anchor.diff:  
     src = fetchurl {
       url = "https://updates.signal.org/desktop/apt/pool/main/s/signal-desktop/signal-desktop_${version}_amd64.deb";
  -    sha256 = "19vsv7jv30xvfgq1nr3091b6x4agymy9afpy9r9mxzgn0xfb0ap9";
  +    sha256 = "1ggblpw2xxhm78sqadswcv0314zagksj34z8pywjnr8h9zkcyiap";
     };
   
     nativeBuildInputs = [
  
positive.code:       else "");
  in stdenv.mkDerivation rec {
    pname = "signal-desktop";
    version = "1.31.0"; # Please backport all updates to the stable channel.
    # All releases have a limited lifetime and "expire" 90 days after the release.
    # When releases "expire" the application becomes unusable until an update is
    # applied. The expiration date for the current release can be extracted with:
  
negative.code:       Signal Desktop is an Electron application that links with your
        "Signal Android" or "Signal iOS" app.
      '';
      homepage    = "https://signal.org/";
      changelog   = "https://github.com/signalapp/Signal-Desktop/releases/tag/v${version}";
      license     = lib.licenses.gpl3;
      maintainers = with lib.maintainers; [ ixmatus primeos equirosa ];
      platforms   = [ "x86_64-linux" ];
  