ledger-api

Backend financial ledger demonstrating immutable double-entry records, atomic transfers, idempotent requests, and JWT-based authentication.

Click to zoom

Overview

ledger-api is a backend financial ledger. Balances are calculated from immutable ledger entries instead of directly mutating a stored balance.

Capabilities

• User registration, login, and logout.
• JWT and HTTP-only cookie authentication with token blacklist-based logout.
• Account creation and retrieval.
• Balance derived from immutable double-entry debit and credit records.
• Atomic transfers using MongoDB sessions and transactions.
• Idempotency keys to prevent duplicate transactions.
• Transaction state tracking.
• A privileged system-user endpoint for initial funds.

Supporting technologies

bcryptjs, cookie-parser, dotenv, and MongoDB sessions/transactions.

Availability

The project is complete and its source is available on GitHub. There is no live deployment.