To use Unicorn instead of thin on heroku, do the following: Add gem "unicorn" to your Gemfile Add a Procfile Add config/unicorn.rb Procfile 1 web: bundle exec unicorn -p $PORT -c ./config/unicorn.rb 2 worker: bundle exec rake jobs:work 1 preload_app true 2 worker_processes 4 # amount of unicorn workers to spin up 3 timeout 30 # restarts workers that hang for 30 seconds 4 after_fork do |server, wor