OpenPit Python documentation

OpenPit is an embeddable pre-trade risk SDK for Python applications that need policy-driven checks before an order leaves the process. Typical embeddings are trading systems, broker gateways, strategy runtimes, and test harnesses that need deterministic order-admission logic next to the caller.

The Python package is openpit. It exposes a risk engine with explicit synchronization policies, strong domain value types, order and execution-report models, built-in policies, and Python interfaces for project-specific checks.

Main use case

Use OpenPit when an application has to decide whether an order can be sent to a downstream venue or broker adapter. A typical flow:

  1. Build an openpit.Engine during application startup.

  2. Register built-in and custom policies.

  3. Submit each openpit.Order to the start stage.

  4. Execute the deferred main stage when the caller is ready.

  5. Commit or roll back the returned reservation.

  6. Feed openpit.ExecutionReport objects back into the engine.

Pre-trade decisions stay explicit: policy rejects are returned as business results, while invalid API usage remains an exception.

Key features

  • Two-stage pre-trade pipeline with explicit request and reservation handles.

  • Built-in order validation, rate limit, P&L kill switch, and size-limit policies.

  • Python interfaces for start-stage, main-stage, and account-adjustment policies.

  • Exact decimal-backed domain value types for prices, quantities, P&L, fees, cash flow, and position sizes.

  • Extensible Python order and execution-report models that can carry integration-specific metadata into policy callbacks.

  • Atomic account-adjustment batches with policy rejects and rollback mutations.

Minimal quickstart

import openpit
import openpit.pretrade.policies

engine = (
    openpit.Engine.builder()
    .no_sync()
    .builtin(
        openpit.pretrade.policies.build_order_validation(),
    )
    .build()
)

order = openpit.Order(
    operation=openpit.OrderOperation(
        instrument=openpit.Instrument("AAPL", "USD"),
        account_id=openpit.param.AccountId.from_int(99224416),
        side=openpit.param.Side.BUY,
        trade_amount=openpit.param.TradeAmount.quantity("100"),
        price=openpit.param.Price("185"),
    ),
)

result = engine.execute_pre_trade(order=order)
if not result:
    raise RuntimeError(result.rejects[0].reason)

try:
    # Send the order to the venue here.
    result.reservation.commit()
except Exception:
    result.reservation.rollback()
    raise

Getting started

User guide

Examples

API reference