All this could have been avoided by using: if(getenv('tumblr_env') == 'production') { //See: http://php.net/manual/en/function.register-shutdown-function

All this could have been avoided by using: if(getenv('tumblr_env') == 'production') { //See: http://php.net/manual/en/function.register-shutdown-function.php register_shutdown_function('five_hundred_err_func') }