diff --git a/lib/delayed/worker.rb b/lib/delayed/worker.rb
index 1a352f775..b4497649b 100644
--- a/lib/delayed/worker.rb
+++ b/lib/delayed/worker.rb
@@ -116,7 +116,7 @@ def self.setup_lifecycle
     end
 
     def self.reload_app?
-      defined?(ActionDispatch::Reloader) && Rails.application.config.cache_classes == false
+      defined?(ActionDispatch::Reloader) && defined?(Rails) && Rails.application.config.cache_classes == false
     end
 
     def self.delay_job?(job)
@@ -326,7 +326,7 @@ def reserve_job
 
     def reload!
       return unless self.class.reload_app?
-      if defined?(ActiveSupport::Reloader)
+      if defined?(ActiveSupport::Reloader) && defined?(Rails)
         Rails.application.reloader.reload!
       else
         ActionDispatch::Reloader.cleanup!