anchor.diff:  stdenv.mkDerivation rec {
     name = "${prefix}-${version}";
   
  -  src = fetchurl {
  -    name = "grub-2.02-beta2.tar.xz";
  -    url = "http://alpha.gnu.org/gnu/grub/grub-2.02~beta2.tar.xz";
  -    sha256 = "13a13fhc0wf473dn73zhga15mjvkg6vqp4h25dxg4n7am2r05izn";
  +  src = fetchgit {
  +    url = "git://git.savannah.gnu.org/grub.git";
  +    rev = "1de3a48098053aaebd35232bd73e3ce3f3fdf51c";
  +    sha256 = "0d1953nmi251czkm1dmd7vnm3iz2rkqbznlp6ph33va0d7kw1kfc";
     };
   
     nativeBuildInputs = [ autogen flex bison python autoconf automake ];
  
positive.code: 
    canEfi = any (system: stdenv.system == system) (mapAttrsToList (name: _: name) efiSystems);
  
    prefix = "grub${if efiSupport then "-efi" else ""}";
  
    version = "2.02-beta2";
  
    unifont_bdf = fetchurl {
      url = "http://unifoundry.com/unifont-5.1.20080820.bdf.gz";
  
negative.code: { stdenv, fetchurl, fetchgit, autogen, flex, bison, python, autoconf, automake
  , gettext, ncurses, libusb, freetype, qemu, devicemapper
  , linuxPackages ? null
  , efiSupport ? false
  