diff --git a/lib/cypress_on_rails/server.rb b/lib/cypress_on_rails/server.rb
index 15390f0..fdeb1e2 100644
--- a/lib/cypress_on_rails/server.rb
+++ b/lib/cypress_on_rails/server.rb
@@ -69,7 +69,7 @@ def start_server(&block)
       run_hook(config.before_server_start)
       
       ENV['CYPRESS'] = '1'
-      ENV['RAILS_ENV'] = 'test'
+      ENV['RAILS_ENV'] ||= 'test'
       
       server_pid = spawn_server