diff --git a/config/application.rb b/config/application.rb
index f4a8e7354..a0c5f5a7a 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -39,6 +39,6 @@ class Application < Rails::Application
     #
     # config.eager_load_paths << Rails.root.join("extras")
 
-    Dir[Rails.root.join('lib/core_ext/**/*.rb')].each { |file| require file }
+    Dir[Rails.root.join("lib/core_ext/**/*.rb")].each { |file| require file }
   end
 end
diff --git a/lib/core_ext/enumerable.rb b/lib/core_ext/enumerable.rb
index f48aa6576..5d77a272e 100644
--- a/lib/core_ext/enumerable.rb
+++ b/lib/core_ext/enumerable.rb
@@ -37,6 +37,9 @@ def group_by_equality(&block)
   end
 end
 
-module Enumerable
-  include CoreExt::Enumerable
+Enumerable.include(CoreExt::Enumerable)
+
+# Re-include Enumerable in classes that include it to ensure core extension methods are included
+[Array, Hash, Range, Set].each do |klass|
+  klass.include Enumerable
 end