Iiuc homebrew is creating a symlink? I think what I'm wondering is if the problem is that macOS is checking the actual location that the symlink resolves to, and that location might be changing after each upgrade?

Iiuc homebrew is creating a symlink?

I would certainly think so.

I do see a conversation about it in restic issues from 2018 here - restic/restic#2051 (comment). There might be more.

Hi @garethgeorge. Just wanted to check whether this is on any roadmap or planned by any chance? Just curious.

this is largely fixed on macOS. I'd add on however that you should actually only need to grant permissions (e.g. full disk access, etc) to backrest. I believe restic will inherit them.

Backrest will now try to use the system install of restic if it is up to date (e.g. this will often be the version provided by homebrew if you're using that package manager)

If it isn't, backrest now intelligently installs it's version of backrest at ~/.local/share/backrest/restic (with no version suffix).

You can check which binary backrest uses by checking the logs ~/.local/share/backrest/processlogs/ and looking at the logs from the last backrest startup.

So in 1.6.2 the logs indeed mention which version of restic is being used and in my case it is ~/.local/share/backrest/restic indeed. I had to give permission to it separately - both network and disk.

However I still see backrest being listed as /opt/homebrew/Cellar/backrest/1.6.2/bin/backrest so the next version of backrest will need permissions again. I have 3-4 backrest entires in Photos, iCloud, and Full Desk Access settings on Mac. Some of the older/residual ones I can remove, some I can't.

Then I removed Full Disk Access for every backrest entry and the backup still passed.