anchor.diff:      sha256 = "1ska0z15sjhyfi860rjazz9ya1gxbf5c0h8dfqwz88h7fccd22b4";
     };
   
  -  nativeBuildInputs = [ makeWrapper ];
  +  nativeBuildInputs = [ makeWrapper installShellFiles ];
   
     checkInputs = [ subversion git breezy ];
   
  
positive.code: { lib, fetchurl, makeWrapper
  , pypy2Packages
  , cvs, subversion, git, breezy
  }:
  
  pypy2Packages.buildPythonApplication  rec {
  
negative.code:     for i in bzr svn git; do
        wrapProgram $out/bin/cvs2$i \
            --prefix PATH : "${lib.makeBinPath [ cvs ]}"
        $out/bin/cvs2$i --man > csv2$i.1
        installManPage csv2$i.1
      done
    '';
  
  