Xchng is a distributed crypto exchange monorepo built with performance and simplicity in mind.

Architecture

• apps/web: Next.js frontend with Better Auth integration.
• apps/api-server: Express API for order placement, communicating with the engine via Redis.
• apps/engine: High-performance matching engine worker.
• apps/db-worker: Subscribes to engine events and persists state to PostgreSQL.
• apps/ws: Standalone WebSocket service for real-time orderbook, trade, and ticker updates.
• packages/database: Raw pg pool connection for shared DB access.
• packages/exchange-store: Direct SQL-based store for all trading logic.
• packages/redis: Shared Redis client and channel constants.

Getting Started

1. Environment Setup

Copy the example environment file and fill in required values:

cp .env.example .env

2. Infrastructure Startup

Start the required services (PostgreSQL and Redis) using Docker:

pnpm infra:up

3. Database Initialization

Initialize the database schema with the provided SQL file:

pnpm db:setup

4. Run Development Server

Start all services in development mode:

pnpm dev

Maintenance Commands

Command	Action
pnpm infra:up	Starts Postgres & Redis containers in background
pnpm infra:down	Stops and removes infrastructure containers
pnpm db:setup	Re-initializes database schema (caution: does not drop existing data if using IF NOT EXISTS, but meant for setup)
pnpm build	Builds all packages and apps
pnpm check-types	Runs type checks across the entire monorepo