anchor.diff:  assert useAlsa -> alsaOss != null;
   
   let
  -  icon = fetchurl {
  -    url = "https://hydra-media.cursecdn.com/minecraft.gamepedia.com/c/c5/Grass.png";
  -    sha256 = "438c0f63e379e92af1b5b2e06cc5e3365ee272810af65ebc102304bce4fa8c4b";
  -  };
  -
     desktopItem = makeDesktopItem {
       name = "minecraft";
       exec = "minecraft";
  -    icon = "${icon}";
  +    icon = "minecraft";
       comment = "A sandbox-building game";
       desktopName = "Minecraft";
       genericName = "minecraft";
  
positive.code: { stdenv, fetchurl, makeDesktopItem
  , jre, libX11, libXext, libXcursor, libXrandr, libXxf86vm
  , mesa, openal
  , useAlsa ? false, alsaOss ? null }:
  with stdenv.lib;
  
negative.code: 
      mkdir -p $out/share/applications
      ln -s ${desktopItem}/share/applications/* $out/share/applications/
  
      ${openjdk}/bin/jar xf $out/minecraft.jar favicon.png
      install -D favicon.png $out/share/icons/hicolor/32x32/apps/minecraft.png
    '';
  
    meta = {
  