anchor.diff:    perlDataPage = import ../development/perl-modules/generic perl {
       name = "Data-Page-2.01";
       src = fetchurl {
  -      url = http://search.cpan.org/CPAN/authors/id/L/LB/LBROCARD/Data-Page-2.01.tar.gz;
  +      url = mirror://cpan/authors/id/L/LB/LBROCARD/Data-Page-2.01.tar.gz;
         sha256 = "0mvhlid9qx9yd94rgr4lfz9kvflimc1dzcah0x7q5disw39aqrzr";
       };
       propagatedBuildInputs = [perlTestException perlClassAccessorChained];
  
positive.code:   perlTreeDAGNode = import ../development/perl-modules/generic perl {
      name = "Tree-DAG_Node-1.06";
      src = fetchurl {
        url = http://search.cpan.org/CPAN/authors/id/C/CO/COGENT/Tree-DAG_Node-1.06.tar.gz;
        sha256 = "0anvwfh4vqj41ipq52p65sqlvw3rvm6cla5hbws13gyk9mvp09ah";
      };
    };
  
negative.code:   perlCarpClan = import ../development/perl-modules/generic perl {
      name = "Carp-Clan-6.00";
      src = fetchurl {
        url = mirror://cpan/authors/id/J/JJ/JJORE/Carp-Clan-6.00.tar.gz;
        sha256 = "0lbin4i0vzagcwkywpd5x4gz3a4ira4yn5g5v1ip0pbpyqnjk15h";
      };
      propagatedBuildInputs = [perlTestException];
  