That’s impressive, I’ll have to give borg a go. Thanks for pulling that up.

I didn’t know it worked like that, so I was thinking file types matter. Like diff (often used with git) has magic based on code-like text files but wouldn’t be efficient at incrementally backing up an encrypted file.

I’m curious how they handle “frame shift” like if a file has a few bytes added in the front, middle, or end. I guess the first time a file appears, Borg indexes the chunks or something.