event-sourcing-architect

Event sourcing records every state change as an immutable fact in an event store, enabling full audit trails and temporal data queries. This approach provides a robust foundation for systems requiring complex workflow orchestration and eventual consistency.

CQRS separates command and query responsibilities into distinct models to optimize read and write performance. Projection building creates specialized read models from the event store, allowing queries to execute efficiently without impacting write operations.

Saga orchestration manages complex distributed business workflows by defining compensating actions for each step. Instead of distributed transactions, sagas coordinate events across services to ensure eventual consistency and rollback failed processes.

You need event-driven architecture when designing systems requiring complete audit trails, complex workflow orchestration, or temporal data queries. It is essential for robust, scalable systems where tracking every state change as an event is critical.

Design an event store by recording immutable events for every order state change, such as payment and shipping processes. This enables full audit trails, temporal queries, and eventual consistency across the e-commerce system workflow.

Eventual consistency means read models may lag behind the event store until projections catch up. This requires handling stale data and implementing compensation logic in saga orchestration to manage complex distributed workflows reliably.