I have my "home" as a master Syncthing folder, that I sync with a RPI3: https://syncthing.net/ I have it set up to keep a few revisions of every file.

Syncthing is not really meant for backup, but I really like that it just happens over the network, in the background, without further intervention. I am clumsy, lazy and not disciplined enough for other backup setups that require action (e.g. connecting the computer to something sometimes, manually triggering backups, etc...)