anchor.diff:      selenium_webdriver = g.selenium_webdriver_2_29_0;
       sinatra = g.sinatra_1_3_2;
       sprockets = g.sprockets_2_2_2;
  +    systemu = g.systemu_2_5_2;
       thor = g.thor_0_17_0;
       tilt = g.tilt_1_3_3;
       treetop = g.treetop_1_4_12;
       tzinfo = g.tzinfo_0_3_35;
  +    uuid = g.uuid_2_3_6;
       websocket = g.websocket_1_0_7;
       xml_simple = g.xml_simple_1_1_1;
     };
  -  gem_nix_args = [ ''autotest-rails'' ''buildr'' ''fakes3'' ''foreman'' ''nix'' ''rails'' ''rake'' ''rb-fsevent'' ''sass'' ''selenium-webdriver'' ''sinatra-1.3.2'' ];
  +  gem_nix_args = [ ''autotest-rails'' ''buildr'' ''fakes3'' ''foreman'' ''nix'' ''rails'' ''rake'' ''rb-fsevent'' ''sass'' ''selenium-webdriver'' ''sinatra-1.3.2'' ''uuid'' ];
     gems = {
       ZenTest_4_8_4 = {
         basename = ''ZenTest'';
  
positive.code:       requiredGems = [  ];
        sha256 = ''1cjwg6f9gj7w2n9916w12i1g97ngqqar44sc2r1x9ib5jicspb00'';
      };
      mail_2_4_4 = {
        basename = ''mail'';
        meta = {
  
negative.code:       requiredGems = [  ];
        sha256 = ''1c52ndjqcxpgxhlclbxf98clcpni216xk5zgrkcd4px84riyjbmp'';
      };
      uuid_2_3_6 = {
        basename = ''uuid'';
        meta = {
          description = ''UUID generator'';
          homepage = ''http://github.com/assaf/uuid'';
          longDescription = ''UUID generator for producing universally unique identifiers based on RFC 4122
  (http://www.ietf.org/rfc/rfc4122.txt).
  '';
        };
        name = ''uuid-2.3.6'';
        requiredGems = [ g.macaddr_1_6_1 ];
        sha256 = ''194xznnxncfgr0nx84l11gnafvkfzr1nj1swnwas75q0ld0ri2l8'';
      };
      websocket_1_0_7 = {
        basename = ''websocket'';
        meta = {
  