diff --git a/rendering/webpack.config.js b/rendering/webpack.config.js
index 948ce5c151..64fbb63861 100644
--- a/rendering/webpack.config.js
+++ b/rendering/webpack.config.js
@@ -22,5 +22,16 @@ module.exports = {
   context: __dirname,
   target: 'web',
   entry: entry,
-  devtool: 'source-map'
+  devtool: 'source-map',
+  module: {
+    rules: [{
+      test: /\.js$/,
+      use: {
+        loader: path.join(__dirname, '../examples/webpack/worker-loader.js')
+      },
+      include: [
+        path.join(__dirname, '../src/ol/worker')
+      ]
+    }]
+  }
 };
diff --git a/tasks/serialize-workers.js b/tasks/serialize-workers.js
index 0e2b14182f..cbf8929f34 100644
--- a/tasks/serialize-workers.js
+++ b/tasks/serialize-workers.js
@@ -20,6 +20,7 @@ async function build(input, {minify = true} = {}) {
     common(),
     resolve(),
     babel({
+      'externalHelpers': true,
       'presets': [
         [
           '@babel/preset-env',