Yes, it would be nice to have some core features at the fs layer. Something similar to zfs or btfs would be the best in my opinion, but both of those are not an option on linux in the near future. And 2 benefits of rdiff-backup (over HFS+) are that it works on any filesystem and that it only saves binary deltas rather than complete files when something changes, therefore saving a lot of space if a small portion of a 10gb file changes.

@Bruno

Right now the prototype daemon I have does support changing the root of the backup, as well as specifying include and exclude folders, so yes. However, it would not be in the simple interface, it would require some navigation into an advanced mode.

@Alex

Looks interesting, I hadn’t heard of that project before. You’re right, it seems to be more focused on backing up settings for migration. While that has its place, I don’t think that’s what TimeVault should strive to be.

I’m not sure if the awnser isn’t to do what apple did and insert directory hard links with recursion detection into the fs layer though.

Is there a reason for abandoning the snapshot-based architecture used in timevault?

I think a lot of the ideas you describe are excellent and I feel that a user-friendly backup tool for KDE would be a tremendous addition. I thought I would just mention one previous effort (now defunct?) led by Ivan Cukic, which was focused more on backing up and porting application configurations: Kamion. You might find some of the ideas from this project interesting.

http://kamion2.sourceforge.net/