event-store-design

To design an event store for scalable systems, you model domain events using append-only semantics, per-stream and global ordering, and versioned events with optimistic concurrency to ensure auditability and reconstructable state.

The best way to persist event-sourced data involves evaluating technologies like PostgreSQL for relational schemas or Kafka for streaming. Compare them against EventStoreDB or DynamoDB to craft schemas, migrations, and guardrails tailored to your throughput needs.

Implement idempotent writes and optimistic concurrency in an event store by enforcing append-only, versioned event semantics per stream. This prevents duplicate events and manages concurrent updates without locking the entire event stream.

You need snapshot strategies for event-sourced aggregates when rebuilding state from a long event stream becomes a performance bottleneck. Snapshots periodically persist the current aggregate state, reducing the number of events that must be replayed during reconstruction.

DynamoDB works for building an event store by carefully designing partition keys for per-stream ordering and using global tables or secondary indexes for broader ordering requirements. It requires specific schema guardrails to maintain append-only semantics.

Append-only event storage is used instead of traditional CRUD operations to provide a complete, auditable history of state changes. It enables reconstructable domain events and supports reliable subscriptions for building read models and projections.