It’s a bit off topic but since many users will be interested in it (including myself), it’s good to refer to the project.
The current GitHub page is still very limited. It doesn’t show what can be controlled and how the hardware addition should be installed. Do I understand correctly it is soldered on somewhere?
If the documentation is clear, I’ll link to it in the top post.
Yes agree. I just dumped what I did into the GitHub. There is work in making the board, but I picked components that are suitable for hand soldering. Once the board is made and programmed, it slips onto the zappi pins. No soldering required. The pins just need to be extended, which is easy to do. Let me work on the documentation in the next while.
Is this repo still up or private? As I dont see anything except a 404 on the linked repo?
Hi. I am updating the code and board to make it more robust. In about a week or so I’ll put it back up 
This is what I see too… Let me know if you find it, I’d much prefer some sort of local control.