How can I version control pico-8 source code? It seems like the output is a binary (which technically can be checked in but would be difficult to diff).

How are others doing it?

If you save as foo.p8 instead of foo.p8.png it's a text-based format. I'm just storing that in git. The map, graphics, and sound areas are basically big hexadecimal blobs, but that's not too terrible, especially since they're only a couple kb.

Ah I see. Let me give that a try. Thanks!

Take a look at how I did version control for my pico8jam2 game: https://github.com/josefnpat/pico8jam2