diff --git a/bgpwtf/machines/modules/gretap.nix b/bgpwtf/machines/modules/gretap.nix
new file mode 100644
index 0000000..f4e1a7b
--- /dev/null
+++ b/bgpwtf/machines/modules/gretap.nix
@@ -0,0 +1,62 @@
+# Support for GRETap interfaces in NixOS' scripted networking.
+#
+# We currently only use it in the edge01.waw test framework to bring vlans
+# across test VMs.
+
+{ config, pkgs, lib, ... }:
+
+with lib;
+
+let
+  cfg = config.hscloud.gretap;
+
+in {
+  options.hscloud.gretap = {
+    interfaces = mkOption {
+      type = with types; attrsOf (submodule {
+        options = {
+          localV4 = mkOption {
+            type = types.str;
+            description = "Local outer IPv4 address";
+          };
+          remoteV4 = mkOption {
+            type = types.str;
+            description = "Remote outer IPv4 address";
+          };
+          id = mkOption {
+            type = types.int;
+            description = "Tunnel ID";
+          };
+          parent = mkOption {
+            type = types.str;
+            description = "Parent/outer device";
+          };
+        };
+      });
+      description = ''
+        GRETap interfaces to create.
+      '';
+    };
+  };
+
+  config.boot.kernelModules = [ "fou" ];
+  config.systemd.services = mapAttrs' (name: value: nameValuePair "${name}-gretap" {
+    wants = [
+      "${name}-netdev.service"
+      "network-addresses-${value.parent}.service"
+    ];
+    after = [
+      "network-addresses-${value.parent}.service"
+    ];
+    before = [
+      "network-addresses-${name}.service"
+    ];
+    wantedBy = [
+      "network-addresses-${name}.service"
+    ];
+    serviceConfig = {
+      Type = "oneshot";
+      ExecStart = "${pkgs.iproute}/bin/ip link add name ${name} type gretap remote ${value.remoteV4} local ${value.localV4} key ${toString value.id}";
+    };
+  }) cfg.interfaces;
+}