Coinbase·Software Engineer·Onsite - System Design / Architecture·Staff

Staff

May 2026

Summary

Coinbase EM system design round. One question, pretty open-ended, and I spent the first few minutes just trying to scope it before diving in.

Questions Asked (1)

Design the backend system for a cryptocurrency exchange platform like Coinbase.

System DesignTechnical Trade-offsData Modeling

Author's notes

I started with the wallet and transaction layer because that felt like the core, but I probably should've asked more clarifying questions first.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and scale, then focus on the core trading engine and order matching, followed by data consistency and security. Emphasize trade-offs between consistency, availability, and latency, and how you would handle high throughput and fault tolerance.

Pro tip: Highlight the importance of idempotency and exactly-once processing in financial transactions, and mention how you would use a distributed ledger or event sourcing to maintain an audit trail.

1. Clarify Requirements and Scale

Ask about expected throughput (e.g., transactions per second), latency requirements, supported cryptocurrencies, and regulatory constraints. Define functional and non-functional requirements.

2. High-Level Architecture

Outline the main components: API gateway, order matching engine, wallet service, ledger, and market data service. Discuss how they interact and the data flow.

3. Deep Dive into Core Components

Focus on the order matching engine (e.g., using in-memory data structures, concurrency control) and the ledger (e.g., double-entry bookkeeping, ACID transactions). Discuss data partitioning and replication.

4. Address Scalability and Reliability

Explain how to scale horizontally (e.g., sharding by trading pair), ensure fault tolerance (e.g., replication, failover), and handle peak loads (e.g., rate limiting, queueing).

5. Security and Compliance

Discuss security measures (encryption, cold storage, DDoS protection) and compliance (KYC/AML, audit logs). Mention how to prevent double-spending and ensure data integrity.

Key Points to Mention

Order matching engine design: use of limit order book, priority queues, and concurrency control (e.g., actor model or locks).
Data consistency: ACID vs BASE, use of distributed transactions or saga patterns for cross-service operations.
Scalability: sharding by trading pair, read replicas, caching market data, and using message queues for asynchronous processing.
Security: encryption at rest and in transit, cold/hot wallet separation, multi-signature wallets, and regular security audits.
Fault tolerance: replication, leader election, and idempotent operations to handle retries.
Regulatory compliance: KYC/AML integration, transaction monitoring, and audit trails using immutable logs.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.