Redis Lists Explained: How to Build Simple Queues and Capped Feeds

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Redis lists are ordered string sequences that support push and pop operations from either end, making them well-suited for basic job queues and recent-item feeds. Producers can add jobs using LPUSH while workers retrieve them via RPOP or the blocking BRPOP, which eliminates inefficient polling by making workers wait until a job is available. A key limitation is that plain list-based queues offer at-most-once delivery, meaning a job is lost if a worker crashes after popping it but before completing the task. The LMOVE command partially addresses this by atomically moving a job to a separate processing list, enabling crash recovery through manual bookkeeping. For use cases requiring strict delivery guarantees and acknowledgements, Redis Streams are the recommended alternative, while lists remain a practical choice for best-effort queues and bounded recent-activity feeds.

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