diff --git a/src/util/extend.ts b/src/util/extend.ts
index 6383bde..1618656 100644
--- a/src/util/extend.ts
+++ b/src/util/extend.ts
@@ -20,6 +20,7 @@ import { CommonKeys } from "."
 // ]>
 
 
+// TODO: use OverrideProperties from type-fest?
 export type Extend<T extends readonly object[]> = (
     T extends [
         infer Super,