::loop() {
-  if (this->last_read_byte_ && (millis() - this->last_read_byte_ > IMPROV_SERIAL_TIMEOUT)) {
-    this->last_read_byte_ = 0;
-    this->rx_buffer_.clear();
-    ESP_LOGV(TAG, "Improv Serial timeout");
-  }
-
-  auto byte = this->read_byte_();
-  while (byte.has_value()) {
-    if (this->parse_improv_serial_byte_(byte.value())) {
-      this->last_read_byte_ = millis();
-    } else {
-      this->last_read_byte_ = 0;
-      this->rx_buffer_.clear();
-    }
-    byte = this->read_byte_();
-  }
-
-  if (this->state_ == improv::STATE_PROVISIONING) {
-    if (wifi::global_wifi_component->is_connected()) {
-      wifi::global_wifi_component->save_wifi_sta(this->connecting_sta_.get_ssid(),
-                                                 this->connecting_sta_.get_password());
-      this->connecting_sta_ = {};
-      this->cancel_timeout("wifi-connect-timeout");
-      this->set_state_(improv::STATE_PROVISIONED);
-
-      std::vector<uint8_t> url = this->build_rpc_settings_response_(improv::WIFI_SETTINGS);
-      this->send_response_(url);
-    }
-  }
-}
-
 std::vector<uint8_t> ImprovSerialComponent::build_rpc_settings_response_(improv::Command command) {
   std::vector<std::string> urls;
+#ifdef USE_IMPROV_SERIAL_NEXT_URL
   if (!this->next_url_.empty()) {
     urls.push_back(this->get_formatted_next_url_());
   }
+#endif
 #ifdef USE_WEBSERVER
   for (auto &ip : wifi::global_wifi_component->wifi_sta_ip_addresses()) {
     if (ip.is_ip4()) {
@@ -175,13 +211,13 @@ std::vector<uint8_t> ImprovSerialComponent::build_version_info_() {
 bool ImprovSerialComponent::parse_improv_serial_byte_(uint8_t byte) {
   size_t at = this->rx_buffer_.size();
   this->rx_buffer_.push_back(byte);
-  ESP_LOGV(TAG, "Improv Serial byte: 0x%02X", byte);
+  ESP_LOGV(TAG, "Byte: 0x%02X", byte);
   const uint8_t *raw = &this->rx_buffer_[0];
 
   return improv::parse_improv_serial_byte(
       at, byte, raw, [this](improv::ImprovCommand command) -> bool { return this->parse_improv_payload_(command); },
       [this](improv::Error error) -> void {
-        ESP_LOGW(TAG, "Error decoding Improv payload");
+        ESP_LOGW(TAG, "Error decoding payload");
         this->set_error_(error);
       });
 }
@@ -197,7 +233,7 @@ bool ImprovSerialComponent::parse_improv_payload_(improv::ImprovCommand &command
       wifi::global_wifi_component->set_sta(sta);
       wifi::global_wifi_component->start_connecting(sta, false);
       this->set_state_(improv::STATE_PROVISIONING);
-      ESP_LOGD(TAG, "Received Improv wifi settings ssid=%s, password=" LOG_SECRET("%s"), command.ssid.c_str(),
+      ESP_LOGD(TAG, "Received settings: SSID=%s, password=" LOG_SECRET("%s"), command.ssid.c_str(),
                command.password.c_str());
 
       auto f = std::bind(&ImprovSerialComponent::on_wifi_connect_timeout_, this);
@@ -238,7 +274,7 @@ bool ImprovSerialComponent::parse_improv_payload_(improv::ImprovCommand &command
       return true;
     }
     default: {
-      ESP_LOGW(TAG, "Unknown Improv payload");
+      ESP_LOGW(TAG, "Unknown payload");
       this->set_error_(improv::ERROR_UNKNOWN_RPC);
       return false;
     }
@@ -247,57 +283,26 @@ bool ImprovSerialComponent::parse_improv_payload_(improv::ImprovCommand &command
 
 void ImprovSerialComponent::set_state_(improv::State state) {
   this->state_ = state;
-
-  std::vector<uint8_t> data = {'I', 'M', 'P', 'R', 'O', 'V'};
-  data.resize(11);
-  data[6] = IMPROV_SERIAL_VERSION;
-  data[7] = TYPE_CURRENT_STATE;
-  data[8] = 1;
-  data[9] = state;
-
-  uint8_t checksum = 0x00;
-  for (uint8_t d : data)
-    checksum += d;
-  data[10] = checksum;
-
-  this->write_data_(data);
+  this->tx_header_[TX_TYPE_IDX] = TYPE_CURRENT_STATE;
+  this->tx_header_[TX_DATA_IDX] = state;
+  this->write_data_();
 }
 
 void ImprovSerialComponent::set_error_(improv::Error error) {
-  std::vector<uint8_t> data = {'I', 'M', 'P', 'R', 'O', 'V'};
-  data.resize(11);
-  data[6] = IMPROV_SERIAL_VERSION;
-  data[7] = TYPE_ERROR_STATE;
-  data[8] = 1;
-  data[9] = error;
-
-  uint8_t checksum = 0x00;
-  for (uint8_t d : data)
-    checksum += d;
-  data[10] = checksum;
-  this->write_data_(data);
+  this->tx_header_[TX_TYPE_IDX] = TYPE_ERROR_STATE;
+  this->tx_header_[TX_DATA_IDX] = error;
+  this->write_data_();
 }
 
