diff --git a/bgpwtf/machines/modules/rename-interfaces.nix b/bgpwtf/machines/modules/rename-interfaces.nix
new file mode 100644
index 0000000..bbb5c81
--- /dev/null
+++ b/bgpwtf/machines/modules/rename-interfaces.nix
@@ -0,0 +1,29 @@
+# Sketchy little module to renamei interfaces by MAC.
+# This only works on startup.
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+  cfg = config.hscloud.renameInterfaces;
+in {
+  options.hscloud.renameInterfaces = mkOption {
+    type = with types; attrsOf (submodule {
+      options = {
+        mac = mkOption {
+          type = types.str;
+          description = ''
+            MAC address to match by, in hexadecimal form (ie. ac:1f:6b:1c:d7:ae).
+          '';
+        };
+      };
+    });
+    description = ''
+      Interfaces to rename by property (eg. MAC address).
+    '';
+  };
+
+  config.services.udev.extraRules = concatStringsSep "\n" (mapAttrsToList (n: v: ''
+    ACTION=="add", SUBSYSTEM=="net", ATTR{address}=="${v.mac}", ATTR{addr_assign_type}=="0", NAME="${n}"
+  '') cfg);
+}