Nginx Phusion Passenger Ruby: Don't send app log to nginx log
Solution 1:
There is a way to do it with the passenger_app_log_file directive, but the bad news is that it is a paid Passenger Enterprise option. See here: https://www.phusionpassenger.com/library/config/nginx/reference/#passenger_app_log_file
I'm slightly amused that Passenger takes over stdout then charges you to get it back.