Order Matching Engine

Learn how Roxom’s matching engine processes orders during live trading and handles market-hours reopenings.

Roxom’s matching engine continuously processes and executes orders based on their price, priority, and timing. Execution rules differ slightly between continuous (24/7) and explicitly designated market-hours contracts.

Continuous Matching (24/7 Contracts): Contracts trading continuously (24/7) match orders in real-time without interruption. Incoming orders immediately match against the order book:

• Buy orders match against the lowest available asks.
• Sell orders match against the highest available bids.

Matching continues seamlessly around the clock until the incoming order fully executes or no further matches exist.

Limited Matching During Closed Sessions (Market-hours contracts only): For contracts explicitly designated as market-hours only, matching behavior outside of designated hours is limited:

• Limit orders can still enter the book and immediately match against existing resting orders.
• Market orders cannot be placed and will be rejected outside trading hours.
• Conditional orders (stops, stop-limits, etc.) will not trigger outside market hours but remain pending activation at market open.

This structure allows liquidity-taking during off-hours without risking forced executions or triggering conditional orders at potentially unfavorable prices.

Opening Sequence (Market-hours contracts only): Upon reopening after a closed session, Roxom immediately resumes trading:

1. The matching engine first checks the opening Mark Price and activates any conditional orders (stops, stop-limits, etc.) whose trigger conditions are met, placing them into the order book.
2. Immediately after conditional orders are activated, continuous matching resumes for all order types, including market orders.

There is no opening auction. Trading begins immediately, restoring full functionality.