Matter Adaptive Lighting

Keeps Matter CCT lights at a sun-appropriate color temperature — warm below the horizon, cool at midday — while never touching on/off or brightness. Turn your lights on and off however you like (wall switch, Home Assistant, Alexa, Google); whenever they're on, they're the right temperature. Color temperature is even maintained while a light is off (Matter ExecuteIfOff), so it comes on correct.

It works by speaking the Home Assistant Matter Server WebSocket API and sending raw moveToColorTemperature cluster commands through the fabric HA already owns: no extra fabric on your devices, no commissioning, no persistent state, and HA's entity/automation layer is bypassed entirely.

The target curve is a pure function of solar elevation at your lat/lon (smoothstep between a warm floor and cool ceiling, interpolated in mired space), so mornings and evenings are symmetric and there is no timezone or schedule logic anywhere.

Running

As a local Home Assistant add-on (the intended deployment): copy matter-adaptive-lighting/ into /addons and install "Matter Adaptive Lighting" from Local add-ons. Configure lights and curve in the add-on options UI. See AGENTS.md for the exact deploy runbook.

For development, bare-metal with pyenv:

pyenv exec python -m venv .venv
.venv/bin/pip install -e "./matter-adaptive-lighting[dev]"
cp matter-adaptive-lighting/config.example.yaml config.yaml   # edit
.venv/bin/python -m matter_adaptive_lighting list   # find your node ids
.venv/bin/python -m matter_adaptive_lighting set 2700 --node 59
.venv/bin/python -m matter_adaptive_lighting run