diff --git a/webpack.mix.js b/webpack.mix.js
index 222f6a1..36efb78 100644
--- a/webpack.mix.js
+++ b/webpack.mix.js
@@ -4,8 +4,8 @@ const mix = require('laravel-mix')
 require('laravel-mix-polyfill')
 require('laravel-mix-clean')
 
-let assetDir = 'assets'
-let polyfill = {
+const assetDir = 'assets'
+const polyfill = {
     enabled: true,
     bugfixes: true,
     useBuiltIns: "usage",