Design Crypto Order Routing
Company: Coinbase
Role: Software Engineer
Category: System Design
Difficulty: hard
Interview Round: Onsite
Design the order-placement system for a cryptocurrency trading product.
The product lets users place, cancel, and track crypto buy and sell orders. Your company does not run the matching engine itself. Instead, it routes orders to one or more third-party matching venues or exchanges. Different venues may expose different APIs or protocols.
Design a system that supports:
- Market and limit orders.
- Order submission, cancellation, and status tracking.
- Multiple external matching venues.
- Balance checks and fund reservation before order submission.
- Execution reports, partial fills, failed orders, and reconciliation.
- High availability, correctness, auditability, and low-latency order handling.
Discuss APIs, data model, core services, order state transitions, routing logic, failure handling, scaling, observability, and trade-offs.
Quick Answer: This question evaluates a candidate's ability to design a scalable, low-latency order-routing and execution tracking system that integrates multiple external matching venues, focusing on distributed systems, API design, state machines, fault tolerance, consistency, reconciliation, and observability within the trading/cryptocurrency domain.