 void ImprovSerialComponent::send_response_(std::vector<uint8_t> &response) {
-  std::vector<uint8_t> data = {'I', 'M', 'P', 'R', 'O', 'V'};
-  data.resize(9);
-  data[6] = IMPROV_SERIAL_VERSION;
-  data[7] = TYPE_RPC_RESPONSE;
-  data[8] = response.size();
-  data.insert(data.end(), response.begin(), response.end());
-
-  uint8_t checksum = 0x00;
-  for (uint8_t d : data)
-    checksum += d;
-  data.push_back(checksum);
-
-  this->write_data_(data);
+  this->tx_header_[TX_TYPE_IDX] = TYPE_RPC_RESPONSE;
+  this->write_data_(response.data(), response.size());
 }
 
 void ImprovSerialComponent::on_wifi_connect_timeout_() {
   this->set_error_(improv::ERROR_UNABLE_TO_CONNECT);
   this->set_state_(improv::STATE_AUTHORIZED);
-  ESP_LOGW(TAG, "Timed out trying to connect to given WiFi network");
+  ESP_LOGW(TAG, "Timed out while connecting to Wi-Fi network");
   wifi::global_wifi_component->clear_sta();
 }
 

esphome/components/improv_serial/improv_serial_component.h

@@ -26,6 +26,16 @@
 namespace esphome {
 namespace improv_serial {
 
+// TX buffer layout constants
+static constexpr uint8_t TX_HEADER_SIZE = 6;  // Bytes 0-5 = "IMPROV"
+static constexpr uint8_t TX_VERSION_IDX = 6;
+static constexpr uint8_t TX_TYPE_IDX = 7;
+static constexpr uint8_t TX_LENGTH_IDX = 8;
+static constexpr uint8_t TX_DATA_IDX = 9;  // For state/error messages only
+static constexpr uint8_t TX_CHECKSUM_IDX = 10;
+static constexpr uint8_t TX_NEWLINE_IDX = 11;
+static constexpr uint8_t TX_BUFFER_SIZE = 12;
+
 enum ImprovSerialType : uint8_t {
   TYPE_CURRENT_STATE = 0x01,
   TYPE_ERROR_STATE = 0x02,
@@ -57,7 +67,22 @@ class ImprovSerialComponent : public Component, public improv_base::ImprovBase {
   std::vector<uint8_t> build_version_info_();
 
   optional<uint8_t> read_byte_();
-  void write_data_(std::vector<uint8_t> &data);
+  void write_data_(const uint8_t *data = nullptr, size_t size = 0);
+
+  uint8_t tx_header_[TX_BUFFER_SIZE] = {
+      'I',                    // 0: Header
+      'M',                    // 1: Header
+      'P',                    // 2: Header
+      'R',                    // 3: Header
+      'O',                    // 4: Header
+      'V',                    // 5: Header
+      IMPROV_SERIAL_VERSION,  // 6: Version
+      0,                      // 7: ImprovSerialType
+      0,                      // 8: Length
+      0,                      // 9...X: Data (here, one byte reserved for state/error)
+      0,                      // X + 10: Checksum
+      '\n',
+  };
 
 #ifdef USE_ESP32
   uart_port_t uart_num_;

esphome/components/libretiny/gpio.py

@@ -199,6 +199,9 @@ async def component_pin_to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     num = config[CONF_NUMBER]
     cg.add(var.set_pin(num))
-    cg.add(var.set_inverted(config[CONF_INVERTED]))
+    # Only set if true to avoid bloating setup() function
+    # (inverted bit in pin_flags_ bitfield is zero-initialized to false)
+    if config[CONF_INVERTED]:
+        cg.add(var.set_inverted(True))
     cg.add(var.set_flags(pins.gpio_flags_expr(config[CONF_MODE])))
     return var

esphome/components/libretiny/gpio_arduino.h

@@ -27,8 +27,8 @@ class ArduinoInternalGPIOPin : public InternalGPIOPin {
   void attach_interrupt(void (*func)(void *), void *arg, gpio::InterruptType type) const override;
 
   uint8_t pin_;
-  bool inverted_;
-  gpio::Flags flags_;
+  bool inverted_{};
+  gpio::Flags flags_{};
 };
 
 }  // namespace libretiny

esphome/components/light/addressable_light.cpp

@@ -61,8 +61,12 @@ void AddressableLightTransformer::start() {
   this->target_color_ *= to_uint8_scale(end_values.get_brightness() * end_values.get_state());
 }
 
+inline constexpr uint8_t subtract_scaled_difference(uint8_t a, uint8_t b, int32_t scale) {
+  return uint8_t(int32_t(a) - (((int32_t(a) - int32_t(b)) * scale) / 256));
+}
+
 optional<LightColorValues> AddressableLightTransformer::apply() {
-  float smoothed_progress = LightTransitionTransformer::smoothed_progress(this->get_progress_());
+  float smoothed_progress = LightTransformer::smoothed_progress(this->get_progress_());
 
   // When running an output-buffer modifying effect, don't try to transition individual LEDs, but instead just fade the
   // LightColorValues. write_state() then picks up the change in brightness, and the color change is picked up by the
@@ -74,38 +78,37 @@ optional<LightColorValues> AddressableLightTransformer::apply() {
   // all LEDs, we use the current state of each LED as the start.
 
