Are worker gems like Sidekiq still needed for a basic Rails application

Starting from Rails 7.1, Puma will automatically spawn x worker threads where x is the amount of available processors.


This brings up the question on how to handle workers in a simple dockerized Rails production app.


In the case of a simple Rails application that occasionally sends some mails asynchronously and periodically cleans up a few ActiveRecord Blobs, are worker Gems like Sidekiq still needed? Or is the default configuration of Puma enough to get the job done?