How to Build a Scalable Order Management System Using CQRS and Axon Framework

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A technical guide published on DEV Community outlines how to build a scalable Order Management System (OMS) using CQRS, Event Sourcing, and the Axon Framework with Spring Boot 3.x and Java 17. The architecture separates state-changing commands from read queries, enabling optimized performance since order status checks far outnumber actual order placements. Event Sourcing ensures an immutable audit trail by storing every state change as an ordered sequence of events rather than overwriting database records. The Order aggregate enforces business rules — such as preventing shipment before payment confirmation — by replaying stored events to reconstruct its current state. The guide walks developers through defining commands, events, and aggregates using immutable Java Records, with Axon Server serving as the event store and routing engine.

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