Start by clarifying requirements and constraints, then design a high-level architecture that separates order management, routing logic, and third-party integrations. Focus on reliability, idempotency, and fault tolerance, and discuss trade-offs between consistency and availability.
Pro tip: Emphasize idempotency and exactly-once processing to prevent duplicate orders, and discuss how you would handle partial failures when routing to multiple matching engines.
Ask about expected throughput, latency, supported order types, and consistency requirements. Understand the number and types of third-party matching engines.
Outline components: API gateway, order service, routing service, and adapters for each matching engine. Consider using a message queue for decoupling and reliability.
Design how orders are routed to one or more engines based on rules like liquidity, fees, or client preference. Discuss smart order routing and fallback strategies.
Ensure idempotent order submission, handle timeouts and retries, and manage state reconciliation. Use distributed transactions or sagas if needed.
Discuss trade-offs between latency and consistency, and how to scale horizontally. Consider monitoring, logging, and alerting for production readiness.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.