diff --git a/config.ru b/config.ru
index e90863a5c2..a2525c8136 100644
--- a/config.ru
+++ b/config.ru
@@ -2,11 +2,14 @@
 
 if defined?(Unicorn)
   require 'unicorn'
-  # Unicorn self-process killer
-  require 'unicorn/worker_killer'
 
-  # Max memory size (RSS) per worker
-  use Unicorn::WorkerKiller::Oom, (200 * (1 << 20)), (250 * (1 << 20))
+  if ENV['RAILS_ENV'] == 'production' || ENV['RAILS_ENV'] == 'staging'
+    # Unicorn self-process killer
+    require 'unicorn/worker_killer'
+
+    # Max memory size (RSS) per worker
+    use Unicorn::WorkerKiller::Oom, (200 * (1 << 20)), (250 * (1 << 20))
+  end
 end
 
 require ::File.expand_path('../config/environment',  __FILE__)