[daoistmonk]

Is this still true if you use flakes to build NixOS?

[oessessnex]

Yes, Nix doesn't actually ensure that the builds are deterministic. In fact it works just fine if they aren't. There are packages in nixpkgs that aren't reproducible: https://github.com/NixOS/nixpkgs/issues?q=is%3Aopen+is%3Aiss...