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
Syncthing is great but I really wish for a syncthing-lite you could deploy and configure easily.
The version we have today is really suffering from a lot of legacy.
I remember they are working on a big v2 with a revamp of the API which is a mess but they had to give up on getting rid on that horrible XML config file because it was too much work.
Be aware they also recently silently disabled the sync of symlinks on the android build, what can cause a lot of bad surprises.
They did define some specs of their protocols [0] but i haven't seen a alternative implementation yet.