Consistency Patterns in Event-Driven Architecture

Distributed systems have a dirty secret. Your message broker swears the domain event is published — others are already listening, already reacting to this new order. But then, in a split second, your database rolls back. A constraint violation. Something breaks. And now the entire system knows about an order that never actually existed.

This talk covers the patterns that prevent that chaos: the Dual Write problem, Outbox and Inbox patterns for consistency between database and event stream, idempotent consumers, and Sagas — Orchestration and Choreography.

You'll leave knowing which pattern solves which problem, when to use each, and what you're really trading off with eventual consistency