cqrs-implementation

You need CQRS when your system requires independent read and write paths, event-driven updates, and optimized reporting or API access. This Skill designs command-query splits for scalable applications needing independent scaling for writes and queries.

To design a command bus and query bus for a FastAPI service, this Skill defines distinct handler flows for state changes and data retrieval, applying command-query separation to reduce coupling and optimize independent read and write paths.

The best way to build event-driven read models is by creating projections and denormalized views that stay in sync with application events, allowing your read path to be optimized independently from your write operations.

Handle eventual consistency and read-your-writes scenarios in CQRS by applying consistency and recovery patterns, including projection rebuilding, to ensure production systems stay in sync during event-driven state updates.

CQRS works well for reporting-heavy applications and trading platforms because it separates write operations from read operations, allowing complex reporting queries to scale independently without impacting transactional write performance.