The logger::LogListener abstract class has been removed. Components that receive log messages must now register a callback with logger::global_logger->add_log_callback(instance, callback) instead of inheriting from LogListener and calling add_log_listener().
This is a breaking change for external components in ESPHome 2026.3.0 and later.
All register_action() calls now require an explicit synchronous=True or synchronous=False parameter. This enables the StringRef optimization for synchronous actions (zero-copy string argument passing) while ensuring asynchronous actions safely use owning std::string to prevent dangling references. Existing external components will continue to work but will see a warning at config time until updated.
This is a breaking change for external components in ESPHome 2026.3.0 and later.
The RP2040 platform has been updated to arduino-pico 5.5.0 (from 3.9.4), pico-sdk 2.1.0 (from 1.5.1), and GCC 14 (from GCC 12). Several hardware register names, API functions, and macros have changed. External components targeting RP2040 may need updates.
This is a breaking change for external components in ESPHome 2026.3.0 and later.
The socket::Socket and socket::ListenSocket types have been changed from virtual base classes to concrete type aliases. Listen sockets now use the ListenSocket type instead of Socket. These changes save 1,020–3,228 bytes of flash across platforms by eliminating virtual dispatch overhead.
This is a breaking change for external components in ESPHome 2026.3.0 and later.
The UARTComponent::flush() method return type has changed from void to FlushResult. External components that subclass UARTComponent and override flush() must update their override to return a FlushResult value.
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.