anchor.diff:  
   in stdenv.mkDerivation rec {
     pname = "signal-desktop";
  -  version = "1.26.2";
  +  version = "1.27.1";
   
     src = fetchurl {
       url = "https://updates.signal.org/desktop/apt/pool/main/s/signal-desktop/signal-desktop_${version}_amd64.deb";
  -    sha256 = "08qx7k82x6ybqi3lln6ixzmdz4sr8yz8vfx0y408b85wjfc7ncjk";
  +    sha256 = "16fg60c5r7zcjs8ya6jk33l5kz8m21y9a1si3i0a2dvyaclz4a3q";
     };
   
     phases = [ "unpackPhase" "installPhase" ];
  
positive.code: , gnome2, gtk3, atk, at-spi2-atk, cairo, pango, gdk-pixbuf, glib, freetype, fontconfig
  , dbus, libX11, xorg, libXi, libXcursor, libXdamage, libXrandr, libXcomposite
  , libXext, libXfixes, libXrender, libXtst, libXScrnSaver, nss, nspr, alsaLib
  , cups, expat, udev, libnotify, libuuid
  # Unfortunately this also overwrites the UI language (not just the spell
  # checking language!):
  , hunspellDicts, spellcheckerLanguage ? null # E.g. "de_DE"
  
negative.code:     alsaLib
      atk
      at-spi2-atk
      at-spi2-core
      cairo
      cups
      dbus
  