How does Rails handle large-scale event-driven architectures using message brokers?

Rails uses message brokers like Kafka or RabbitMQ to implement event-driven architectures where services communicate asynchronously through events.

In large-scale systems, Rails often emits domain events instead of directly calling other services. These events are published to message brokers such as Kafka or RabbitMQ. Consumers subscribe and react independently. This decouples services, improves scalability, and enables eventual consistency. Rails typically integrates via background jobs or dedicated event producer libraries. Key concerns include idempotency, ordering, replayability, and schema evolution of events.