This architecture demonstrates an event-driven serverless approach using microservices, where small, independent services communicate through well-defined APIs. The system leverages API Gateway for both HTTP and WebSocket communication, allowing real-time interaction with the user. EventBridge acts as the central event bus, enabling decoupled communication between Lambda functions, which process requests, perform business logic, and interact with DynamoDB for data storage and retrieval. The architecture combines the benefits of microservices, event-driven design, and serverless computing, resulting in a scalable, flexible, and maintainable solution.

The decision to adopt a serverless architecture for this order processing system is driven by the need for efficient handling of real-time communication and high-volume transactions. Serverless design principles enable the system to scale automatically based on demand, ensuring optimal performance and cost-efficiency without the need for manual infrastructure management. This event-driven processing model allows the system to react quickly to incoming requests, while the use of managed services reduces operational overhead.