anchor.diff:  { stdenv, fetchurl, makeWrapper, zlib, glib, libpng, freetype, xorg
   , fontconfig, xlibs, qt5, xkeyboard_config, alsaLib, pulseaudio ? null
  -, libredirect
  +, libredirect, quazip
   }:
   
   let
  
positive.code:   installPhase =
      ''
        # Delete unecessary libraries - these are provided by nixos.
        rm libQt*.so.*
        rm qt.conf
  
        # Install files.
  
negative.code:       ln -s $out/lib/teamspeak/ts3client $out/bin/ts3client
  
        wrapProgram $out/bin/ts3client \
          --set LD_PRELOAD "${libredirect}/lib/libredirect.so:${quazip}/lib/libquazip.so" \
          --set QT_PLUGIN_PATH "$out/lib/teamspeak/platforms" \
          --set NIX_REDIRECTS /usr/share/X11/xkb=${xkeyboard_config}/share/X11/xkb
      '';
  