In Rails 4.2,
Active Job was integrated with Action Mailer
to send emails asynchronously.
Rails provides deliver_later method to enqueue mailer jobs.
Note that the task of delivering email was put in queue called
In Rails 4.x, all background jobs are given queue named “default” except
for mailers. All outgoing mails are given the queue named “mailers” and
we do not have the option of changing this queue name from “mailers” to
Since Rails 4.x comes with minimum of two queues it makes difficult to
use queuing services like que which
relies on applications having only one queue.
Customizing queue name in Rails 5
In Rails 5, we can now
change queue name
for mailer jobs
using following configuration.