Xiaomi MiThermomether
ATC_MiThermometer Telink Flasher for Mi Thermostat
ESPHome: Xiaomi Mijia BLE Sensors
Arduino version adapted to standalone C code is available on Blog di Bernardino (Dino) Ciuffetti:
C version
Compiled binaries for Raspberry can be downloaded from nettemp project: modules/sensors/i2c/TSL2561
Other projects:
Node JS interface
TSL2561-Arduino-Library