config/environments/custom/production.rb
Rails.application.configure do
# Overwrite settings for the production environment or add your own
# custom settings for this environment. Note these changes will
# also affect the staging and preproduction environments, so edit the
# `config/environments/custom/staging.rb` and/or
# `config/environments/custom/preproduction.rb` files if you don't
# want these changes to be applied there as well.
end