diff --git a/config/initializers/rails_erd.rb b/config/initializers/rails_erd.rb
new file mode 100644
index 0000000..32e6153
--- /dev/null
+++ b/config/initializers/rails_erd.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+if Rails.env.development?
+  require 'rails_erd/domain'
+
+  module RailsERD
+    class Domain
+      def name
+        return unless defined?(Rails) && Rails.application
+
+        if Rails.application.class.respond_to?(:module_parent)
+          Rails.application.class.module_parent.name
+        else
+          Rails.application.class.parent.name
+        end
+      end
+    end
+  end
+end