nixos/hosts/Tibo-NixDesk/default.nix

@@ -20,6 +20,7 @@
     networking = {
       networkmanager.enable = true;
       openconnect-sso.enable = true;
+      openvpn.enable = true;
     };
 
     nix = {

nixos/modules/networking/default.nix

@@ -2,5 +2,6 @@
   imports = [
     ./networkmanager
     ./openconnect-sso
+    ./openvpn
   ];
 }

nixos/modules/networking/openvpn/default.nix

@@ -0,0 +1,14 @@
+{ config, lib, ... }:
+
+let
+  cfg = config.sisyphus.networking.openvpn;
+in {
+  options.sisyphus.networking.openvpn.enable = lib.mkEnableOption "OpenVPN client";
+
+  config = lib.mkIf cfg.enable {
+    programs.openvpn3.enable = true;
+
+    # https://github.com/NixOS/nixpkgs/issues/379074
+    services.resolved.enable = true;
+  };
+}