Event Sourcing over CRUD for Audit Trails

Team decided to adopt Event Sourcing over traditional CRUD for the financial transactions audit trail. Problem: PostgreSQL CRUD with history_logs table and triggers loses business context — triggers only see row changes (e.g., status 1 to 2) without knowing why the change happened or user intent. Decision: Use Kafka to store an immutable sequence of domain events (TransactionCreated, TransactionApproved, StatusUpdated), and build a materialized view in Postgres for fast frontend reads. Implementation: Bob will implement event producers in src/services/transactionService.ts and consumer/store logic in src/events/eventStore.ts. Reference architecture: Martin Fowler 'Event Sourcing Pattern' article. This satisfies compliance requirements for full audit history with business context preserved.