I've mixed 2 design from:
https://github.com/tshort/dactyl-keyboard
https://github.com/mensikv/VMs-macro-keyboard
12 mechanical programmable keys and a rotary encoder.
Follow vmensik's instruction.
At this link the modified code:
https://github.com/pagibe/12_pro_micro
It's thinked for video editing but could be useful for a lot of application.
Let me know if it's useful and ergonomic!