Polymarket Backend

A prediction market backend built with TypeScript, Express.js, Prisma, and PostgreSQL.

Features

Authentication & Users

• JWT-based authentication
• User registration and login
• User profile management
• Balance tracking
• Leaderboard system

Markets

• Create and update prediction markets (admin only)
• Binary outcome markets (YES/NO)
• Market categories (Sports, Esports)
• Market search by title
• Lock betting before resolution
• Resolve markets with outcome

Betting System

• Place bets on market outcomes
• Dynamic odds calculation based on betting pool
• Automatic payout distribution on market resolution
• Betting history tracking

Transactions

• Track all financial transactions
• Transaction types: BET_PLACED, BET_WON, DEPOSIT, WITHDRAW
• Transaction history per user

Tech Stack

• Runtime: Node.js with TypeScript
• Framework: Express.js
• Database: PostgreSQL with Prisma ORM
• Validation: Zod
• Authentication: JWT (jsonwebtoken)
• Security: bcrypt for password hashing

API Endpoints

Users

• POST /api/v1/users/signup - Register new user
• POST /api/v1/users/signin - User login
• GET /api/v1/users/me - Get current user
• GET /api/v1/users/leaderboard - Get winning leaderboard

Markets

• POST /api/v1/markets/create - Create market (admin)
• PUT /api/v1/markets/update/:id - Update market (admin)
• GET /api/v1/markets/getallmarkets - List all markets
• GET /api/v1/markets/getmarket/:id - Get market by ID
• GET /api/v1/markets/openmarkets - Get open markets
• GET /api/v1/markets/getmarketsbycatagory/:category - Filter by category
• GET /api/v1/markets/search?title= - Search markets
• POST /api/v1/markets/lockbets/:id - Lock market (admin)
• POST /api/v1/markets/resolvemarket/:id - Resolve market (admin)

Bets

• POST /api/v1/bets/placebets - Place a bet
• GET /api/v1/bets/getallbets - Get user's bets
• GET /api/v1/bets/getallbetsmarket/:id - Get user's bets for a market

Transactions

• GET /api/v1/transactions/getalltransactions - Get user's transactions

Setup

1. Install dependencies:

npm install

2. Set up environment variables in .env:

DATABASE_URL="postgresql://user:password@localhost:5432/polymarket"
JWT_SECRET="your-secret-key-min-32-chars"
PORT="3005"

3. Run database migrations:

npx prisma migrate dev

4. Build and run:

npm run build
npm run dev

Database Schema

• User: Stores user accounts with email, password, balance
• Market: Prediction markets with outcomes, odds, and metadata
• Bets: User bets with amount, outcome choice, and locked-in odds
• Transactions: Financial transaction history

Current Implementation Notes

• Initial user balance: 10,000 units
• Odds calculation: Dynamic based on total betting pool
• Market outcomes: Binary (YES/NO)
• All monetary values in smallest unit (cents)