diff --git a/turbopack/crates/turbopack-node/js/src/transforms/postcss.ts b/turbopack/crates/turbopack-node/js/src/transforms/postcss.ts
index ebacd2404bfce8..9579bb7b6dc82d 100644
--- a/turbopack/crates/turbopack-node/js/src/transforms/postcss.ts
+++ b/turbopack/crates/turbopack-node/js/src/transforms/postcss.ts
@@ -5,6 +5,7 @@ declare const __turbopack_external_require__: (
 ) => any
 
 import type { Processor } from 'postcss'
+import { workerData } from 'worker_threads'
 
 // @ts-ignore
 import postcss from '@vercel/turbopack/postcss'
@@ -133,8 +134,7 @@ export default async function transform(
   }
 }
 
-// @ts-ignore
-if (typeof self !== 'undefined' && self.workerData && self.workerData.binding) {
+if (workerData && workerData.binding) {
   // @ts-ignore
   const { run } = require('../web_worker/evaluate')
   run(async () => {
diff --git a/turbopack/crates/turbopack-node/js/src/transforms/webpack-loaders.ts b/turbopack/crates/turbopack-node/js/src/transforms/webpack-loaders.ts
index e746a880d03731..8814968bca4ecd 100644
--- a/turbopack/crates/turbopack-node/js/src/transforms/webpack-loaders.ts
+++ b/turbopack/crates/turbopack-node/js/src/transforms/webpack-loaders.ts
@@ -17,6 +17,7 @@ import {
 } from './transforms'
 import fs from 'fs'
 import path from 'path'
+import { workerData } from 'worker_threads'
 
 export type IpcInfoMessage =
   | {
@@ -509,8 +510,7 @@ const transform = (
 
 export { transform as default }
 
-// @ts-ignore
-if (typeof self !== 'undefined' && self.workerData && self.workerData.binding) {
+if (workerData && workerData.binding) {
   // @ts-ignore
   const { run } = require('../web_worker/evaluate')
   run(async () => {
diff --git a/turbopack/crates/turbopack-node/js/src/web_worker/evaluate.ts b/turbopack/crates/turbopack-node/js/src/web_worker/evaluate.ts
index f184050a8936df..87a1dfbd884f9d 100644
--- a/turbopack/crates/turbopack-node/js/src/web_worker/evaluate.ts
+++ b/turbopack/crates/turbopack-node/js/src/web_worker/evaluate.ts
@@ -6,20 +6,13 @@ import {
 } from '../worker_thread/taskChannel'
 import { structuredError } from '../error'
 import type { Channel } from '../types'
+import { workerData, threadId as workerId } from 'worker_threads'
 
-export type Self = DedicatedWorkerGlobalScope & {
-  workerData: {
-    workerId: number
-    cwd: string
-    binding: Binding
-  }
-}
+export type Self = DedicatedWorkerGlobalScope
 
 export declare const self: Self
-// @ts-ignore
-const { workerId } = self.workerData
 
-let binding: Binding = self.workerData.binding
+let binding: Binding = workerData.binding
 
 binding.workerCreated(workerId)