diff --git a/config/constants/settings/definition.rb b/config/constants/settings/definition.rb
index a5e4a46e539..715707dd6b7 100644
--- a/config/constants/settings/definition.rb
+++ b/config/constants/settings/definition.rb
@@ -537,7 +537,7 @@ module Settings
       },
       host_name: {
         format: :string,
-        default: "#{ENV.fetch('HOST', 'localhost')}:#{ENV.fetch('PORT', 3000)}",
+        default: -> { "#{ENV.fetch('HOST', 'localhost')}:#{ENV.fetch('PORT', 3000)}" },
         default_by_env: {
           # We do not want to set a localhost host name in production
           production: nil