Polymarket Copy Trading Bot

A production-grade, real-time copy trading system for Polymarket, designed to automatically mirror trades from selected wallets with high reliability, low latency, and robust risk controls. Built in TypeScript with Node.js, the bot integrates directly with Polymarket's Central Limit Order Book (CLOB) API for institutional-level execution.

---

Support the Project

If you find this bot helpful and profitable, we'd greatly appreciate your support! Consider sending 10% of your profits to help maintain and improve this project:

Wallet Address: 4GNqE1cn7wRZyGsv8MHHMf8C6QSc3Mk3fWYkLdTNf7EX

Your support helps us continue developing and maintaining this tool. Thank you! 🙏

---

Overview

The Polymarket Copy Trading Bot continuously monitors target wallets and replicates their trading activity according to configurable risk parameters. It is designed for professional deployment, supporting automated trade execution, precise order handling, and comprehensive logging.

Core Capabilities

• Real-Time Trade Monitoring – Continuously fetches and processes trades from target wallets
• Automatic Trade Execution – Mirrors buy/sell/merge operations with intelligent position matching
• Advanced Risk Management – Balance-based position sizing and retry mechanisms
• Flexible Order Execution – Supports FOK (Fill-or-Kill) order types
• MongoDB Integration – Persistent tracking of trades and positions
• Multi-Outcome Compatibility – Works seamlessly with binary and multi-outcome markets

---

⚠️ Past performance does not guarantee future results. Trading prediction markets involves significant risk. Use responsibly and only with capital you can afford to lose.

---

📊 Trading History & Performance

target address : https://polymarket.com/@k9Q2mX4L8A7ZP3R

The bot has demonstrated profitable performance in testing. Below is a screenshot showing the profit/loss progression over a test period:

Updated profit : 3 / 11 / 2026

]

Test Results Summary:

• Initial Profit: $28.08 (Dec 20, 2025 6:00 PM)
• Final Profit: $923.41 (Dec 22, 2025 6:00 AM)
• Time Period: ~36 hours
• Performance: Consistent upward trend with significant profit accumulation
• Growth: Over 3,200% increase in profit during the test period

---

Note: These results are from a test environment. Real-world performance may vary based on market conditions, wallet selection, and configuration parameters.

---

System Architecture

Technology Stack

• Runtime: Node.js 18+
• Language: TypeScript (v5.7+)
• Blockchain: Polygon (Ethereum-compatible L2)
• Web3: Ethers.js v5
• Database: MongoDB
• APIs:
  • @polymarket/clob-client - Polymarket CLOB trading client
  • Polymarket Data API - For fetching activities and positions
• Utilities: Axios, Mongoose, Ora (spinners)

High-Level Flow

Polymarket Data API (HTTP Polling)
        ↓
Trade Monitor (Fetches & Validates Trades)
        ↓
MongoDB (Stores Trade History)
        ↓
Trade Executor (Reads Pending Trades)
        ↓
Position Analysis (Compares Wallets)
        ↓
CLOB Client (Executes Orders)
        ↓
Order Execution (Buy/Sell/Merge Strategies)

---

Installation

Prerequisites

• Node.js 18+ and npm
• MongoDB (running locally or remote)
• Polygon Wallet funded with USDC
• Polymarket Account with API access

Setup Steps

1. Clone the repository:

git clone https://github.com/BlackSkyorg/polymarket-copytrading-bot.git
cd Polymarket-copy-trading-bot-2025-12

2. Install dependencies:

npm install

3. Create environment configuration:

Create a .env file in the root directory:

# Target user wallet address to copy trades from
USER_ADDRESS=0xYourTargetWalletAddress

# Your wallet address (proxy wallet) that will execute trades
PROXY_WALLET=0xYourProxyWalletAddress

# Private key of your proxy wallet (64 hex characters, NO 0x prefix)
PRIVATE_KEY=your_private_key_here

# Polymarket CLOB API URLs
CLOB_HTTP_URL=https://clob.polymarket.com
CLOB_WS_URL=wss://clob-ws.polymarket.com

# MongoDB connection string
MONGO_URI=mongodb://localhost:27017/polymarket_copytrading

# Polygon RPC URL (for checking balances)
RPC_URL=https://polygon-rpc.com

# USDC contract address on Polygon
USDC_CONTRACT_ADDRESS=0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174

# Optional: Configuration defaults
FETCH_INTERVAL=1
TOO_OLD_TIMESTAMP=24
RETRY_LIMIT=3

4. Start MongoDB:

# Windows
net start MongoDB

# Linux/Mac
sudo systemctl start mongod
# or
mongod

5. Start the bot:

# Development mode (with ts-node)
npm run dev

# Or build and run
npm run build
npm start

On first launch, API credentials are automatically created/derived from your wallet.

