Engineering · CLOB API

Wire Polymarket directly into your trading stack.

If you have an existing quant system and you want Polymarket as a venue alongside your other markets, we build native CLOB API integrations. EIP-712 order signing, proxy-wallet support, websocket book streams, rate-limit handling. Technically: we wrap the CLOB REST + WS endpoints in a typed client compatible with your existing OMS, with retry/back-off and order lifecycle telemetry.

100 req/min
Polymarket CLOB public rate limit
src: Polymarket docs May 2026
60 orders/min
Polymarket authenticated order submission limit
src: Polymarket docs May 2026
$0.001-0.005
Polygon gas cost per CLOB trade
src: 30-day averages
EIP-712
Order signing standard - built-in to our client
src: Polymarket spec
How it works

What an integration looks like.

Four layers, each independently testable and swappable.

01 · AUTH

Proxy-wallet model with optional EOA mode. We handle the L1/L2 funding flow, USDC approvals, and key rotation policies.

02 · DATA

Markets metadata, orderbook snapshots, fills, and resolutions - REST + WS streams normalized into your event bus. Reconnect/replay built-in.

03 · ORDERS

Limit, FOK, IOC, market - all signed and submitted via EIP-712. Includes order lifecycle (placed/filled/canceled/expired) emitted to your telemetry.

04 · OPS

Rate-limit accounting, backoff, dead-letter for failed requests, structured logs. The kind of work nobody wants to write but everybody needs.

Config

Drop-in client - Python example.

Typed wrapper, async streams, normalized events. Same API surface for Polymarket and Kalshi in our SDK.

client.py config
# Python - typed CLOB client wrapper
from predikted.clob import ClobClient, OrderType

client = ClobClient(
    host="https://clob.polymarket.com",
    chain_id=137,                # Polygon mainnet
    proxy_wallet=True,
)

# Book snapshot
book = client.get_orderbook(token_id="0xabc…")
mid = (book.best_bid + book.best_ask) / 2

# Place a signed limit order
order = client.place_order(
    token_id="0xabc…",
    side="BUY",
    price=0.49,
    size_usdc=500,
    order_type=OrderType.GTC,
)

# Subscribe to your fills
async for event in client.stream_fills(wallet=client.account):
    metrics.observe(event)
Honest framing

Things to know before you wire funds.

i
Rate limits are conservative for a reason.

Polymarket's 100 req/min public endpoint is shared. If you're polling, you'll hit it. We default to websocket streams for book data and rate-account your authenticated calls.

i
Proxy wallets vs EOA - pick one.

Proxy wallets give a smoother UX but add an indirection layer to debug. EOAs are simpler but cost more per setup. We default to proxy unless you have a specific reason otherwise.

!
USDC approvals expire (sort of).

USDC is approved per spender. We surface the approval state in your dashboard so you don't get a surprise 'transfer failed' at 3am.

×
Don't share private keys with us. Ever.

Our integration runs on infra you own. We deliver code; you deploy with your keys. If someone says 'just send the seed', they're an arnaque.

Starting points

Stacks we've integrated with.

Where Polymarket CLOB plugs into your existing system.

In-house OMS / EMS Direct event bus integration

Most common: you have a Kafka/RabbitMQ event bus

Most common: you have a Kafka/RabbitMQ event bus. We hook the CLOB client into it as a venue.

NautilusTrader / Hummingbot Strategy framework adapter

Open-source quant frameworks

Open-source quant frameworks. We ship adapters that expose Polymarket as a venue inside the framework's abstractions.

Spreadsheet / notebook desk REST wrapper for analysts

Quant analysts driving execution from notebooks

Quant analysts driving execution from notebooks. We ship a thin REST wrapper they can call from Python directly.

Budget bracket

Where this typically lands.

Client library only
$8k-$18k · 2-3 weeks

Typed Python or TypeScript SDK. You deploy in your infra.

  • Typed client (PY or TS)
  • Order placement + cancel + status
  • WS book + fills streams
  • 30-day warranty
Get started

Wire Polymarket into your stack.

Tell us your OMS / event bus / language. We'll come back with an integration spec - typically two pages, costed line by line.