anchor.diff:  
       } // originalEtc // extraTrustedKeys // testRemote;
   
  -    services.dbus.packages = [ pkgs.fwupd ];
  +    services.dbus.packages = [ cfg.package ];
   
  -    services.udev.packages = [ pkgs.fwupd ];
  +    services.udev.packages = [ cfg.package ];
   
  -    systemd.packages = [ pkgs.fwupd ];
  +    systemd.packages = [ cfg.package ];
   
       systemd.tmpfiles.rules = [
         "d /var/lib/fwupd 0755 root root -"
  
positive.code:           <link xlink:href="https://github.com/hughsie/fwupd/blob/master/data/installed-tests/README.md">installed tests</link>.
          '';
        };
      };
    };
  
  
    ###### implementation
    config = mkIf cfg.enable {
      environment.systemPackages = [ pkgs.fwupd ];
  
      environment.etc = {
        "fwupd/daemon.conf" = {
  
negative.code:   cfg = config.services.fwupd;
    originalEtc =
      let
        mkEtcFile = n: nameValuePair n { source = "${cfg.package}/etc/${n}"; };
      in listToAttrs (map mkEtcFile cfg.package.filesInstalledToEtc);
    extraTrustedKeys =
      let
        mkName = p: "pki/fwupd/${baseNameOf (toString p)}";
  