Finally, the guide on how to painlessly work with Sidekiq and ActiveJob I’ve been working on for so long is out. I’m extremely happy to share it with you. It’s based on Sidekiq’s wiki, ActiveJob documentation, numerous background jobs related code reviews, and known and rare pitfalls me and my colleagues experienced in our practice during past years. Hope you’ll find it useful. As for me, if the company I worked for had this guide before starting DelayedJob to Sidekiq migration, the migration would go way more smoothly and would save us from major headaches. Some of the information in this guide can’t be found in any other source. It’s a common belief that ActiveJob is redundant when working with Sidekiq, and bare Sidekiq is preferable. It’s hard to argue with that. Please don’t be repelled by the very first guidelines, glance over the rest of the guide. The guide covers both topics, even Sidekiq part prevails. Read between the lines and you’ll realize the unknown unknowns there actually are in background job processing. The guide is not nearly complete. There’s a ticket which I used as a todo list of guidelines that should be added to the guide. You can help here, too. Pull requests, additions to the todo list and any feedback are kindly appreciated.