Heroku running rails 2.x Puma error

Question

I'm getting the error below in my heroku logs. The Puma line and config file are the defaults as supplied by Heroku.

Starting process with command bundle exec puma -C config/puma.rb invalid option: -C

Has anyone seen this before?

Answer 1

Turns out it was a puma version issue. I was running an older version that does not support the -C option.