Argent Financial Infrastructure

A developer-first financial infrastructure API, built for scale, immutability, and speed.

Argent is a modern financial infrastructure system engineered to provide a robust Ledger, Wallet, and Transaction Engine. Designed with strict immutability, idempotent transaction guarantees, and deep environment scoping, Argent allows businesses to securely manage multi-tenant financial data across sandbox and production environments.

⚠️ Note: This project is actively developed. It is fully dockerized and ready for local testing but has not yet been deployed to a live production environment.

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✨ Key Architectural Highlights

We engineered Argent to solve the hardest problems in financial tech: race conditions, data mutation, and environment bleed.

• Immutable Ledger Engine: Double-entry accounting where LedgerEntry records are completely immutable. Backed by PostgreSQL BEFORE UPDATE and BEFORE DELETE triggers to strictly enforce database-level immutability against malicious or accidental mutations.
• Robust Transaction Engine: A polymorphic Strategy Pattern implementation supporting Deposits, Withdrawals, Transfers, Refunds, and Adjustments. Features built-in idempotency to prevent duplicate charging.
• Multi-Environment Scoping: Strict separation of data between SANDBOX and PRODUCTION. The environment flows logically from Wallet → Account → LedgerEntry ensuring API keys can never access out-of-scope data.
• Role-Based Access Control (RBAC): Native JWT and API key authentication supporting OWNER, ADMIN, and DEVELOPER roles for multi-tenant organizational access.
• Caching & High Availability: Redis caching applied to balances to dramatically decrease DB load, coupled with smart cache invalidation upon ledger entry creation.

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🛠️ Technology Stack

Backend

• Java 21 & Spring Boot 3.4.1
• Spring Security (JWT + API Keys)
• Spring Data JPA & Hibernate
• Flyway (Database migrations)
• PostgreSQL 16 (Primary Datastore)
• Redis 7 (Caching Layer)
• RabbitMQ 3 (Event Messaging)

Frontend Dashboard

• React 18 (via Vite)
• TypeScript
• Tailwind CSS (Utility-first styling)
• Zustand (Global state management)
• TanStack Query (Server state & data fetching)

Infrastructure & Quality

• Docker & Docker Compose (Containerized micro-services)
• JUnit 5 / MockMvc / Testcontainers (180+ comprehensive backend tests)
• Vitest & React Testing Library (Frontend Component & Integration testing)

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🚀 Getting Started

Getting the entire Argent infrastructure running on your local machine takes less than 5 minutes. The environment is entirely containerized using Docker Compose.

Prerequisites

• Docker
• Docker Compose

Running the Stack

1. Clone the repository:

   git clone https://github.com/yourusername/argent.git
   cd argent

2. Spin up the infrastructure:

   # This will pull postgres, redis, rabbitmq, and build the backend/frontend containers
   docker-compose up --build -d

3. Verify running containers:

   docker-compose ps

4. Access the Application:

   • Frontend Dashboard: http://localhost:3000
   • Backend API: http://localhost:8080
   • RabbitMQ Management: http://localhost:15672 (u: argent, p: devpassword)

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🧪 Testing and Quality Assurance

Argent prioritizes extreme stability due to the critical nature of financial data.

• Backend: Over 180+ tests (Unit + Integration) covering the core Ledger and Transaction engines, asserting atomicity, isolation, and handling optimistic locking failures (409 Conflict). Run via ./gradlew test.
• Frontend: Component tests and full mocked routing integration tests utilizing vitest and jsdom.

🗺️ Roadmap (V2)

While V1 provides a comprehensive Dashboard and API for ledger and wallet management, future versions will implement:

• Webhook Subscriptions: Asynchronous notifications for balance thresholds and transaction status changes.
• Idempotency Keys: Client-provided UUID headers for exact API retry safety.
• Advanced Reporting: Exporting general ledgers in various financial formats.

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Argent is built by engineers passionate about highly resilient, developer-first tooling.