Eh... why do we try to be magical? When you claim to depend on a package that's actually a file, Nix treats it as a build hook and tries to execute it: https://github.com/NixOS/nixpkgs/commit/b23dbb1a5dffbfa3abb47fcd0f1579ac2e6f29fc

So, adding extraneous srcs to buildInputs breaks your build instead of doing nothing.

#nixos