   // We can't use a direct lerp smoothing here though - that would require creating a copy of the original
-  // state of each LED at the start of the transition.
-  // Instead, we "fake" the look of the LERP by using an exponential average over time and using
-  // dynamically-calculated alpha values to match the look.
+  // state of each LED at the start of the transition. Instead, we "fake" the look of lerp by calculating
+  // the delta between the current state and the target state, assuming that the delta represents the rest
+  // of the transition that was to be applied as of the previous transition step, and scaling the delta for
+  // what should be left after the current transition step. In this manner, the delta decays to zero as the
+  // transition progresses.
+  //
+  // Here's an example of how the algorithm progresses in discrete steps:
+  //
+  // At time = 0.00, 0% complete, 100% remaining, 100% will remain after this step, so the scale is 100% / 100% = 100%.
+  // At time = 0.10, 0% complete, 100% remaining, 90% will remain after this step, so the scale is 90% / 100% = 90%.
+  // At time = 0.20, 10% complete, 90% remaining, 80% will remain after this step, so the scale is 80% / 90% = 88.9%.
+  // At time = 0.50, 20% complete, 80% remaining, 50% will remain after this step, so the scale is 50% / 80% = 62.5%.
+  // At time = 0.90, 50% complete, 50% remaining, 10% will remain after this step, so the scale is 10% / 50% = 20%.
+  // At time = 0.91, 90% complete, 10% remaining, 9% will remain after this step, so the scale is 9% / 10% = 90%.
+  // At time = 1.00, 91% complete, 9% remaining, 0% will remain after this step, so the scale is 0% / 9% = 0%.
+  //
+  // Because the color values are quantized to 8 bit resolution after each step, the transition may appear
+  // non-linear when applying small deltas.
 
-  float denom = (1.0f - smoothed_progress);
-  float alpha = denom == 0.0f ? 1.0f : (smoothed_progress - this->last_transition_progress_) / denom;
-
-  // We need to use a low-resolution alpha here which makes the transition set in only after ~half of the length
-  // We solve this by accumulating the fractional part of the alpha over time.
-  float alpha255 = alpha * 255.0f;
-  float alpha255int = floorf(alpha255);
-  float alpha255remainder = alpha255 - alpha255int;
-
-  this->accumulated_alpha_ += alpha255remainder;
-  float alpha_add = floorf(this->accumulated_alpha_);
-  this->accumulated_alpha_ -= alpha_add;
-
-  alpha255 += alpha_add;
-  alpha255 = clamp(alpha255, 0.0f, 255.0f);
-  auto alpha8 = static_cast<uint8_t>(alpha255);
-
-  if (alpha8 != 0) {
-    uint8_t inv_alpha8 = 255 - alpha8;
-    Color add = this->target_color_ * alpha8;
-
-    for (auto led : this->light_)
-      led.set(add + led.get() * inv_alpha8);
+  if (smoothed_progress > this->last_transition_progress_ && this->last_transition_progress_ < 1.f) {
+    int32_t scale = int32_t(256.f * std::max((1.f - smoothed_progress) / (1.f - this->last_transition_progress_), 0.f));
+    for (auto led : this->light_) {
+      led.set_rgbw(subtract_scaled_difference(this->target_color_.red, led.get_red(), scale),
+                   subtract_scaled_difference(this->target_color_.green, led.get_green(), scale),
+                   subtract_scaled_difference(this->target_color_.blue, led.get_blue(), scale),
+                   subtract_scaled_difference(this->target_color_.white, led.get_white(), scale));
+    }
+    this->last_transition_progress_ = smoothed_progress;
+    this->light_.schedule_show();
   }
 
-  this->last_transition_progress_ = smoothed_progress;
-  this->light_.schedule_show();
-
   return {};
 }
 

esphome/components/light/addressable_light.h

@@ -8,7 +8,7 @@
 #include "esphome/core/defines.h"
 #include "light_output.h"
 #include "light_state.h"
-#include "transformers.h"
+#include "light_transformer.h"
 
 #ifdef USE_POWER_SUPPLY
 #include "esphome/components/power_supply/power_supply.h"
@@ -103,7 +103,7 @@ class AddressableLight : public LightOutput, public Component {
   bool effect_active_{false};
 };
 
-class AddressableLightTransformer : public LightTransitionTransformer {
+class AddressableLightTransformer : public LightTransformer {
  public:
   AddressableLightTransformer(AddressableLight &light) : light_(light) {}
 
@@ -113,7 +113,6 @@ class AddressableLightTransformer : public LightTransitionTransformer {
  protected:
   AddressableLight &light_;
   float last_transition_progress_{0.0f};
-  float accumulated_alpha_{0.0f};
   Color target_color_{};
 };
 

esphome/components/light/addressable_light_effect.h

@@ -1,9 +1,9 @@
 #pragma once
 
 #include <utility>
-#include <vector>
 
 #include "esphome/core/component.h"
+#include "esphome/core/helpers.h"
 #include "esphome/components/light/light_state.h"
 #include "esphome/components/light/addressable_light.h"
 
