diff --git a/express-zod-api/src/mapping-helpers.ts b/express-zod-api/src/mapping-helpers.ts
deleted file mode 100644
index ea193eba6d..0000000000
--- a/express-zod-api/src/mapping-helpers.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-/**
- * @fileoverview Mapping utils for Zod Runtime Plugin (remap)
- * @link https://stackoverflow.com/questions/55454125/typescript-remapping-object-properties-in-typesafe
- */
-type TuplesFromObject<T> = {
-  [P in keyof T]: [P, T[P]];
-}[keyof T];
-
-type GetKeyByValue<T, V> =
-  TuplesFromObject<T> extends infer TT
-    ? TT extends [infer P, V]
-      ? P
-      : never
-    : never;
-
-export type Remap<T, U extends { [P in keyof T]?: V }, V extends string> = {
-  [P in NonNullable<U[keyof U]>]: T[GetKeyByValue<U, P>];
-};
-
-export type Intact<T, U> = { [K in Exclude<keyof T, keyof U>]: T[K] };
diff --git a/express-zod-api/src/zod-plugin.ts b/express-zod-api/src/zod-plugin.ts
index 9ffbea63f3..737130d5a8 100644
--- a/express-zod-api/src/zod-plugin.ts
+++ b/express-zod-api/src/zod-plugin.ts
@@ -10,7 +10,6 @@
 import * as R from "ramda";
 import { z } from "zod/v4";
 import { getExamples, metaSymbol } from "./metadata";
-import { Intact, Remap } from "./mapping-helpers";
 import type {
   $ZodType,
   $ZodShape,
@@ -39,6 +38,8 @@ declare module "zod/v4/core" {
   }
 }
 
+export type Intact<T, U> = { [K in Exclude<keyof T, keyof U>]: T[K] };
+
 declare module "zod/v4" {
   interface ZodType<
     out Output = unknown,
@@ -68,7 +69,7 @@ declare module "zod/v4" {
       mapping: U,
     ): z.ZodPipe<
       z.ZodPipe<this, z.ZodTransform>, // internal type simplified
-      z.ZodObject<Remap<Shape, U, V> & Intact<Shape, U>, Config>
+      z.ZodObject<R.Remap<Shape, U> & Intact<Shape, U>, Config>
     >;
     remap<U extends $ZodShape>(
       mapper: (subject: Shape) => U,