QMK (Quantum Mechanical Keyboard) is an open source community centered around developing computer input devices. The community encompasses all sorts of input devices, such as keyboards, mice, and MIDI devices. A core group of collaborators maintains QMK Firmware, QMK Configurator, QMK Toolbox, qmk.fm, and this documentation with the help of community members like you.
See also https://github.com/mihaiolteanu/mugur
, an Emacs program to help configuring a QMK keyboard.