@@ -30,7 +30,7 @@ inline static uint8_t half_sin8(uint8_t v) { return sin16_c(uint16_t(v) * 128u)
 
 class AddressableLightEffect : public LightEffect {
  public:
-  explicit AddressableLightEffect(const std::string &name) : LightEffect(name) {}
+  explicit AddressableLightEffect(const char *name) : LightEffect(name) {}
   void start_internal() override {
     this->get_addressable_()->set_effect_active(true);
     this->get_addressable_()->clear_effect_data();
@@ -57,10 +57,9 @@ class AddressableLightEffect : public LightEffect {
 
 class AddressableLambdaLightEffect : public AddressableLightEffect {
  public:
-  AddressableLambdaLightEffect(const std::string &name,
-                               std::function<void(AddressableLight &, Color, bool initial_run)> f,
+  AddressableLambdaLightEffect(const char *name, void (*f)(AddressableLight &, Color, bool initial_run),
                                uint32_t update_interval)
-      : AddressableLightEffect(name), f_(std::move(f)), update_interval_(update_interval) {}
+      : AddressableLightEffect(name), f_(f), update_interval_(update_interval) {}
   void start() override { this->initial_run_ = true; }
   void apply(AddressableLight &it, const Color &current_color) override {
     const uint32_t now = millis();
@@ -73,7 +72,7 @@ class AddressableLambdaLightEffect : public AddressableLightEffect {
   }
 
  protected:
-  std::function<void(AddressableLight &, Color, bool initial_run)> f_;
+  void (*f_)(AddressableLight &, Color, bool initial_run);
   uint32_t update_interval_;
   uint32_t last_run_{0};
   bool initial_run_;
@@ -81,7 +80,7 @@ class AddressableLambdaLightEffect : public AddressableLightEffect {
 
 class AddressableRainbowLightEffect : public AddressableLightEffect {
  public:
-  explicit AddressableRainbowLightEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableRainbowLightEffect(const char *name) : AddressableLightEffect(name) {}
   void apply(AddressableLight &it, const Color &current_color) override {
     ESPHSVColor hsv;
     hsv.value = 255;
@@ -112,8 +111,8 @@ struct AddressableColorWipeEffectColor {
 
 class AddressableColorWipeEffect : public AddressableLightEffect {
  public:
-  explicit AddressableColorWipeEffect(const std::string &name) : AddressableLightEffect(name) {}
-  void set_colors(const std::vector<AddressableColorWipeEffectColor> &colors) { this->colors_ = colors; }
+  explicit AddressableColorWipeEffect(const char *name) : AddressableLightEffect(name) {}
+  void set_colors(const std::initializer_list<AddressableColorWipeEffectColor> &colors) { this->colors_ = colors; }
   void set_add_led_interval(uint32_t add_led_interval) { this->add_led_interval_ = add_led_interval; }
   void set_reverse(bool reverse) { this->reverse_ = reverse; }
   void apply(AddressableLight &it, const Color &current_color) override {
@@ -155,7 +154,7 @@ class AddressableColorWipeEffect : public AddressableLightEffect {
   }
 
  protected:
-  std::vector<AddressableColorWipeEffectColor> colors_;
+  FixedVector<AddressableColorWipeEffectColor> colors_;
   size_t at_color_{0};
   uint32_t last_add_{0};
   uint32_t add_led_interval_{};
@@ -165,7 +164,7 @@ class AddressableColorWipeEffect : public AddressableLightEffect {
 
 class AddressableScanEffect : public AddressableLightEffect {
  public:
-  explicit AddressableScanEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableScanEffect(const char *name) : AddressableLightEffect(name) {}
   void set_move_interval(uint32_t move_interval) { this->move_interval_ = move_interval; }
   void set_scan_width(uint32_t scan_width) { this->scan_width_ = scan_width; }
   void apply(AddressableLight &it, const Color &current_color) override {
@@ -202,7 +201,7 @@ class AddressableScanEffect : public AddressableLightEffect {
 
 class AddressableTwinkleEffect : public AddressableLightEffect {
  public:
-  explicit AddressableTwinkleEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableTwinkleEffect(const char *name) : AddressableLightEffect(name) {}
   void apply(AddressableLight &addressable, const Color &current_color) override {
     const uint32_t now = millis();
     uint8_t pos_add = 0;
@@ -244,7 +243,7 @@ class AddressableTwinkleEffect : public AddressableLightEffect {
 
 class AddressableRandomTwinkleEffect : public AddressableLightEffect {
  public:
-  explicit AddressableRandomTwinkleEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableRandomTwinkleEffect(const char *name) : AddressableLightEffect(name) {}
   void apply(AddressableLight &it, const Color &current_color) override {
     const uint32_t now = millis();
     uint8_t pos_add = 0;
@@ -293,7 +292,7 @@ class AddressableRandomTwinkleEffect : public AddressableLightEffect {
 
 class AddressableFireworksEffect : public AddressableLightEffect {
  public:
-  explicit AddressableFireworksEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableFireworksEffect(const char *name) : AddressableLightEffect(name) {}
   void start() override {
     auto &it = *this->get_addressable_();
     it.all() = Color::BLACK;
@@ -342,7 +341,7 @@ class AddressableFireworksEffect : public AddressableLightEffect {
 
 class AddressableFlickerEffect : public AddressableLightEffect {
  public:
-  explicit AddressableFlickerEffect(const std::string &name) : AddressableLightEffect(name) {}
+  explicit AddressableFlickerEffect(const char *name) : AddressableLightEffect(name) {}
   void apply(AddressableLight &it, const Color &current_color) override {
     const uint32_t now = millis();
     const uint8_t intensity = this->intensity_;

