The retro refit keyboard used a Teensy to replace the original controller on a 386 "laptop".
Keyboard Maintainer: The QMK Community
Hardware Supported: Leading Edge D3 386 keyboard, Teensy
Make example for this keyboard (after setting up your build environment):
make handwired/retro_refit:default
See the build environment setup and the make instructions for more information. Brand new to QMK? Start with our Complete Newbs Guide.