import (
  builtins.fetchTarball {
    url = "https://github.com/nixos/nixpkgs/archive/ece829033b7b8f4e81261fef5427144df4147bc4.tar.gz";
    sha256 = "07n91k3d9i9pym8npsszha9mnvg4d1r0l0ldnhk4g8sx15vv1br5";
  }
)