MESSAGE QUEUES & EVENT-DRIVEN SYSTEMS

How do applications communicate, process tasks in the background, and respond to thousands of events without making users wait?

Message Queues & Event-Driven Systems explores the technology and design principles behind these workflows. Through clear explanations, colorful diagrams, and practical examples, it helps you understand how messages move between services—and how to make that communication reliable.

Begin with producers, consumers, queues, topics, and publish-subscribe patterns. Explore RabbitMQ, Apache Kafka, and Amazon SQS/SNS, understand their differences, and learn how to choose an approach for background jobs, notifications, business workflows, and event streaming.

Go beyond sending messages to understand what happens when things go wrong. Discover how acknowledgments, retries, dead-letter queues, and idempotent processing help applications handle failures and duplicate messages. Then explore Event Sourcing and CQRS, learning how event histories and separate read and write models can support more complex systems—and when their added complexity is justified.

A practical order-to-payment example connects the concepts, showing how payment processing, inventory updates, and notifications work together through events.

Designed for students, developers, and technology professionals, this book builds a clear foundation for designing applications that communicate effectively, recover from failures, and grow with demand. Basic familiarity with software applications is helpful; prior messaging experience is not required.