diff --git a/config/routes.rb b/config/routes.rb
index a901509e..57863a06 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -1,4 +1,5 @@
 Osem::Application.routes.draw do
+  mount LetterOpenerWeb::Engine, at: '/letter_opener' if Rails.env.development?
 
   mount LetterOpenerWeb::Engine, at: '/letter_opener' if Rails.env.development?