{ config, pkgs, lib, ... }: let cfg = config.my.server; in { imports = []; options.my.server = { enable = lib.mkEnableOption "server role"; }; config = lib.mkIf cfg.enable { services = { services.openssh.enable = true; }; programs = { }; networking.firewall = { allowedTCPPortRanges = [ { # ssh from = 22; to = 22; } ]; }; }; }