anchor.diff:      ] ++ optionals buildClient [
         "-DOpenGL_GL_PREFERENCE=GLVND"
       ];
  -    
  +
       NIX_CFLAGS_COMPILE = "-DluaL_reg=luaL_Reg"; # needed since luajit-2.1.0-beta3
   
       nativeBuildInputs = [ cmake doxygen graphviz ];
  
positive.code:   };
  
    v5 = {
      version = "5.2.0";
      sha256 = "0pj9hkxwc1vzng2khbixi79557sbawf6mqkzl589jciyqa7jqkv1";
      dataSha256 = "1kjz7x3xiqqnpyrd6339a139pbdxx31c4qpg8pmns410hsm8i358";
    };
  
  in {
  
negative.code:     buildInputs = [
        irrlicht luajit jsoncpp gettext freetype sqlite curl bzip2 ncurses
        gmp libspatialindex
      ] ++ optionals stdenv.isDarwin [
        libiconv OpenGL OpenAL Carbon Cocoa
      ] ++ optionals buildClient [
        libpng libjpeg libGLU libGL openal libogg libvorbis xorg.libX11 libXxf86vm
  