This is nice. Kudos for using Bonjour/Zeroconf, which I do too for everything that needs self-discovery.
it just uses your local wifi. run it on your machines, tell them to trust each other, and you're set. and if you manage to edit the same file at once, it handles the conflict and saves both copies.
for anyone who just wants to get files from point a to b without the headache. hope it makes your life a bit less annoying.
github: https://github.com/sirbread/sink binary: https://github.com/sirbread/sink/releases/tag/v0.1