anchor.diff:    };
   
     libXext = attrs: attrs // {
  -    outputs = [ "out" "dev" "doc" ];
  +    outputs = [ "out" "dev" "man" "doc" ];
       propagatedBuildInputs = [ xorg.xproto xorg.libXau ];
       preConfigure = setMalloc0ReturnsNullCrossCompiling;
     };
  
positive.code:   };
  
    libXi = attrs: attrs // {
      outputs = [ "out" "dev" "doc" ];
      propagatedBuildInputs = [ xorg.libXfixes ];
    };
  
  
negative.code:   libxcb = attrs : attrs // {
      nativeBuildInputs = [ args.python ];
      configureFlags = "--enable-xkb --enable-xinput";
      outputs = [ "out" "dev" "man" "doc" ];
    };
  
    xcbproto = attrs : attrs // {
  