diff --git a/source/layouts/layout.html.haml b/source/layouts/layout.html.haml
index f57b928..90c3fc9 100644
--- a/source/layouts/layout.html.haml
+++ b/source/layouts/layout.html.haml
@@ -36,7 +36,7 @@
       = stylesheet_link_tag 'application'
     - else
       = stylesheet_link_tag 'legacy'
-    = javascript_include_tag 'all'
+    = javascript_include_tag 'all', defer: true
 
   %body
     %article