anchor.diff:        fasteners coverage pywatchman futures cffi
       ];
   
  +    # Teach pants about where its native engine lives.
  +    # TODO: there's probably a better way to teach it this without having it "download"
  +    # from a local file: URL to its cache, but I don't know how and this seems to work.
  +    postFixup = ''
  +      mkdir -p $out/etc
  +      cat >$out/etc/pantsrc <<EOF
  +      [binaries]
  +      baseurls: [ 'file://${pants13-native-engine}' ]
  +      EOF
  +    '';
  +
       meta = {
         description = "A build system for software projects in a variety of languages";
         homepage    = "http://www.pantsbuild.org/";
  
positive.code:      maintainers = with maintainers; [ copumpkin ];
      };
    };
  in {
    pants =
      pythonPackages.buildPythonPackage rec {
  
negative.code: 
    pants13-pre = buildPythonApplication rec {
      pname   = "pantsbuild.pants";
      version = pants13-version;
      name    = "${pname}-${version}";
  
      src = fetchPypi {
  