Quickstart

From nothing to reading markets, placing an order and streaming your account.

Note

Build against a demo exchange. Demo balances are not real money; production is.

Prerequisites

• Python 3.9 or newer (python3 --version)
• An API key for the exchange you are building against: a key ID and an Ed25519 private key. Environments lists the exchanges and where to get a key.

Walkthrough

Install the SDK

pip install stx-python

Save your key

Save the private key as a file, for example ~/.stx/demo.pem, then create ~/.stx/credentials with a [default] profile. Set region and env to the exchange the key belongs to; the values are on Environments.

[default]
region   = us
env      = demo
key_id   = your-key-id
key_file = ~/.stx/demo.pem

Environment variables and keyword arguments work too; see Authentication.

Make your first call

from stx import STX

with STX() as client:
    me = client.me()
    print("user", me.user_id, "account", me.account_id, "scope", me.scope)

scope is read_only or read_write; placing orders needs read_write.

Read some markets

from stx import STX

with STX() as client:
    page = client.markets(status="open", limit=5)
    for m in page:
        bid = m.bids[0].price if m.bids else "-"
        offer = m.offers[0].price if m.offers else "-"
        print(f"{m.symbol:<50} bid {bid:>8} offer {offer:>8} pays {m.max_price}")
    print("next cursor:", page.cursor)

Prices are dollar strings ("0.4200"). A winning contract pays the market’s max_price.

Place and cancel an order

from stx import STX

with STX() as client:
    market = next(
        m
        for m in client.iter_markets(
            status="open", trading=True, sort_by="event_start", sort_direction="desc"
        )
        if m.event_status == "scheduled"
    )
    order = client.place_order(market.market_id, "buy", "limit", price="0.01", quantity="1")
    print("placed", order.id, order.status, order.price, order.quantity)
    print("cancel", client.cancel_order(order.id).status)

A 1-cent buy for one contract, cancelled straight away.

Stream your orders

import asyncio

from stx import AsyncSTX


async def main():
    async with AsyncSTX() as client:
        async with client.websocket() as ws:
            orders = await ws.orders()
            snapshot = await orders.wait_snapshot()
            print("open orders:", len(snapshot["all_orders"]["orders"]))


asyncio.run(main())

Next

• Trading: batch orders, cancel many or all, expiration, cancel-on-disconnect
• WebSockets: every channel
• Errors & retries