Event Sourcing over CRUD for Audit Trail Compliance

The engineering team decided to replace standard CRUD with Event Sourcing for the financial transaction audit trail. Problem: database updates in PostgreSQL were overwriting previous states, making it impossible to provide compliance with full history (e.g., transaction #8821 status change). Alternatives: database triggers rejected (no business context). Event Sourcing selected with Kafka for immutable events and Postgres materialized views for reads. Reference: Martin Fowler Event Sourcing Pattern article. Code: Bob to implement event producers in src/services/transactionService.ts and consumer/store in src/events/eventStore.ts.