[iends]

This is really cool.

As a software guy, how can I learn more about making PCBs (other than the linked blog)?

[mattclarkdotnet]

One way is to find something you want to make that has schematics available and then hack on it. For audio stuff https://sound-au.com has lots to start from. Use jlcpcb or similar and you can get small boards made for $1 each plus shipping