Event Sourcing in Financial Systems: Why Ledger Integrity Depends on It
Traditional CRUD-based systems lose information. When you update a database record, the previous state is gone. In financial systems, this is unacceptable. Regulators require a complete audit trail. Accountants need to know the state of a transaction at any point in time. Dispute resolution requires reconstructing what happened, not just what the current state is. Event sourcing stores every change to system state as an immutable event. The current state is derived by replaying events. The full history is preserved by definition. For financial systems, event sourcing is not an architectural preference — it is a compliance requirement. ...