domain-fintech:ledger-design

To design a double-entry ledger system, you need to define a structured chart of accounts, establish AR/AP sub-ledgers, and implement immutable audit trails using hash chains to ensure financial data integrity and regulatory compliance.

An immutable audit trail is implemented using hash chains and reversal patterns to create secure, tamper-evident transaction histories. This ensures that financial records cannot be altered without detection, satisfying regulatory compliance requirements.

Reconciling sub-ledgers with the general ledger involves ensuring that AR, AP, and other sub-ledgers accurately match their corresponding GL control accounts. This process maintains accurate financial record-keeping and prevents data discrepancies in your accounting software.

You can choose between running balances (cached) and computed balances (derived) for ledger balance calculation, or adopt a hybrid approach. The right balance calculation strategy depends on your system's performance requirements and data query patterns.

Event sourcing applies the ledger-as-event-log pattern to a double-entry ledger, creating a complete, replayable audit trail of financial transactions. This approach ensures that all state changes are captured as immutable events for accurate historical reconstruction.

Building a fintech ledger does not require a specific framework, but it does require strict adherence to core accounting principles like debit-credit balance, entry immutability, and sub-ledger to GL reconciliation to ensure tamper-evident transaction histories.