---

⚙️ Configuration Reference

Variable	Description	Required
USER_ADDRESS	Target wallet address to copy trades from	Yes
PROXY_WALLET	Your wallet address that executes trades	Yes
PRIVATE_KEY	Your wallet private key (64 hex, no 0x)	Yes
CLOB_HTTP_URL	Polymarket CLOB HTTP API endpoint	Yes
CLOB_WS_URL	Polymarket WebSocket endpoint	Yes
MONGO_URI	MongoDB connection string	Yes
RPC_URL	Polygon RPC endpoint	Yes
USDC_CONTRACT_ADDRESS	USDC token contract on Polygon	Yes
FETCH_INTERVAL	Trade monitoring interval (seconds)	No (default: 1)
TOO_OLD_TIMESTAMP	Ignore trades older than X hours	No (default: 24)
RETRY_LIMIT	Maximum retry attempts for failed trades	No (default: 3)

---

Usage

Start Copy Trading

npm run dev

The bot will:

1. Connect to MongoDB
2. Initialize CLOB client and create/derive API keys
3. Start trade monitor (fetches trades every X seconds)
4. Start trade executor (processes pending trades)
5. Monitor target wallet and execute copy trades automatically

Expected Output

When running successfully, you should see:

MongoDB connected
Target User Wallet address is: 0x...
My Wallet address is: 0x...
API Key created/derived
Trade Monitor is running every 1 seconds
Executing Copy Trading
Waiting for new transactions...

Trade Execution Flow

1. Monitor: Fetches user activities from Polymarket API
2. Filter: Identifies new TRADE type activities
3. Store: Saves new trades to MongoDB
4. Execute: Reads pending trades and determines action (buy/sell/merge)
5. Match: Compares positions between target wallet and your wallet
6. Trade: Executes orders via CLOB client
7. Update: Marks trades as processed in database

---

Execution Logic

Trade Lifecycle

1. Fetch Activities: Monitor target wallet via Polymarket Data API
2. Filter Trades: Identify TRADE type activities only
3. Check Duplicates: Verify trade hasn't been processed before
4. Validate Timestamp: Ignore trades older than configured threshold
5. Save to Database: Store new trades in MongoDB
6. Read Pending Trades: Query database for unprocessed trades
7. Fetch Positions: Get current positions for both wallets
8. Get Balances: Check USDC balances for both wallets
9. Determine Condition: Decide on buy/sell/merge based on positions
10. Execute Order: Place order via CLOB client using appropriate strategy
11. Update Status: Mark trade as processed in database

Trading Strategies

• Buy Strategy: When target wallet buys, calculate position size based on balance ratio
• Sell Strategy: When target wallet sells, match the sell proportionally
• Merge Strategy: When target wallet closes position but you still hold, sell your position
• Error Handling: Retry failed orders up to RETRY_LIMIT, then mark as failed

---

Project Structure

src/
 ├── index.ts                 # Main entry point
 ├── config/
 │   ├── db.ts                # MongoDB connection
 │   └── env.ts               # Environment variables
 ├── services/
 │   ├── tradeMonitor.ts      # Monitors target wallet trades
 │   ├── tradeExecutor.ts     # Executes copy trades
 │   └── createClobClient.ts # Alternative CLOB client (unused)
 ├── utils/
 │   ├── createClobClient.ts  # CLOB client initialization
 │   ├── fetchData.ts         # HTTP data fetching
 │   ├── getMyBalance.ts      # USDC balance checker
 │   ├── postOrder.ts         # Order execution logic
 │   └── spinner.ts           # Terminal spinner
 ├── models/
 │   └── userHistory.ts       # MongoDB schemas
 ├── interfaces/
 │   └── User.ts              # TypeScript interfaces
 └── test/
     └── test.ts              # Test utilities

---

Logging & Monitoring

• Trade detection and execution
• Balance and allowance checks
• Redemption outcomes
• Structured logs for debugging and audits

Log levels: info, success, warning, error

---

Risk Disclosure

• Copy trading amplifies both profits and losses
• Liquidity and slippage risks apply
• Gas fees incurred on every transaction
• WebSocket or API outages may impact execution

Best Practices:

• Start with low multipliers
• Enforce strict max order sizes
• Monitor balances regularly
• Test using dry-run modes

---

🛠️ Development

# Type check
npm run build

# Run in development mode
npm run dev

# Lint code
npm run lint

# Fix linting issues
npm run lint:fix

# Format code
npm run format

---

Strategy Development Story

This copy trading bot was developed as part of a comprehensive Polymarket trading strategy system. Development began in December 2025, focusing on automated trade execution and position management.

Key Features

• Real-time trade monitoring and execution
• Intelligent position matching and sizing
• Automatic retry mechanisms for failed orders
• MongoDB-based trade history tracking
• Support for multiple market types

---

Troubleshooting

Common Issues

1. "USER_ADDRESS is not defined"

   • Check your .env file exists and has all required variables

2. "MongoDB connection error"

   • Ensure MongoDB is running
   • Verify MONGO_URI is correct

3. "Cannot find module '@polymarket/clob-client'"

   • Run npm install to install dependencies

4. "invalid hexlify value"

   • Check PRIVATE_KEY is 64 hex characters without 0x prefix

5. "API Key creation failed"

   • Verify PRIVATE_KEY matches PROXY_WALLET
   • Ensure wallet has proper permissions

Testing

Before running in production:

1. Monitor first few trades carefully
2. Verify MongoDB is storing trades correctly
3. Check order execution logs

---

License

ISC

---

Disclaimer: This software is provided as-is without warranties. Trading prediction markets involves substantial risk. Use responsibly and only with capital you can afford to lose. Past performance does not guarantee future results.