esphome/components/light/base_light_effects.h

@@ -1,9 +1,9 @@
 #pragma once
 
 #include <utility>
-#include <vector>
 
 #include "esphome/core/automation.h"
+#include "esphome/core/helpers.h"
 #include "light_effect.h"
 
 namespace esphome {
@@ -17,7 +17,7 @@ inline static float random_cubic_float() {
 /// Pulse effect.
 class PulseLightEffect : public LightEffect {
  public:
-  explicit PulseLightEffect(const std::string &name) : LightEffect(name) {}
+  explicit PulseLightEffect(const char *name) : LightEffect(name) {}
 
   void apply() override {
     const uint32_t now = millis();
@@ -60,7 +60,7 @@ class PulseLightEffect : public LightEffect {
 /// Random effect. Sets random colors every 10 seconds and slowly transitions between them.
 class RandomLightEffect : public LightEffect {
  public:
-  explicit RandomLightEffect(const std::string &name) : LightEffect(name) {}
+  explicit RandomLightEffect(const char *name) : LightEffect(name) {}
 
   void apply() override {
     const uint32_t now = millis();
@@ -112,8 +112,8 @@ class RandomLightEffect : public LightEffect {
 
 class LambdaLightEffect : public LightEffect {
  public:
-  LambdaLightEffect(const std::string &name, std::function<void(bool initial_run)> f, uint32_t update_interval)
-      : LightEffect(name), f_(std::move(f)), update_interval_(update_interval) {}
+  LambdaLightEffect(const char *name, void (*f)(bool initial_run), uint32_t update_interval)
+      : LightEffect(name), f_(f), update_interval_(update_interval) {}
 
   void start() override { this->initial_run_ = true; }
   void apply() override {
@@ -130,7 +130,7 @@ class LambdaLightEffect : public LightEffect {
   uint32_t get_current_index() const { return this->get_index(); }
 
  protected:
-  std::function<void(bool initial_run)> f_;
+  void (*f_)(bool initial_run);
   uint32_t update_interval_;
   uint32_t last_run_{0};
   bool initial_run_;
@@ -138,7 +138,7 @@ class LambdaLightEffect : public LightEffect {
 
 class AutomationLightEffect : public LightEffect {
  public:
-  AutomationLightEffect(const std::string &name) : LightEffect(name) {}
+  AutomationLightEffect(const char *name) : LightEffect(name) {}
   void stop() override { this->trig_->stop_action(); }
   void apply() override {
     if (!this->trig_->is_action_running()) {
@@ -163,7 +163,7 @@ struct StrobeLightEffectColor {
 
 class StrobeLightEffect : public LightEffect {
  public:
-  explicit StrobeLightEffect(const std::string &name) : LightEffect(name) {}
+  explicit StrobeLightEffect(const char *name) : LightEffect(name) {}
   void apply() override {
     const uint32_t now = millis();
     if (now - this->last_switch_ < this->colors_[this->at_color_].duration)
@@ -188,17 +188,17 @@ class StrobeLightEffect : public LightEffect {
     this->last_switch_ = now;
   }
 
-  void set_colors(const std::vector<StrobeLightEffectColor> &colors) { this->colors_ = colors; }
+  void set_colors(const std::initializer_list<StrobeLightEffectColor> &colors) { this->colors_ = colors; }
 
  protected:
-  std::vector<StrobeLightEffectColor> colors_;
+  FixedVector<StrobeLightEffectColor> colors_;
   uint32_t last_switch_{0};
   size_t at_color_{0};
 };
 
 class FlickerLightEffect : public LightEffect {
  public:
-  explicit FlickerLightEffect(const std::string &name) : LightEffect(name) {}
+  explicit FlickerLightEffect(const char *name) : LightEffect(name) {}
 
   void apply() override {
     LightColorValues remote = this->state_->remote_values;

esphome/components/light/color_mode.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <cstdint>
+#include "esphome/core/finite_set_mask.h"
 
 namespace esphome {
 namespace light {
@@ -107,13 +108,9 @@ constexpr ColorModeHelper operator|(ColorModeHelper lhs, ColorMode rhs) {
 // Type alias for raw color mode bitmask values
 using color_mode_bitmask_t = uint16_t;
 
-// Constants for ColorMode count and bit range
-static constexpr int COLOR_MODE_COUNT = 10;                             // UNKNOWN through RGB_COLD_WARM_WHITE
-static constexpr int MAX_BIT_INDEX = sizeof(color_mode_bitmask_t) * 8;  // Number of bits in bitmask type
-
-// Compile-time array of all ColorMode values in declaration order
-// Bit positions (0-9) map directly to enum declaration order
-static constexpr ColorMode COLOR_MODES[COLOR_MODE_COUNT] = {
+// Lookup table for ColorMode bit mapping
+// This array defines the canonical order of color modes (bit 0-9)
+constexpr ColorMode COLOR_MODE_LOOKUP[] = {
     ColorMode::UNKNOWN,                // bit 0
     ColorMode::ON_OFF,                 // bit 1
     ColorMode::BRIGHTNESS,             // bit 2
@@ -126,33 +123,42 @@ static constexpr ColorMode COLOR_MODES[COLOR_MODE_COUNT] = {
     ColorMode::RGB_COLD_WARM_WHITE,    // bit 9
 };
 
