diff --git a/types/defines/rpc.d.ts b/types/defines/rpc.d.ts
index 63daab42f9a..e2c5221056c 100644
--- a/types/defines/rpc.d.ts
+++ b/types/defines/rpc.d.ts
@@ -46,7 +46,7 @@ declare namespace Rpc {
     | Set<T extends Set<infer U> ? Serializable<U> : never>
     | ReadonlyArray<T extends ReadonlyArray<infer U> ? Serializable<U> : never>
     | {
-        [K in keyof T]: K extends number | string ? Serializable<T[K]> : never;
+        [K in keyof T as K extends string | number ? K : never]: Serializable<T[K]>;
       }
     // Special types
     | Stub<Stubable>