generify the vpn setup

modules/nixos/default.nix

@@ -1,6 +1,5 @@
 # Add your reusable NixOS modules to this directory, on their own file (https://nixos.wiki/wiki/Module).
 # These should be stuff you would like to share with others, not your personal configurations.
 {
-  # List your module files here
-  contabo.wan = import ./contabo/wan;
+  vpn-ip = import ./vpn-ip;
 }

modules/nixos/vpn-ip/default.nix

@@ -0,0 +1,14 @@
+{lib, ...}:
+with lib; {
+  # Declare what settings a user of this "hello.nix" module CAN SET.
+  options.services.vpn-ip = {
+    ip = mkOption {
+      type = types.str;
+      default = "0";
+    };
+    publicKey = mkOption {
+      type = types.str;
+      default = "";
+    };
+  };
+}