anchor.diff:  
     configureFlags = [
       "--enable-systemd"
  -    "--enable-nix"
       "--disable-dummy"
       "--disable-cron"
       "--disable-introspection"
  
positive.code:     "--with-dbus-sys=$(out)/etc/dbus-1/system.d"
      "--with-systemdsystemunitdir=$(out)/lib/systemd/system/"
    ]
    ++ lib.optional (!enableBashCompletion) "--disable-bash-completion"
    ++ lib.optional (!enableCommandNotFound) "--disable-command-not-found";
  
  
negative.code: { stdenv, fetchFromGitHub, lib
  , intltool, glib, pkgconfig, polkit, python, sqlite, systemd
  , gobjectIntrospection, vala_0_23, gtk_doc, autoreconfHook, autoconf-archive
  # TODO: set enableNixBackend to true, as soon as it builds
  , nix, enableNixBackend ? false, boost
  , enableCommandNotFound ? false
  , enableBashCompletion ? false, bash-completion ? null }:
  
  