diff --git a/build/lib/bundle.js b/build/lib/bundle.js
index 7d0c8d9b55e..143e64e087d 100644
--- a/build/lib/bundle.js
+++ b/build/lib/bundle.js
@@ -14,6 +14,9 @@ const vm = require("vm");
 function bundle(entryPoints, config, callback) {
     const entryPointsMap = {};
     entryPoints.forEach((module) => {
+        if (entryPointsMap[module.name]) {
+            throw new Error(`Cannot have two entry points with the same name '${module.name}'`);
+        }
         entryPointsMap[module.name] = module;
     });
     const allMentionedModulesMap = {};
diff --git a/build/lib/bundle.ts b/build/lib/bundle.ts
index 562b050d1fd..ce1f6e61662 100644
--- a/build/lib/bundle.ts
+++ b/build/lib/bundle.ts
@@ -100,6 +100,9 @@ export interface ILoaderConfig {
 export function bundle(entryPoints: IEntryPoint[], config: ILoaderConfig, callback: (err: any, result: IBundleResult | null) => void): void {
 	const entryPointsMap: IEntryPointMap = {};
 	entryPoints.forEach((module: IEntryPoint) => {
+		if (entryPointsMap[module.name]) {
+			throw new Error(`Cannot have two entry points with the same name '${module.name}'`);
+		}
 		entryPointsMap[module.name] = module;
 	});
 
diff --git a/src/buildfile.js b/src/buildfile.js
index 7588e1f8b3c..5b9b061df45 100644
--- a/src/buildfile.js
+++ b/src/buildfile.js
@@ -7,8 +7,8 @@ const { createModuleDescription, createEditorWorkerModuleDescription } = require
 
 exports.base = [
 	{
-		name: 'vs/base/common/worker/simpleWorker',
-		include: ['vs/editor/common/services/editorSimpleWorker'],
+		name: 'vs/editor/common/services/editorSimpleWorker',
+		include: ['vs/base/common/worker/simpleWorker'],
 		prepend: ['vs/loader.js', 'vs/nls.js'],
 		append: ['vs/base/worker/workerMain'],
 		dest: 'vs/base/worker/workerMain.js'