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"content": "Team discussed database strategy for financial transaction audit compliance. Currently using standard CRUD in PostgreSQL, but updates overwrite previous states making it impossible to provide history for compliance audits (e.g., who changed transaction #8821 status from pending to approved). Alternatives considered: (1) Database triggers with a history_logs table — rejected because business context is lost; triggers only see row changes, not why the change happened or user intent. (2) Event Sourcing — adopted. Instead of storing current state in a mutable table, store a sequence of immutable domain events (TransactionCreated, TransactionApproved, StatusUpdated) via Kafka, with materialized views in Postgres for fast frontend reads. Reference: Martin Fowler's Event Sourcing Pattern article. Implementation: event producers in src/services/transactionService.ts, consumer/store logic in src/events/eventStore.ts.",
"summary": "Adopt Event Sourcing over CRUD with Kafka for immutable event logging to satisfy compliance audit requirements, with Postgres materialized views for read performance.",
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