-/// Map ColorMode enum values to bit positions (0-9)
-/// Bit positions follow the enum declaration order
-static constexpr int mode_to_bit(ColorMode mode) {
-  // Linear search through COLOR_MODES array
-  // Compiler optimizes this to efficient code since array is constexpr
-  for (int i = 0; i < COLOR_MODE_COUNT; ++i) {
-    if (COLOR_MODES[i] == mode)
-      return i;
-  }
-  return 0;
-}
+/// Bit mapping policy for ColorMode
+/// Uses lookup table for non-contiguous enum values
+struct ColorModeBitPolicy {
+  using mask_t = uint16_t;  // 10 bits requires uint16_t
+  static constexpr int MAX_BITS = sizeof(COLOR_MODE_LOOKUP) / sizeof(COLOR_MODE_LOOKUP[0]);
 
-/// Map bit positions (0-9) to ColorMode enum values
-/// Bit positions follow the enum declaration order
-static constexpr ColorMode bit_to_mode(int bit) {
-  // Direct lookup in COLOR_MODES array
-  return (bit >= 0 && bit < COLOR_MODE_COUNT) ? COLOR_MODES[bit] : ColorMode::UNKNOWN;
-}
+  static constexpr unsigned to_bit(ColorMode mode) {
+    // Linear search through lookup table
+    // Compiler optimizes this to efficient code since array is constexpr
+    for (int i = 0; i < MAX_BITS; ++i) {
+      if (COLOR_MODE_LOOKUP[i] == mode)
+        return i;
+    }
+    return 0;
+  }
+
+  static constexpr ColorMode from_bit(unsigned bit) {
+    return (bit < MAX_BITS) ? COLOR_MODE_LOOKUP[bit] : ColorMode::UNKNOWN;
+  }
+};
+
+// Type alias for ColorMode bitmask using policy-based design
+using ColorModeMask = FiniteSetMask<ColorMode, ColorModeBitPolicy>;
+
+// Number of ColorCapability enum values
+constexpr int COLOR_CAPABILITY_COUNT = 6;
 
 /// Helper to compute capability bitmask at compile time
-static constexpr color_mode_bitmask_t compute_capability_bitmask(ColorCapability capability) {
-  color_mode_bitmask_t mask = 0;
+constexpr uint16_t compute_capability_bitmask(ColorCapability capability) {
+  uint16_t mask = 0;
   uint8_t cap_bit = static_cast<uint8_t>(capability);
 
   // Check each ColorMode to see if it has this capability
-  for (int bit = 0; bit < COLOR_MODE_COUNT; ++bit) {
-    uint8_t mode_val = static_cast<uint8_t>(bit_to_mode(bit));
+  constexpr int color_mode_count = sizeof(COLOR_MODE_LOOKUP) / sizeof(COLOR_MODE_LOOKUP[0]);
+  for (int bit = 0; bit < color_mode_count; ++bit) {
+    uint8_t mode_val = static_cast<uint8_t>(COLOR_MODE_LOOKUP[bit]);
     if ((mode_val & cap_bit) != 0) {
       mask |= (1 << bit);
     }
@@ -160,12 +166,9 @@ static constexpr color_mode_bitmask_t compute_capability_bitmask(ColorCapability
   return mask;
 }
 
-// Number of ColorCapability enum values
-static constexpr int COLOR_CAPABILITY_COUNT = 6;
-
 /// Compile-time lookup table mapping ColorCapability to bitmask
 /// This array is computed at compile time using constexpr
-static constexpr color_mode_bitmask_t CAPABILITY_BITMASKS[] = {
+constexpr uint16_t CAPABILITY_BITMASKS[] = {
     compute_capability_bitmask(ColorCapability::ON_OFF),             // 1 << 0
     compute_capability_bitmask(ColorCapability::BRIGHTNESS),         // 1 << 1
     compute_capability_bitmask(ColorCapability::WHITE),              // 1 << 2
@@ -174,130 +177,38 @@ static constexpr color_mode_bitmask_t CAPABILITY_BITMASKS[] = {
     compute_capability_bitmask(ColorCapability::RGB),                // 1 << 5
 };
 
