nixpkgs.nix

import (fetchTarball {
  # nixos unstable from 2019-09-30
  url = https://github.com/NixOS/nixpkgs/archive/593867effb2806e9d2f28f326bbab75d53159ac5.tar.gz;
  sha256 = "1jivsjg441sdzmn81p146cp5r3y28qwyyh3vwyijfp0ylvp5sggg";
})