If you want to know how to sustainably manage background jobs in your Rails app, you should be using Sidekiq, and you should by my book, Ruby on Rails Background Jobs with Sidekiq. $9.99, ebook only, a scant 70 pages.
Since 2011, I’ve been responsible for apps that had a lot of background jobs, and I’ve been on-call for those apps. Believe me when I tell you, you don’t want to learn how to write idempotent jobs, create self-healing retriable processes, or manage queues that way. It takes too long and its too stressful. Just read the book I wish I had back then.