anchor.diff:  
     nativeBuildInputs = [ pkgconfig ];
   
  -  buildInputs = [ zlib bzip2 curl lzma gettext ]
  +  buildInputs = [ zlib bzip2 curl lzma gettext libiconv ]
       ++ optionals sdlClient [ SDL SDL_mixer SDL_image SDL_ttf SDL_gfx freetype fluidsynth ]
       ++ optionals gtkClient [ gtk2 ]
       ++ optional server readline
  
positive.code: { stdenv, fetchurl, zlib, bzip2, pkgconfig, curl, lzma, gettext
  , sdlClient ? true, SDL, SDL_mixer, SDL_image, SDL_ttf, SDL_gfx, freetype, fluidsynth
  , gtkClient ? false, gtk2
  , server ? true, readline
  
negative.code:     license = licenses.gpl2;
  
      maintainers = with maintainers; [ pierron ];
      platforms = platforms.unix;
    };
  }
  