anchor.diff:  stdenv.mkDerivation rec {
     name = "imagemagick-${version}";
     # Use stable patch releases, e.g. -9 or -10
  -  version = "6.9.2-10";
  +  version = "7.0.1-3";
   
     src = fetchurl {
  -    url = [
  -      "mirror://imagemagick/releases/ImageMagick-${version}.tar.xz"
  -      "mirror://imagemagick/ImageMagick-${version}.tar.xz"
  +    urls = map (n: "${n}/ImageMagick-${version}.tar.xz") [
  +      "mirror://imagemagick/releases"
  +      "mirror://imagemagick"
       ];
  -    sha256 = "0g01q8rygrf977d9rpixg1bhnavqfwzz30qpn7fj17yn8fx6ybys";
  +    allowHashOutput = false;
  +    sha256 = "4f5a39f145bb0326f811e0826a9216b8c449ee4485550aa8c2e7cfdaf26f08a0";
     };
   
     buildInputs = [
  
positive.code:     done
    '';
  
    enableParallelBuilding = true;
  
    meta = with stdenv.lib; {
      description = "A collection of tools and libraries for many image formats";
  
negative.code:       wkennington
      ];
      platforms = with platforms;
        x86_64-linux;
    };
  }
  