diff --git a/gulpfile.js b/gulpfile.js
index fc75fc35..84412653 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -34,7 +34,6 @@ var bannerPlugin = new webpack.BannerPlugin(createBanner(), {
   raw: true
 });
 
-// TODO: the moment.js language files should be excluded by default (they are quite big)
 var webpackConfig = {
   entry: ENTRY,
   output: {
@@ -44,8 +43,12 @@ var webpackConfig = {
     filename: VIS_JS,
     sourcePrefix: '  '
   },
-  // exclude requires of moment.js language files
   module: {
+    loaders: [
+      { test: /\.js$/, exclude: /node_modules/, loader: '6to5-loader'}
+    ],
+
+    // exclude requires of moment.js language files
     wrappedContextRegExp: /$^/
   },
   plugins: [ bannerPlugin ],
diff --git a/lib/timeline/Core.js b/lib/timeline/Core.js
index 72427352..140bc10a 100644
--- a/lib/timeline/Core.js
+++ b/lib/timeline/Core.js
@@ -214,9 +214,7 @@ Core.prototype.setOptions = function (options) {
   }
 
   // propagate options to all components
-  this.components.forEach(function (component) {
-    component.setOptions(options);
-  });
+  this.components.forEach(component => component.setOptions(options));
 
   // TODO: remove deprecation error one day (deprecated since version 0.8.0)
   if (options && options.order) {
@@ -270,9 +268,7 @@ Core.prototype.destroy = function () {
   this.hammer = null;
 
   // give all components the opportunity to cleanup
-  this.components.forEach(function (component) {
-    component.destroy();
-  });
+  this.components.forEach(component => component.destroy());
 
   this.body = null;
 };
@@ -336,9 +332,7 @@ Core.prototype.clear = function(what) {
 
   // clear options of timeline and of each of the components
   if (!what || what.options) {
-    this.components.forEach(function (component) {
-      component.setOptions(component.defaultOptions);
-    });
+    this.components.forEach(component => component.setOptions(component.defaultOptions));
 
     this.setOptions(this.defaultOptions); // this will also do a redraw
   }
diff --git a/package.json b/package.json
index cd6db5c5..c97efb0b 100644
--- a/package.json
+++ b/package.json
@@ -34,6 +34,8 @@
     "keycharm": "^0.2.0"
   },
   "devDependencies": {
+    "6to5": "^2.12.2",
+    "6to5-loader": "^2.0.0",
     "clean-css": "latest",
     "gulp": "^3.8.5",
     "gulp-concat": "^2.2.0",