import (fetchTarball {
  url = "https://github.com/NixOS/nixpkgs/archive/807ca93fadd5197c2260490de0c76e500562dc05.tar.gz";
  sha256 = "10yq8bnls77fh3pk5chkkb1sv5lbdgyk1rr2v9xn71rr1k2x563p";
})