Most of it can be found just by exploring things at the holepunch repo. Here are a few of the links they shared.
https://github.com/holepunchto/pear
https://github.com/holepunchto/bare
https://github.com/holepunchto/libjs

Also here is an example app that they randomly built that they use to play music to each other while they work. Really fun a crazy idea, that one person plays the song and everyone else connects and listens in. Tossed together in a couple of hours apparently.
https://github.com/holepunchto/pear-radio