Individually addressable LED strips — hundreds of tiny LEDs, each capable of its own color and brightness — controlled by ESP8266 and ESP32 microcontrollers running WLED firmware, integrated into Apple HomeKit and Home Assistant. The office lighting responds to time of day, calendar events, and sensor data. It sounds like overkill for an office, and it is. But it’s also a complete, working IoT system built from commodity hardware and open-source software — the same architecture pattern that shows up in commercial smart-building projects, just at a scale where I can solder the connections myself.