@octorine @PuercoPop @civodul That's correct. It looks like this in practice: https://github.com/NinjaTrappeur/nixpkgs/blob/23586a2787da6d0b91c2abd8f3c6cc7bfa70d950/pkgs/tools/admin/coldsnap/default.nix#L18

But again, it's a tradeoff. You're giving cargo full control of part of the build graph and become partially blind to the dependencies.