Use case You have to run your program on a remote server. However your favourite editor with your favourite configuration isn’t available over SSH. Or its over-SSH mode is very slow (looking at you, TRAMP). Also, you’d like to work online sometimes.
Unison is like Dropbox but without an intermediary server.
Setting it up First, you need to have two1 directories, one in your local machine and one in your remote machine, that will be synchronised.