anchor.diff:    name = "imagemagick-${version}";
     inherit (cfg) version;
   
  -  src = fetchurl {
  -    urls = [
  -      "mirror://imagemagick/releases/ImageMagick-${version}.tar.xz"
  -      # the original source above removes tarballs quickly
  -      "http://distfiles.macports.org/ImageMagick/ImageMagick-${version}.tar.xz"
  -      "https://bintray.com/homebrew/mirror/download_file?file_path=imagemagick-${version}.tar.xz"
  -    ];
  +  src = fetchFromGitHub {
  +    owner = "ImageMagick";
  +    repo = "ImageMagick";
  +    rev = cfg.version;
       inherit (cfg) sha256;
     };
   
  
positive.code: 
    cfg = {
      version = "7.0.7-22";
      sha256 = "12c48cfhc2a3zvhgxdywrfy8b4m2vx85vn2qj69iyni5x849xpj9";
      patches = [];
    };
  in
  
negative.code: { lib, stdenv, fetchFromGitHub, fetchpatch, pkgconfig, libtool
  , bzip2, zlib, libX11, libXext, libXt, fontconfig, freetype, ghostscript, libjpeg
  , lcms2, openexr, libpng, librsvg, libtiff, libxml2, openjpeg, libwebp
  , ApplicationServices
  