diff --git a/packages/unocss/build.config.ts b/packages/unocss/build.config.ts
index 5ee8d023f4..d77a4764a4 100644
--- a/packages/unocss/build.config.ts
+++ b/packages/unocss/build.config.ts
@@ -18,6 +18,8 @@ export default defineBuildConfig({
   declaration: true,
   externals: [
     'vite',
+    'webpack',
+    '@unocss/webpack',
   ],
   rollup: {
     emitCJS: true,
diff --git a/packages/unocss/src/webpack.ts b/packages/unocss/src/webpack.ts
index 9ca288031e..fd8cd19c05 100644
--- a/packages/unocss/src/webpack.ts
+++ b/packages/unocss/src/webpack.ts
@@ -14,5 +14,5 @@ export default function UnocssWebpackPlugin<Theme extends {}>(
         presetUno(),
       ],
     },
-  )
+  ) as any
 }