Acknowledgments
Stands on people who already did the reverse-engineering Apple wouldn't.
KBPulse
github.com/EthanRDoesMC/KBPulse
Keyboard brightness via CoreBrightness on M1+. The reason LEDFlash can spring the keyboard backlight at all on Apple Silicon. Without this work the keyboard-flash output would be Caps Lock only.
spank
IOKit patterns and hardware-interaction approaches. The conventions for talking to the SPU HID device safely from userland Swift are downstream of this.
apple-silicon-accelerometer
github.com/olvvier/apple-silicon-accelerometer
Proved the BMI286 was accessible at all. Without this we would not be here.
mac-hardware-toys
github.com/pirate/mac-hardware-toys
Keyboard-brightness wrapping and system-level integration patterns. Reference for Real/Mock seam shape on private CoreBrightness.
macbook-lighter
github.com/harttle/macbook-lighter
Brightness-daemon design and light-sensing approaches. The shape of AmbientLightSource and the SPU usage-7 subscriber owe its design to this prior work.
This app only exists because they did the work first. Pay them attention.