anchor.diff:    version = "${majorVersion}.${minorVersion}${minorVersionSuffix}";
     libPrefix = "pypy${majorVersion}";
     sitePackages = "site-packages";
  +
  +  pythonForPypy = python.withPackages (ppkgs: [ ppkgs.pycparser ]);
   
   in stdenv.mkDerivation rec {
       name = "pypy-${version}";
  
positive.code:       substituteInPlace "lib-python/2.7/lib-tk/Tix.py" --replace "os.environ.get('TIX_LIBRARY')" "os.environ.get('TIX_LIBRARY') or '${tix}/lib'"
      '';
  
      buildInputs = [ bzip2 openssl pkgconfig python libffi ncurses expat sqlite tk tcl xlibsWrapper libX11 makeWrapper gdbm db ]
        ++ (with pythonPackages; [ pycparser ])
        ++ stdenv.lib.optional (stdenv ? cc && stdenv.cc.libc != null) stdenv.cc.libc
        ++ stdenv.lib.optional zlibSupport zlib;
  
  
negative.code:     '';
  
      buildPhase = ''
        ${pythonForPypy.interpreter} rpython/bin/rpython --make-jobs="$NIX_BUILD_CORES" -Ojit --batch pypy/goal/targetpypystandalone.py --withmod-_minimal_curses --withmod-unicodedata --withmod-thread --withmod-bz2 --withmod-_multiprocessing
      '';
  
      setupHook = python-setup-hook sitePackages;
  