Open-source boards designed in KiCad by andr-line on GitHub, from 2 repositories. A board’s address here is its repository’s there.
andr-line/matrix_slim
This is the successor to my original Matrix keyboard, which was far from perfect. It aims to be as compact as possible while still providing enough keys to not have to re-learn to type.
andr-line/zmk-config-matrix
The files are adapted to me, the bottom keys for example are shifted by one since I always typed like that. Also one of my controllers was faulty so I had to add an additional pin that is not needed normaly (pin 101).