anchor.diff:      railties = g.railties_3_1_3;
       rake = g.rake_0_9_2_2;
       rdoc = g.rdoc_3_11;
  +    sass = g.sass_3_1_11;
       sprockets = g.sprockets_2_0_3;
       thor = g.thor_0_14_6;
       tilt = g.tilt_1_3_3;
       treetop = g.treetop_1_4_10;
       tzinfo = g.tzinfo_0_3_31;
     };
  -  gem_nix_args = [ ''nix'' ''rails'' ''rake'' ];
  +  gem_nix_args = [ ''nix'' ''rails'' ''rake'' ''sass'' ];
     gems = {
       actionmailer_3_1_3 = {
         basename = ''actionmailer'';
  
positive.code:     erubis = g.erubis_2_7_0;
      hike = g.hike_1_2_1;
      i18n = g.i18n_0_6_0;
      json = g.json_1_6_1;
      mail = g.mail_2_3_0;
      mime_types = g.mime_types_1_17_2;
      multi_json = g.multi_json_1_0_3;
      nix = g.nix_0_1_1;
      polyglot = g.polyglot_0_3_3;
      rack = g.rack_1_3_5;
  
negative.code:       requiredGems = [  ];
        sha256 = ''1pgmfhmh2wv409g7kla30mkp8jpslvp25vcmmim1figl87wpn3j0'';
      };
      json_1_6_3 = {
        basename = ''json'';
        meta = {
          description = ''JSON Implementation for Ruby'';
          homepage = ''http://flori.github.com/json'';
          longDescription = ''This is a JSON implementation as a Ruby extension in C.'';
        };
        name = ''json-1.6.3'';
        requiredGems = [  ];
        sha256 = ''0bcl6r04b0r5c0n1y47c7d29r50rl2rzd2hsc23832kgfrc1488m'';
      };
      mail_2_3_0 = {
        basename = ''mail'';
  