diff --git a/integration/src/systemjs-angular-loader.js b/integration/src/systemjs-angular-loader.js
index 38e5cc5..4632964 100644
--- a/integration/src/systemjs-angular-loader.js
+++ b/integration/src/systemjs-angular-loader.js
@@ -23,7 +23,7 @@ module.exports.translate = function (load) {
 
   load.source = load.source
     .replace(templateUrlRegex, function (match, quote, url) {
-      let resolvedUrl = url;
+      var resolvedUrl = url;
 
       if (url.startsWith('.')) {
         resolvedUrl = basePath + url.substr(1);