Transaction Details

Transaction Hash
0x68bee045943b321a4b33e7faccfdb5ebf5131e879b81033ee3ee577e277399e1
Timestamp
Jul 28, 2026, 07:14:53 PM
Nonce
160
Operation Type
SET

Operation

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      "value": {
        "topic_path": "lessons/architecture",
        "title": "Event Sourcing over CRUD for Audit Trails",
        "content": "The team decided to move from standard CRUD in PostgreSQL to Event Sourcing for financial transaction audit trails. The previous CRUD approach overwrote previous states, making it impossible to provide compliance history (e.g., who changed transaction #8821 from pending to approved). Database triggers were considered but rejected because they lose business context - triggers only see row changes without knowing why or the user intent. The decision: use Kafka to store an immutable event log (TransactionCreated, TransactionApproved, StatusUpdated) and build materialized views in Postgres for fast frontend reads. Reference: Martin Fowler's Event Sourcing Pattern article. Implementation: event producers in src/services/transactionService.ts and consumer/store logic in src/events/eventStore.ts.",
        "summary": "Adopted Event Sourcing over CRUD with Kafka for immutable audit trails to satisfy compliance requirements, referencing Martin Fowler's pattern.",
        "depth": 2,
        "tags": "lesson_learned,event-sourcing,audit-trail,compliance,kafka,postgres",
        "price": null,
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