SystemStackError (stack level too deep)

Ever had this in a controller?

Completed 500 Internal Server Error in 13606ms
SystemStackError (stack level too deep): activesupport (3.2.9) lib/active_support/callbacks.rb:409

And the same active record queries in the development or production log over and over again?

Chances are that you have misspelled something in the controller action and that the controller is calling itself over and over again until it crashes.

Have a controller action that is called article and a variable that is declared articles but then used as article could cause this.