ruby - config.ru if statement for production -

In my config.ru, I would like to set up a code block that will run specific code based on environment.

I tried some code but I have not got any success any suggestions?

  if ENV ['RQNV'] To_s.eql? ('Development') bundler. Request (default: development) end    
 
 
 I believe that you  Want to see  ENV ['RACK_ENV']  instead of ENV [x] ['RAKE_ENV'] .