The http_request component's C++ API has been updated to use std::vector instead of std::map, std::list, and std::set for header handling. The get_response_headers() method (returning the full headers map) has been removed — use get_response_header(name) instead. Deprecated overloads using the old container types are provided until 2027.1.0.
This is a breaking change for external components in ESPHome 2026.3.0 and later.
ESP32 builds now exclude unused built-in IDF components by default to reduce compile time. This applies to both ESP-IDF and Arduino framework builds, since both use the ESP-IDF build system underneath. External components that use excluded IDF APIs (e.g., esp_vfs_fat.h, esp_http_client.h, esp_eth.h) must explicitly re-enable them via include_builtin_idf_component().
This is a breaking change for external components in ESPHome 2026.2.0 and later.
ESP32 Arduino builds now disable all Arduino libraries by default. ESPHome uses ESP-IDF APIs directly for WiFi, networking, and BLE, so most Arduino libraries were compiled and linked but never called. External components that use Arduino libraries must explicitly enable them via cg.add_library().
This is a breaking change for external components in ESPHome 2026.2.0 and later.
get_preference_hash() is deprecated. Use the new make_entity_preference<T>() method to create preference objects for storing entity state. This prepares for fixing preference hash collisions that cause entities to overwrite each other's stored data.
This is a breaking change for external components in ESPHome 2026.2.0 and later.
The set_retry, cancel_retry, and RetryResult APIs are deprecated. They will be removed in ESPHome 2026.8.0. Use set_timeout or set_interval instead.
This is a breaking change for external components in ESPHome 2026.2.0 and later.
WiFi and Logger components now use StaticVector for listener storage, eliminating heap allocation and STL overhead. External components that register listeners must now call request functions during code generation.
This is a breaking change for external components in ESPHome 2026.1.0 and later.
The scheduler's std::string-based APIs (set_timeout, set_interval, set_retry, defer, and their cancel counterparts) are now deprecated. Use const char* string literals or uint32_t numeric IDs instead.
This deprecation affects ESPHome 2026.1.0 and later, with removal planned for 2026.7.0.
The App.get_compilation_time() method is deprecated in favor of new constexpr methods. The compilation_time field in the native API now updates on every compile.
This is a breaking change for external components in ESPHome 2026.1.0 and later.
The callback signatures for text_sensor, text, and select components have been updated to reduce heap allocations. The select component callback signature has changed significantly.
This is a breaking change for external components in ESPHome 2026.1.0 and later.
ESP8266 builds now exclude unused Serial objects and waveform/PWM code by default. External components using these features must explicitly enable them.
This is a breaking change for external components in ESPHome 2026.1.0 and later.