anchor.diff:    perlClassAccessorChained = import ../development/perl-modules/generic perl {
       name = "Class-Accessor-Chained-0.01";
       src = fetchurl {
  -      url = http://search.cpan.org/CPAN/authors/id/R/RC/RCLAMP/Class-Accessor-Chained-0.01.tar.gz;
  +      url = mirror://cpan/authors/id/R/RC/RCLAMP/Class-Accessor-Chained-0.01.tar.gz;
         sha256 = "1lilrjy1s0q5hyr0888kf0ifxjyl2iyk4vxil4jsv0sgh39lkgx5";
       };
       propagatedBuildInputs = [perlClassAccessor];
  
positive.code:   perlClassC3Componentised = import ../development/perl-modules/generic perl {
      name = "Class-C3-Componentised-1.0003";
      src = fetchurl {
        url = http://search.cpan.org/CPAN/authors/id/A/AS/ASH/Class-C3-Componentised-1.0003.tar.gz;
        sha256 = "0lbhzz18lfp2xa8h5cmhfnqbqzhvpx4jkvga9gzwiv9ppbdpzqdp";
      };
      propagatedBuildInputs = [perlClassC3 perlClassInspector perlTestException];
  
negative.code:   perlCatalystPluginHTMLWidget = import ../development/perl-modules/generic perl {
      name = "Catalyst-Plugin-HTML-Widget-1.1";
      src = fetchurl {
        url = mirror://cpan/authors/id/S/SR/SRI/Catalyst-Plugin-HTML-Widget-1.1.tar.gz;
        sha256 = "1zzyfhmzlqvbwk2w930k3mqk8z1lzhrja9ynx9yfq5gmc8qqg95l";
      };
      propagatedBuildInputs = [perlCatalystRuntime perlHTMLWidget];
  