Great question!
Sidequest uses transaction-level row locks (`SELECT ... FOR UPDATE SKIP LOCKED`) when fetching jobs. This means each worker thread only locks the specific job rows it’s about to process, minimizing lock contention and avoiding blocking other queries. This pattern is inspired by Oban’s advisory-lock approach, but instead of using explicit advisory locks, Sidequest relies on the database’s built-in row locking mechanism.
The only drawback is that Sidequest will require one or two connections to your DB. If you enqueue jobs from within other jobs, then each job that requests an enqueue will also connect to your DB (lazily connected upon request - if your job does not enqueue, no connection is created). However, you can configure the number of concurrent workers per queue and globally, so you control how much load Sidequest puts on your database.
I hope that answers your question :)