Event Sourcing & CQRS Core Concepts Event Sourcing (TypeScript) Event Store Event-Sourced Aggregate CQRS Command Side Query Side (Projection) Snapshots (for long event streams) Anti-Patterns | Anti-Pattern | Fix | |--------------|-----| | Querying event store for reads | Build read models via projections | | No optimistic concurrency | Check expected version on append | | Deleting events | Events are immutable; use compensating events | | Projections coupled to write model | Projections consume events independently | | No snapshots for long streams | Snapshot every N events (e.g., 100) | Prod…