diff --git a/config/environments/production.rb b/config/environments/production.rb
index 3bbd6ac..64fd610 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -81,8 +81,8 @@
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
 
-   # Compress JavaScripts and CSS.
-  config.assets.js_compressor = :uglifier
+  # Compress JavaScripts and CSS.
+  config.assets.js_compressor = Uglifier.new(harmony: true)
   # config.assets.css_compressor = :sass
 
   # Do not fallback to assets pipeline if a precompiled asset is missed.