diff --git a/readme.md b/readme.md
index b55f24ed..4d81007d 100644
--- a/readme.md
+++ b/readme.md
@@ -1012,7 +1012,7 @@ module.exports = {
 Or use a function:
 
 ```js
-module.exports = (phase, {defaultConfig}){
+module.exports = (phase, {defaultConfig}) => {
   //
   // https://github.com/zeit/
   return {