Personally, I've had some issues with Kopia.

I found their explanation here:

https://github.com/kopia/kopia/issues/1764

https://github.com/kopia/kopia/issues/544

Still not solved after many years :(

Now I use Borg + Restic and I am happy

+ GUI for Restic https://github.com/garethgeorge/backrest

+ GUI for Borg https://github.com/borgbase/vorta

Previous discussions:

- https://news.ycombinator.com/item?id=37526477 (2023-09-15, 326 points)

- https://news.ycombinator.com/item?id=35104406 (2023-03-11, 73 points)

When I looked at the CDC-based incremental backup space, Kopia seemed like a better Restic and the best of the bunch. At least as far as correctness and reliability goes.

I read the docs, but wasn’t really sure that sets it apart from Duplicacy or Restic?

No ZFS snapshots integration, right?

looks like an interesting alternative to borg backup