@zekjur Honestly, we should have that in the go builder by default. Perhaps even stdenv. We could then have a standard fakegit hook that returns the rev for the common rev checking commands which would work for any build process that does git integration via execve. Rev info for regular nixpkgs packages with non-flake input srcs would need to be locked along with version and src hash on update; ideally automatically and into a plain JSON file.