I’m always saying that there’s a thin line between good and bad practice, and this thin line is named “Context”. That’s also true for the (anti-)pattern I’m calling “Requeuing Roulette”.What’s the Requeuing Roulette? As the name suggests, this technique involves putting a message back into the queue. It also (correctly) suggests that we’re hoping for the best. And sometimes we may be lucky to be true. Let's discuss pros and cons of it!

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Explores the "Requeuing Roulette" pattern in event-driven systems, where messages are put back into queues hoping for correct ordering. While this technique can work when messages aren't causally correlated and consumers are stable, it creates risks under load: messages may be reprocessed out of order, causing race conditions and CPU waste. The pattern attempts to maintain strict ordering while maximizing throughput, but this trade-off often fails in distributed systems. Better alternatives include using message grouping features (RabbitMQ routing keys, SQS message groups, Service Bus sessions) or streaming solutions like Kafka that handle ordering through partitions. Understanding actual ordering requirements and choosing simpler solutions typically beats trying to make requeueing work reliably.

Requeuing Roulette in Event-Driven Architecture and Messaging