-/// Bitmask for storing a set of ColorMode values efficiently.
-/// Replaces std::set<ColorMode> to eliminate red-black tree overhead (~586 bytes).
-class ColorModeMask {
- public:
-  constexpr ColorModeMask() = default;
-
-  /// Support initializer list syntax: {ColorMode::RGB, ColorMode::WHITE}
-  constexpr ColorModeMask(std::initializer_list<ColorMode> modes) {
-    for (auto mode : modes) {
-      this->add(mode);
-    }
-  }
-
-  constexpr void add(ColorMode mode) { this->mask_ |= (1 << mode_to_bit(mode)); }
-
-  /// Add multiple modes at once using initializer list
-  constexpr void add(std::initializer_list<ColorMode> modes) {
-    for (auto mode : modes) {
-      this->add(mode);
-    }
-  }
-
-  constexpr bool contains(ColorMode mode) const { return (this->mask_ & (1 << mode_to_bit(mode))) != 0; }
-
-  constexpr size_t size() const {
-    // Count set bits using Brian Kernighan's algorithm
-    // More efficient for sparse bitmasks (typical case: 2-4 modes out of 10)
-    uint16_t n = this->mask_;
-    size_t count = 0;
-    while (n) {
-      n &= n - 1;  // Clear the least significant set bit
-      count++;
-    }
-    return count;
-  }
-
-  constexpr bool empty() const { return this->mask_ == 0; }
-
-  /// Iterator support for API encoding
-  class Iterator {
-   public:
-    using iterator_category = std::forward_iterator_tag;
-    using value_type = ColorMode;
-    using difference_type = std::ptrdiff_t;
-    using pointer = const ColorMode *;
-    using reference = ColorMode;
-
-    constexpr Iterator(color_mode_bitmask_t mask, int bit) : mask_(mask), bit_(bit) { advance_to_next_set_bit_(); }
-
-    constexpr ColorMode operator*() const { return bit_to_mode(bit_); }
-
-    constexpr Iterator &operator++() {
-      ++bit_;
-      advance_to_next_set_bit_();
-      return *this;
-    }
-
-    constexpr bool operator==(const Iterator &other) const { return bit_ == other.bit_; }
-
-    constexpr bool operator!=(const Iterator &other) const { return !(*this == other); }
-
-   private:
-    constexpr void advance_to_next_set_bit_() { bit_ = ColorModeMask::find_next_set_bit(mask_, bit_); }
-
-    color_mode_bitmask_t mask_;
-    int bit_;
-  };
-
-  constexpr Iterator begin() const { return Iterator(mask_, 0); }
-  constexpr Iterator end() const { return Iterator(mask_, MAX_BIT_INDEX); }
-
-  /// Get the raw bitmask value for API encoding
-  constexpr color_mode_bitmask_t get_mask() const { return this->mask_; }
-
-  /// Find the next set bit in a bitmask starting from a given position
-  /// Returns the bit position, or MAX_BIT_INDEX if no more bits are set
-  static constexpr int find_next_set_bit(color_mode_bitmask_t mask, int start_bit) {
-    int bit = start_bit;
-    while (bit < MAX_BIT_INDEX && !(mask & (1 << bit))) {
-      ++bit;
-    }
-    return bit;
-  }
-
-  /// Find the first set bit in a bitmask and return the corresponding ColorMode
-  /// Used for optimizing compute_color_mode_() intersection logic
-  static constexpr ColorMode first_mode_from_mask(color_mode_bitmask_t mask) {
-    return bit_to_mode(find_next_set_bit(mask, 0));
-  }
-
-  /// Check if a ColorMode is present in a raw bitmask value
-  /// Useful for checking intersection results without creating a temporary ColorModeMask
-  static constexpr bool mask_contains(color_mode_bitmask_t mask, ColorMode mode) {
-    return (mask & (1 << mode_to_bit(mode))) != 0;
-  }
-
-  /// Check if any mode in the bitmask has a specific capability
-  /// Used for checking if a light supports a capability (e.g., BRIGHTNESS, RGB)
-  bool has_capability(ColorCapability capability) const {
-    // Lookup the pre-computed bitmask for this capability and check intersection with our mask
-    // ColorCapability values: 1, 2, 4, 8, 16, 32 -> array indices: 0, 1, 2, 3, 4, 5
-    // We need to convert the power-of-2 value to an index
-    uint8_t cap_val = static_cast<uint8_t>(capability);
+/**
+ * @brief Helper function to convert a power-of-2 ColorCapability value to an array index for CAPABILITY_BITMASKS
+ * lookup.
+ *
+ * This function maps ColorCapability values (1, 2, 4, 8, 16, 32) to array indices (0, 1, 2, 3, 4, 5).
+ * Used to index into the CAPABILITY_BITMASKS lookup table.
+ *
+ * @param capability A ColorCapability enum value (must be a power of 2).
+ * @return The corresponding array index (0-based).
+ */
+inline int capability_to_index(ColorCapability capability) {
+  uint8_t cap_val = static_cast<uint8_t>(capability);
 #if defined(__GNUC__) || defined(__clang__)
-    // Use compiler intrinsic for efficient bit position lookup (O(1) vs O(log n))
-    int index = __builtin_ctz(cap_val);
+  // Use compiler intrinsic for efficient bit position lookup (O(1) vs O(log n))
+  return __builtin_ctz(cap_val);
 #else
-    // Fallback for compilers without __builtin_ctz
-    int index = 0;
-    while (cap_val > 1) {
-      cap_val >>= 1;
-      ++index;
-    }
-#endif
-    return (this->mask_ & CAPABILITY_BITMASKS[index]) != 0;
+  // Fallback for compilers without __builtin_ctz
+  int index = 0;
+  while (cap_val > 1) {
+    cap_val >>= 1;
+    ++index;
   }
+  return index;
+#endif
+}
 
- private:
-  // Using uint16_t instead of uint32_t for more efficient iteration (fewer bits to scan).
-  // Currently only 10 ColorMode values exist, so 16 bits is sufficient.
-  // Can be changed to uint32_t if more than 16 color modes are needed in the future.
-  // Note: Due to struct padding, uint16_t and uint32_t result in same LightTraits size (12 bytes).
-  color_mode_bitmask_t mask_{0};
-};
+/// Check if any mode in the bitmask has a specific capability
+/// Used for checking if a light supports a capability (e.g., BRIGHTNESS, RGB)
+inline bool has_capability(const ColorModeMask &mask, ColorCapability capability) {
+  // Lookup the pre-computed bitmask for this capability and check intersection with our mask
+  return (mask.get_mask() & CAPABILITY_BITMASKS[capability_to_index(capability)]) != 0;
+}
 
