Resonate External System of Record Pattern (TypeScript)

Overview

The External System of Record pattern enables consistent state across multiple systems without distributed transactions. By designating one system as the "system of record" (source of truth) and treating others as "systems of reference" (cached/staged data), you can maintain consistency through careful ordering of writes and reads.

Core principle: Write to the system of record last. Read from the system of record first. Use Resonate's durable execution to guarantee eventual completion and automatic recovery.

Mental Model

WITHOUT TRANSACTIONS: