{ config, pkgs, ... }: with pkgs.lib; let configFile = ./xfs.conf; in { ###### interface options = { services.xfs = { enable = mkOption { type = types.bool; default = false; description = "Whether to enable the X Font Server."; }; }; }; ###### implementation config = mkIf config.services.xfs.enable { assertions = singleton { assertion = config.fonts.enableFontDir; message = "Please enable fonts.enableFontDir to use the X Font Server."; }; jobs.xfs = { description = "X Font Server"; startOn = "started networking"; exec = "${pkgs.xorg.xfs}/bin/xfs -config ${configFile}"; }; }; }