CQRS in Practice: Separating Reads and Writes Without the Hype

Most applications fail at scale not because they cannot write, but because their read models collide with write consistency requirements. What We're Building We are designing a user management service for a high-traffic SaaS platform. The system faces a classic bottleneck: administrative updates occur frequently, while public dashboards query user profiles millions of times per day. The goal is to prevent write operations from blocking read operations, which would degrade user experience. This article demonstrates a production-grade implementation of CQRS in Go to decouple these traffic patterns effectively. Step 1 — Define Interfaces Separately Establish a clear contract between the command layer and the query layer. This prevents accidental coupling between read and write logic at the design phase. By defining separate interfaces, the compiler guarantees that read code never executes write logic. type UserCommand interface { Execute(ctx context.Context) error } type UserQuery interfa