diff --git a/lib/app/app.js b/lib/app/app.js
index c2fa6728ec..ad7fb7675d 100644
--- a/lib/app/app.js
+++ b/lib/app/app.js
@@ -6,6 +6,7 @@ import dataMixin from './dataMixin'
 import NotFound from '@notFound'
 import { routes } from '@temp/routes'
 import { siteData } from '@temp/siteData'
+import enhanceApp from '@temp/enhanceApp'
 
 // suggest dev server restart on base change
 if (module.hot) {
@@ -64,14 +65,20 @@ export function createApp () {
     }
   })
 
-  const app = new Vue({
-    router,
-    render (h) {
-      return h('div', { attrs: { id: 'app' }}, [
-        h('router-view', { ref: 'layout' })
-      ])
-    }
-  })
+  const options = {}
+
+  enhanceApp({ Vue, options, router })
+
+  const app = new Vue(
+    Object.assign(options, {
+      router,
+      render (h) {
+        return h('div', { attrs: { id: 'app' }}, [
+          h('router-view', { ref: 'layout' })
+        ])
+      }
+    })
+  )
 
   return { app, router }
 }
diff --git a/lib/prepare.js b/lib/prepare.js
index 00c65973fe..a62dc0732f 100644
--- a/lib/prepare.js
+++ b/lib/prepare.js
@@ -50,6 +50,16 @@ if (!Object.assign) Object.assign = require('object-assign')`
     await writeTemp(`override.styl`, hasUserOverride ? `@import(${JSON.stringify(overridePath)})` : ``)
   }
 
+  // 6. handle enhanceApp.js
+  const enhancePath = path.resolve(sourceDir, '.vuepress/enhanceApp.js')
+  const hasEnhancePath = fs.existsSync(enhancePath)
+  await writeTemp(
+    'enhanceApp.js',
+    hasEnhancePath
+      ? `export { default } from ${JSON.stringify(enhancePath)}`
+      : `export default function () {}`
+  )
+
   return options
 }