anchor.diff:  { lib, stdenv, fetchurl, dpkg
   , alsaLib, atk, cairo, cups, curl, dbus, expat, fontconfig, freetype, gdk-pixbuf, glib, glibc, gnome2, gnome3
   , gtk3, libappindicator-gtk3, libnotify, libpulseaudio, libsecret, libv4l, nspr, nss, pango, systemd, wrapGAppsHook, xorg
  -, at-spi2-atk, libuuid, at-spi2-core }:
  +, at-spi2-atk, libuuid, at-spi2-core, libdrm, mesa, libxkbcommon }:
   
   let
   
     # Please keep the version x.y.0.z and do not update to x.y.76.z because the
     # source of the latter disappears much faster.
  -  version = "8.68.0.100";
  +  version = "8.69.0.77";
   
     rpath = lib.makeLibraryPath [
       alsaLib
  
positive.code:           "https://mirror.cs.uchicago.edu/skype/pool/main/s/skypeforlinux/skypeforlinux_${version}_amd64.deb"
            "https://web.archive.org/web/https://repo.skype.com/deb/pool/main/s/skypeforlinux/skypeforlinux_${version}_amd64.deb"
          ];
          sha256 = "gHjgQRdNABO+R+fcDurHDAQtZpckIxLbODM6Txz+LH4=";
        }
      else
        throw "Skype for linux is not supported on ${stdenv.hostPlatform.system}";
  
negative.code:     pango
      stdenv.cc.cc
      systemd
  
      libv4l
      libdrm
      mesa
      libxkbcommon
      xorg.libxkbfile
      xorg.libX11
      xorg.libXcomposite
  