Heroku Cedar: how to stop using WEBrick

In my Gemfile I have:

gem 'thin'

But when I push my application to Her开发者_运维百科oku Cedar, WEBrick is still used ("Booting WEBrick" in logs).

Where might be a problem?

You just need to create a Procfile and add the following line:

web: bundle exec rails server -p $PORT thin -e $RACK_ENV

Push that to Heroku and you'll be all set.