diff --git a/_build_common.sh b/_build_common.sh
index 833611b..0838336 100755
--- a/_build_common.sh
+++ b/_build_common.sh
@@ -1,3 +1,7 @@
 #!/bin/bash
 
 export FRONT_END_HASH=$(git rev-parse --short HEAD)
+
+if [ -z "$ESP_LANG" ]; then
+	export ESP_LANG=en
+fi
diff --git a/_build_css.sh b/_build_css.sh
index 8679569..3bd074e 100755
--- a/_build_css.sh
+++ b/_build_css.sh
@@ -10,4 +10,4 @@ else
 fi
 
 mkdir -p out/css
-npm run sass -- --output-style ${stylearg} sass/app.scss "out/css/app.$FRONT_END_HASH.css"
+npm run sass -- --output-style ${stylearg} sass/app.scss "out/css/app.$FRONT_END_HASH-$ESP_LANG.css"
diff --git a/pages/_head.php b/pages/_head.php
index af974b9..8ca2eb1 100644
--- a/pages/_head.php
+++ b/pages/_head.php
@@ -5,8 +5,8 @@
 	<meta http-equiv="X-UA-Compatible" content="IE=edge">
 	<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no, maximum-scale=1">
 	<title><?= $_GET['PAGE_TITLE'] ?></title>
-	<link href="/css/app.<?= GIT_HASH ?>.css" rel="stylesheet">
-	<script src="/js/app.<?= GIT_HASH ?>.js"></script>
+	<link href="/css/app.<?= GIT_HASH . '-' . LOCALE ?>.css" rel="stylesheet">
+	<script src="/js/app.<?= GIT_HASH . '-' . LOCALE ?>.js"></script>
 	<script>
 		var _root = <?= JS_WEB_ROOT ?>;
 		var _demo = <?= (int)ESP_DEMO ?>;
diff --git a/webpack.config.js b/webpack.config.js
index 3b79b40..e332745 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -3,6 +3,7 @@ const { execSync } = require('child_process')
 const path = require('path')
 
 let hash = execSync('git rev-parse --short HEAD').toString().trim()
+let lang = process.env.ESP_LANG || 'en'
 
 let plugins = []
 let devtool = 'source-map'
@@ -23,7 +24,7 @@ module.exports = {
   entry: './js',
   output: {
     path: path.resolve(__dirname, 'out', 'js'),
-    filename: `app.${hash}.js`
+    filename: `app.${hash}-${lang}.js`
   },
   module: {
     rules: [