Yes, resistance is futile! Borg is a descendant of attic with is a descendant of obnam. Development of the latter has ceased, so I needed a new victim. borg is a compressing, deduplicating, file based backup program which does more or less the same than obnam.
Despite its lineage borg is a bit different. It kinda does not work via ssh, only by FUSE and a sshfs-usermount, which is quite a bad choice, as I learned. It’s much faster if you run borg on the source, i.e. “where the data is” and transfer the result to the backup repository. Thinking about it, that’s not much of a surprise.
If you use sshfs, the destination has to pull all data for deduplication and compression, so no bandwidth is spared. If you run a borg server and only send the result of deduplication and compression over the wire, it’s much faster, what a surprise! So, always run borg at the source!