Exness Trading Platform

A microservices-based trading platform built with Node.js, featuring real-time trade execution through Kafka message streaming and dual-layer state management. 1

Architecture

The platform uses a microservices architecture with three core components:

• Backend Service (Express.js on port 5000): HTTP API gateway handling authentication, request orchestration, and database operations
• Engine Service (Node.js): Isolated trade processing with in-memory state for low-latency execution
• Message Broker (Apache Kafka): Asynchronous inter-service communication with correlation IDs for request-response patterns 2

Tech Stack

• Runtime: Node.js with TypeScript
• Backend Framework: Express.js
• Message Queue: Apache Kafka
• Database: TimescaleDB (PostgreSQL)
• Cache: Redis (for sessions and magic links)
• Authentication: JWT with magic link signup 3

Key Features

Trade Operations

• Open/close trades with leverage support
• Real-time price updates from external poller
• Automatic liquidation price calculation
• In-memory order book for fast execution 4

Authentication

• Passwordless magic link authentication
• JWT-based session management
• Protected trade and balance endpoints 5

Data Management

• In-Memory State (Engine): latestPrice, openOrders, userBalance for sub-millisecond access
• Persistent Storage (TimescaleDB): User accounts, asset definitions, trade history 6

API Endpoints

Endpoint	Method	Auth	Description
/api/v1/signup	POST	None	Generate magic link
/api/v1/signin/post	GET	None	Validate magic link
/api/v1/trade/create	POST	JWT	Open new trade
/api/v1/trade/close	POST	JWT	Close existing trade
/api/v1/balance/usd	GET	JWT	Query USD balance
/api/v1/balance/	GET	JWT	Query total balance

Request Response Pattern

Message Flow

The system implements a synchronous request-response pattern over Kafka using correlation IDs:

1. Backend generates unique ID and publishes command to trade-price topic
2. Engine consumes message, executes business logic, publishes result to acknowledge topic with same ID
3. Backend consumer matches ID and resolves the waiting promise (5-second timeout) 7

Engine Task Routing

The engine routes messages based on data.task field:

• createUser: Initialize user with 5000 USD balance
• create: Open trade (validate balance, calculate liquidation)
• close: Close trade (calculate PnL, update balance)
• balance/usdBalance: Return current balance

Price updates from external poller (identified by from: "poller") update the latestPrice object without acknowledgment. 8

Getting Started

Prerequisites

• Node.js
• Kafka broker
• TimescaleDB instance
• Redis server

Environment Variables

KAFKA_BROKER=<kafka-broker-url>
TIMESCALE_CONNECTION_STRING=<postgres-connection-string>

Running Services

Backend:

cd backend
npm install
npm start

Engine:

cd engine
npm install
npm start

Supported Assets

The platform currently supports three trading pairs (hardcoded on initialization):

• SOL_USDC (Solana)
• ETH_USDC (Ethereum)
• BTC_USDC (Bitcoin) 9

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🤝 Open Source & Contributions

This project is open source and welcomes contributions from developers, students, and enthusiasts interested in trading infrastructure, distributed systems, and Kafka-based architectures.

🧭 How to Contribute

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1. Fork the repository
2. Create a new branch for your feature or fix

git checkout -b feature/your-feature-name

3. Commit your changes

git commit -m "Add: your feature description"

4. Push to your fork

git push origin feature/your-feature-name

5. Submit a Pull Request (PR) with a clear explanation of your change 10

🧾 Contribution Guidelines

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1. Follow consistent code formatting (Prettier / ESLint recommended)
2. Add comments where logic is complex or business-critical
3. Use TypeScript types and interfaces wherever possible
4. Write descriptive commit messages
5. Test your changes before creating a PR

Your name will be added to the Contributors section once your PR is merged 🎉 11

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👨‍💻 Author

Akash Raj MERN Stack & Backend Developer

🪪 License

This project is licensed under the MIT License — free to use, modify, and distribute with attribution. 12