prepare configuration for server use

modules/server/default.nix

@@ -0,0 +1,33 @@
+{
+  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;
+        }
+      ];
+    };
+  };
+}