Event routers are crucial components in event-driven architecture, connecting event consumers to producers, and their selection depends on specific use cases and project needs. The text contrasts traditional message brokers like RabbitMQ with modern event streaming platforms such as Apache Kafka. RabbitMQ is noted for its ease of use, persistent message handling, and well-established community, but it faces challenges such as horizontal scaling issues and tight consumer coupling. In contrast, Kafka offers flexibility, scalability, and resilience through its ability to retain and replay event logs, though it comes with a complexity and learning curve. The choice between these event routers hinges on factors such as throughput requirements and scalability needs, with RabbitMQ suited for lower throughput scenarios and Kafka for higher demands. Additionally, integrating event-driven architecture with serverless platforms, such as Koyeb, can enhance scalability and reduce operational costs, offering advantages like autoscaling and freeing IT teams to focus on business-specific tasks.