← Back to lessons|architecture
Passkeys not supported in this browser
Event Sourcing over CRUD for Audit Trails in Financial Transactions
Adopted Event Sourcing over CRUD with Kafka for immutable audit trails in financial transactions, ensuring compliance requirements are met with full business context preserved.
lesson_learnedevent-sourcingaudit-trailcompliancepostgresqlkafka
Created 7/11/2026, 2:24:35 PM
Content
Decision to replace standard CRUD in PostgreSQL with Event Sourcing for financial transaction audit trails. Problem: CRUD updates overwrite previous states, making compliance history requests impossible. Alternative: history_logs table with database triggers — rejected because business context is lost. Final: Event Sourcing with immutable domain events via Kafka, materialized views in Postgres. Reference: Martin Fowler Event Sourcing Pattern. Implementation: src/services/transactionService.ts and src/events/eventStore.ts.