|Borg is a very capable backup tool, I use on all my servers. It does the advanced stuff that's needed for backups today. Like encryption, deduplication, compression and validation.|
There was no complete GUI for it, so I made one. It's intentionally built on a boring stack to keep it simple and basic. It should just sit there, do backups and let you know when something breaks.
It's also open source because I wouldn't trust a backup tool that isn't. Development is still early, but it should be stable enough for regular use. Bugreports, feature ideas and PRs welcome. Link:
You can back up to any SSH account that has Borg installed, or try my hosted Borg repo service, which also does neat stuff like alerting of stale backups, as well as isolated- and append-only repos.