This Atlassian blog post details Trello's migration from RabbitMQ to Kafka for its websocket architecture. RabbitMQ's unreliability during network partitions and high costs associated with queue creation and deletion prompted the switch. The article compares various queuing systems, highlighting Kafka's superior failover capabilities and in-order message delivery. Trello implemented a master-client architecture with Kafka, resulting in improved performance, reduced costs, and fewer outages. Key performance improvements included a 33% decrease in memory usage and a substantial cost reduction.