 }  // namespace light
 }  // namespace esphome

esphome/components/light/esp_color_correction.h

@@ -17,19 +17,19 @@ class ESPColorCorrection {
                  this->color_correct_blue(color.blue), this->color_correct_white(color.white));
   }
   inline uint8_t color_correct_red(uint8_t red) const ESPHOME_ALWAYS_INLINE {
-    uint8_t res = esp_scale8(esp_scale8(red, this->max_brightness_.red), this->local_brightness_);
+    uint8_t res = esp_scale8_twice(red, this->max_brightness_.red, this->local_brightness_);
     return this->gamma_table_[res];
   }
   inline uint8_t color_correct_green(uint8_t green) const ESPHOME_ALWAYS_INLINE {
-    uint8_t res = esp_scale8(esp_scale8(green, this->max_brightness_.green), this->local_brightness_);
+    uint8_t res = esp_scale8_twice(green, this->max_brightness_.green, this->local_brightness_);
     return this->gamma_table_[res];
   }
   inline uint8_t color_correct_blue(uint8_t blue) const ESPHOME_ALWAYS_INLINE {
-    uint8_t res = esp_scale8(esp_scale8(blue, this->max_brightness_.blue), this->local_brightness_);
+    uint8_t res = esp_scale8_twice(blue, this->max_brightness_.blue, this->local_brightness_);
     return this->gamma_table_[res];
   }
   inline uint8_t color_correct_white(uint8_t white) const ESPHOME_ALWAYS_INLINE {
-    uint8_t res = esp_scale8(esp_scale8(white, this->max_brightness_.white), this->local_brightness_);
+    uint8_t res = esp_scale8_twice(white, this->max_brightness_.white, this->local_brightness_);
     return this->gamma_table_[res];
   }
   inline Color color_uncorrect(Color color) const ESPHOME_ALWAYS_INLINE {

esphome/components/light/light_call.cpp

@@ -156,7 +156,7 @@ void LightCall::perform() {
     if (this->effect_ == 0u) {
       effect_s = "None";
     } else {
-      effect_s = this->parent_->effects_[this->effect_ - 1]->get_name().c_str();
+      effect_s = this->parent_->effects_[this->effect_ - 1]->get_name();
     }
 
     if (publish) {
@@ -437,7 +437,7 @@ ColorMode LightCall::compute_color_mode_() {
 
   // Use the preferred suitable mode.
   if (intersection != 0) {
-    ColorMode mode = ColorModeMask::first_mode_from_mask(intersection);
+    ColorMode mode = ColorModeMask::first_value_from_mask(intersection);
     ESP_LOGI(TAG, "'%s': color mode not specified; using %s", this->parent_->get_name().c_str(),
              LOG_STR_ARG(color_mode_to_human(mode)));
     return mode;
@@ -511,7 +511,7 @@ LightCall &LightCall::set_effect(const std::string &effect) {
   for (uint32_t i = 0; i < this->parent_->effects_.size(); i++) {
     LightEffect *e = this->parent_->effects_[i];
 
-    if (strcasecmp(effect.c_str(), e->get_name().c_str()) == 0) {
+    if (strcasecmp(effect.c_str(), e->get_name()) == 0) {
       this->set_effect(i + 1);
       found = true;
       break;

esphome/components/light/light_effect.h

@@ -1,7 +1,5 @@
 #pragma once
 
-#include <utility>
-
 #include "esphome/core/component.h"
 
 namespace esphome {
@@ -11,7 +9,7 @@ class LightState;
 
 class LightEffect {
  public:
-  explicit LightEffect(std::string name) : name_(std::move(name)) {}
+  explicit LightEffect(const char *name) : name_(name) {}
 
   /// Initialize this LightEffect. Will be called once after creation.
   virtual void start() {}
@@ -24,7 +22,11 @@ class LightEffect {
   /// Apply this effect. Use the provided state for starting transitions, ...
   virtual void apply() = 0;
 
-  const std::string &get_name() { return this->name_; }
+  /**
+   * Returns the name of this effect.
+   * The returned pointer is valid for the lifetime of the program and must not be freed.
+   */
+  const char *get_name() const { return this->name_; }
 
   /// Internal method called by the LightState when this light effect is registered in it.
   virtual void init() {}
@@ -47,7 +49,7 @@ class LightEffect {
 
  protected:
   LightState *state_{nullptr};
-  std::string name_;
+  const char *name_;
 
   /// Internal method to find this effect's index in the parent light's effect list.
   uint32_t get_index_in_parent_() const;

esphome/components/light/light_state.cpp

@@ -178,12 +178,9 @@ void LightState::set_restore_mode(LightRestoreMode restore_mode) { this->restore
 void LightState::set_initial_state(const LightStateRTCState &initial_state) { this->initial_state_ = initial_state; }
 bool LightState::supports_effects() { return !this->effects_.empty(); }
 const FixedVector<LightEffect *> &LightState::get_effects() const { return this->effects_; }
-void LightState::add_effects(const std::vector<LightEffect *> &effects) {
+void LightState::add_effects(const std::initializer_list<LightEffect *> &effects) {
   // Called once from Python codegen during setup with all effects from YAML config
-  this->effects_.init(effects.size());
-  for (auto *effect : effects) {
-    this->effects_.push_back(effect);
-  }
+  this->effects_ = effects;
 }
 
 void LightState::current_values_as_binary(bool *binary) { this->current_values.as_binary(binary); }