anchor.diff:    meta = {
       description = "a scalable, high-performance, open source NoSQL database";
       homepage = http://www.mongodb.org;
  -    license = stdenv.lib.licenses.agpl3;
  +    license = licenses.agpl3;
   
  -    maintainers = [ stdenv.lib.maintainers.bluescreen303 ];
  -    platforms = stdenv.lib.platforms.unix;
  +    maintainers = with maintainers; [ bluescreen303 offline ];
  +    platforms = platforms.unix;
     };
   }
  
positive.code: { stdenv, fetchurl, scons, boost, gperftools, pcre, snappy }:
  
  let version = "2.6.4";
      system-libraries = [
  
negative.code:       # "v8"      -- mongo still bundles 3.12 and does not work with 3.15+
        # "stemmer" -- not nice to package yet (no versioning, no makefile, no shared libs)
        # "yaml"    -- it seems nixpkgs' yamlcpp (0.5.1) is problematic for mongo
      ] ++ optionals (!stdenv.isDarwin) [ "tcmalloc" ];
      system-lib-args = concatStringsSep " "
                          (map (lib: "--use-system-${lib}") system-libraries);
  
  in stdenv.mkDerivation rec {
    name = "mongodb-${version}";
  