QMK
Keyboard firmware for Atmel AVR and ARM controllers
...Keyboards powered by QMK are Planck, Preonic, ErgoDox EZ, Clueboard, Cluepad, Gergo, Georgi, and Atreus. QMK is compatible with lots of other community-supported keyboards and projects. QMK is developed and maintained by Jack Humbert of OLKB with contributions from the community, and of course, Hasu.