What is the role of Sidekiq in distributed Rails architecture?

Sidekiq handles background processing using Redis-based job queues for scalability and reliability.

Sidekiq processes jobs asynchronously outside request-response cycle. It uses Redis for queue storage and multi-threaded workers for concurrency. It supports retries, dead job tracking, and middleware instrumentation. In distributed systems, it offloads heavy tasks like email delivery, payment processing, and data aggregation.