Set Up Your Polymarket Arbitrage Scanner

What the Arb Scanner Does

PM-02 watches Polymarket and Kalshi simultaneously, every 3 minutes. When the same event is priced differently across platforms — and the gap is large enough to profit after fees — it fires a Telegram alert with exactly what to buy on which platform.

With AUTO_EXECUTE=true it places both legs simultaneously, locking in the profit before the window closes.

• 1

  Every 3 minutes

  Fetches all active markets from both Polymarket and Kalshi. Uses fuzzy AI matching to find the same event on both platforms.

• 2

  Calculates net profit after fees

  Accounts for Polymarket's ~2% maker fee and Kalshi's 7% profit fee. Only alerts on opportunities where net profit > your minimum (default 3¢).

• 3

  Fires Telegram alert

  Tells you exactly: buy YES on [platform] @ [price] + buy NO on [platform] @ [price]. Net profit: $X on $Y deployed.

• 4

  Optional auto-execute

  Places both legs simultaneously the moment the arb is detected. No manual action needed.

What You Need

Accounts

• Polymarket account with USDC funded — same as PM-01
• Kalshi account with USD funded — kalshi.com (US-regulated, takes 5 min)
• Telegram bot — same bot as PM-01 if you have it

Capital strategy

Unlike PM-01, arb requires capital on both platforms simultaneously. Split your capital between Polymarket and Kalshi. The scanner handles one side on each per arb.

Install & Configure

Unzip PM-02 and run the setup wizard:

copycd pm-02-arb-scanner
python3 setup.py

The wizard will ask for:

• Polymarket API Key, Secret, Passphrase, Private Key, Wallet address
• Kalshi API key — get from kalshi.com → Account → API Keys
• Telegram bot token + chat ID
• MIN_SPREAD — minimum net profit to alert (recommend 0.03)
• MAX_ARB_POSITION — max $ per side per arb (recommend 100-500)
• AUTO_EXECUTE — true/false (start false, go true when comfortable)

Test Your Connection

copypython3 src/test_connection.py

Expected output:

✓ Polymarket public API reachable
✓ CLOB API key valid
✓ Kalshi API key valid and markets reachable
✓ Telegram message sent — check your phone!
✓ POLYMARKET_API_KEY is set
✓ KALSHI_API_KEY is set

All checks passed. Ready to scan for arbs.

Dry Run — Watch It Find Arbs

copypython3 src/arb_scanner.py --dry-run

You'll see the scanner working in real time:

[CYCLE 1] 00:14:22
Fetching Polymarket... 187 markets
Fetching Kalshi... 143 markets
Matching markets... 31 pairs found

[DRY RUN] ARB FOUND
Polymarket: Will Fed cut 25bps? → YES @ 44¢
Kalshi:     Will Fed cut 25bps? → YES @ 37¢

Action: BUY YES on Kalshi @ 37¢ + BUY NO on Polymarket @ 56¢
Spread: 7¢ | Net profit after fees: $55 on $1000
Match score: 0.91

→ Would execute (dry run — skipped)

Next scan in 3 min.

Go Live + 24/7 Daemon

Drop the dry-run flag:

copypython3 src/arb_scanner.py

Install the 24/7 background service:

copy./scripts/setup_launchd.sh

Monitor the log:

copytail -f /tmp/arb_scanner.log