anchor.diff:        md5 = "c5df008669d17dd6eeb5e2042d5e136f";
       };
   
  -    buildInputs = [ cffi pycparser mock pytest py ];
  +    buildInputs = [ pycparser mock pytest py ] ++ optionals (!isPyPy) [ cffi ];
   
       meta = {
         maintainers = [ stdenv.lib.maintainers.iElectric ];
  
positive.code:     };
  
      buildInputs = [ pkgs.btrfsProgs ];
      propagatedBuildInputs = with pkgs; [ contextlib2 sqlalchemy9 pyxdg pycparser cffi alembic ];
  
      meta = {
        description = "Deduplication for Btrfs";
  
negative.code:       export DYLD_LIBRARY_PATH="${pkgs.libgit2}/lib"
      '' else "" );
  
      propagatedBuildInputs = [ pkgs.libgit2 ] ++ optionals (!isPyPy) [ cffi ];
  
      preCheck = ''
        # disable tests that require networking
  