Add swaylock

modules/services/swaylock.nix

@@ -0,0 +1,17 @@
+{ config, pkgs, lib, ... }:
+with lib;
+let
+  cfg = config.services.swaylock;
+in
+{
+  options.services.swaylock = {
+    enable = mkEnableOption "Enable swaylock";
+    package = mkOption {
+      type = types.package;
+      default = pkgs.swaylock;
+    };
+  };
+  config = mkIf cfg.enable {
+    security.pam.services.swaylock.text = readFile "${cfg.package}/etc/pam.d/swaylock";
+  };
+}