import (fetchTarball {
  url = "https://github.com/NixOS/nixpkgs/archive/4cd2cb43fb3a87f48c1e10bb65aee99d8f24cb9d.tar.gz";
  sha256 = "1d6rmq67kdg5gmk94wx2774qw89nvbhy6g1f2lms3c9ph37hways";
})