Polymarket Copy-Trading Bot (TypeScript)

Minimal bot that mirrors trades from one or more Polymarket traders, with spend limits and automatic cashout after resolution.

Deploy on Railway

Install

npm install
cp .env.example .env

Run

npm run build
npm run start

Simple config (the essentials)

In .env:

• PRIVATE_KEY: private key for the wallet linked to your Polymarket account (needed to sign orders).
• PROFILE_ADDRESS: the Polymarket address visible in your account (proxy/profile wallet).
• COPY_TRADERS: comma‑separated list of trader addresses to copy.
• MAX_DAILY_VOLUME_USD: daily USD cap for buys.
• MAX_POSITION_SIZE_USD: per‑position USD cap for buys.

Copy strategy (easy)

• COPY_STRATEGY: PERCENT_USD (default), PERCENT_SHARES, FIXED_USD, FIXED_SHARES
• COPY_RATIO: ratio for percent strategies (e.g. 0.25 = 25%)
• FIXED_TRADE_USD: fixed amount if FIXED_USD
• MIN_TRADE_USD, MAX_TRADE_USD
• COPY_SIDE: BUY, SELL, BOTH

Auto cashout (optional)

To auto‑redeem when a market is resolved:

• AUTO_REDEEM=true
• RPC_URL: Polygon RPC URL
• Local builder creds: BUILDER_API_KEY, BUILDER_API_SECRET, BUILDER_API_PASSPHRASE
  • or remote signer: BUILDER_SIGNING_URL, BUILDER_SIGNING_TOKEN

How to get Builder API keys

1. Open polymarket.com/settings?tab=builder.
2. Create a Builder Profile if needed, then click “+ Create New”.
3. You’ll get apiKey, secret, and passphrase (keep them private).

How to get your PRIVATE_KEY (Magic / email login)

1. Open https://reveal.magic.link/polymarket.
2. Confirm the warnings and reveal your private key.
3. Paste it into PRIVATE_KEY in your .env.

Advanced variables (explained, not required in .env)

These all have defaults in code. Only set them if you want overrides:

• CLOB_HOST (default: https://clob.polymarket.com): CLOB endpoint.
• DATA_API_HOST (default: https://data-api.polymarket.com): Data API endpoint.
• CHAIN_ID (default: 137): Polygon chain id.
• POLL_INTERVAL_MS (default: 5000): trade polling frequency.
• TRADE_LOOKBACK_SEC (default: 300): startup catch‑up window.
• STATE_FILE (default: ./data/state.json): local persistence file.
• MAX_SEEN_TRADES_AGE_SEC (default: 604800): retention for seen trades.
• CLOB_API_KEY, CLOB_API_SECRET, CLOB_API_PASSPHRASE: use if you want to avoid auto‑derivation at startup.
• RELAYER_URL (default: https://relayer-v2.polymarket.com): redeem relayer endpoint.
• RELAYER_TX_TYPE (default: PROXY): relayer transaction type.
• SIGNATURE_TYPE (default: 1): wallet signature type.
• FUNDER_ADDRESS: profile/funder address if needed (otherwise PROFILE_ADDRESS).

Polymarket address (clear)

Use the Polymarket address visible in your account (proxy/profile wallet):

• Put it in PROFILE_ADDRESS.
• You do not need to put your EOA address in .env.
• You still need the PRIVATE_KEY of the wallet linked to your Polymarket account to sign orders.

Minimal example

PRIVATE_KEY=0x...
PROFILE_ADDRESS=0x...   # Polymarket-visible address
COPY_TRADERS=0x123...,0x456...
MAX_DAILY_VOLUME_USD=200
MAX_POSITION_SIZE_USD=500
COPY_STRATEGY=PERCENT_USD
COPY_RATIO=0.25

Railway Deployment Notes

Railway makes it easy to host a long‑running bot. Deploy this repo, set env vars, and add a volume:

• Mount a volume at /data
• Set STATE_FILE=/data/state.json for persistence
• Set RAILPACK_NODE_VERSION=22 to force Node 22