If you're comfortable at the terminal you might give restic a shot
Discussion
Will do, thanks!
Can't zap you :(
Try now
Nope. No zap icon on the note, and it's grayed out on your profile.
nostr:npub1s277u5rww60te98w9umz6p7pjcxuus96cegdsf4y978qcqvu8jtq88dsym
If restic appears fit for your purpose, then maybe BTRFS isn't the right tool anyway?
Borg Backup (another feature rich and popular backup tool) could also be the right thing for you then.