anchor.diff:    meta = with stdenv.lib; {
       description = "Electric Sheep, a distributed screen saver for evolving artificial organisms";
       homepage = http://electricsheep.org/;
  -    maintainers = maintainers.nand0p;
  +    maintainers = with maintainers; [ nand0p fpletz ];
       platforms = platforms.linux;
       license = licenses.gpl1;
     };
  
positive.code:   '';
  
    configureFlags = [
     "CPPFLAGS=-I${glee}/include/GL"
    ];
  
    preBuild = ''
  
negative.code: { stdenv, fetchFromGitHub, autoreconfHook, wxGTK30, libav, lua5_1, curl
  , libpng, xorg, pkgconfig, flam3, libgtop, boost, tinyxml, freeglut, mesa
  , glee }:
  
  stdenv.mkDerivation rec {
    name = "${pname}-${version}";
    pname = "electricsheep";
    version = "2.7b33-2017-02-04";
  
    src = fetchFromGitHub {
      owner = "scottdraves";
      repo = pname;
      rev = "12420cd40dfad8c32fb70b88f3d680d84f795c63";
      sha256 = "1zqry25h6p0y0rg2h8xxda007hx1xdvsgzmjg13xkc8l4zsp5wah";
    };
  
    nativeBuildInputs = [ autoreconfHook pkgconfig ];
  
    buildInputs = [
      wxGTK30 libav lua5_1 curl libpng xorg.libXrender
      flam3 libgtop boost tinyxml freeglut mesa glee
    ];
  
  