Trading Platform

A full-stack cryptocurrency trading platform with real-time order matching and WebSocket updates.

This project was built as a technical assignment for a software engineering position. See REQUIREMENTS.md for the full specification.

Tech Stack

Layer	Technology
Backend	Laravel 12, PHP 8.3, Sanctum
Frontend	Vue 3 (Composition API), TypeScript, Pinia, Tailwind CSS 4
Database	PostgreSQL 16
Real-time	Soketi (Pusher-compatible WebSocket)
Queue/Cache	Redis 7
Web Server	Caddy 2

Features

• User authentication with Laravel Sanctum
• USD balance and crypto asset management (BTC, ETH)
• Limit order placement (buy/sell)
• Order matching engine with price-time priority
• 1.5% commission on trades (deducted from buyer)
• Real-time balance and order updates via WebSocket
• Order cancellation with fund/asset release

Quick Start

git clone <repository-url>
cd trading_platform
make build
make setup

Open http://localhost:5173 in your browser.

Available Commands

make help          # Show all commands
make up            # Start containers
make down          # Stop containers
make logs s=app    # View logs for a service
make shell         # Open shell in app container
make test          # Run tests
make fresh         # Reset database with seeders
make tinker        # Laravel REPL

API Endpoints

Method	Endpoint	Description
POST	/api/login	Authenticate user
POST	/api/logout	Logout user
GET	/api/profile	Get balance and assets
GET	/api/symbols	List tradeable symbols
GET	/api/orders?symbol=BTC	Get orderbook
POST	/api/orders	Place limit order
POST	/api/orders/{id}/cancel	Cancel order

Architecture

trading_platform/
├── api/                    # Laravel backend
│   ├── app/
│   │   ├── Actions/        # PlaceBuyOrder, PlaceSellOrder, MatchOrder, CancelOrder
│   │   ├── Events/         # OrderMatched (broadcast)
│   │   └── Models/         # User, Asset, Order, Trade, Symbol
│   └── config/trading.php  # Commission rate config
├── frontend/               # Vue.js frontend
│   ├── src/
│   │   ├── stores/         # Pinia stores (auth, trading)
│   │   └── views/          # Wallet, Orders, Trade views
└── docker-compose.yml      # All services

Order Matching Logic

Buy order: Matches with lowest-priced sell order where sell.price <= buy.price

Sell order: Matches with highest-priced buy order where buy.price >= sell.price

Commission: 1.5% deducted from buyer's received assets

Real-time Events

Orders broadcast to private channels (private-user.{id}) when matched:

• Balance updates
• Asset updates
• Order status changes

Development

# Backend tests
make test

# Frontend dev server (already running via Docker)
# Or run locally:
cd frontend && npm run dev

# Frontend tests
cd frontend && npm test

Environment

Copy example env files for local development:

cp api/.env.example api/.env
cp frontend/.env.example frontend/.env

License

MIT