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How to Build an Exchange

Claudio, Ron, Pete

A US equities matching engine utilizes a deterministic, single-instance architecture to process three million messages per second while ensuring fair, latency-critical order execution across thousands of symbols. The system employs C++ and OCaml on a dedicated machine to replace complex distributed consensus with high-speed, single-threaded logic, allowing state machines to recover from failures within 30 to 60 seconds via message log replay. This design guarantees regulatory reproducibility and financial reliability by eliminating consensus overhead, enabling clients to achieve precise atomicity and global risk enforcement through simplified, high-throughput message sequencing.

Effective ML 2011 Harvard CS51 Part 2

Jane Street's engineering philosophy prioritizes explicit error handling, strict boilerplate avoidance, and managed complexity to ensure robust high-frequency trading systems. By leveraging OCaml's predictable performance and enforcing rigorous code review protocols alongside small, autonomous teams, the firm balances mathematical precision with human oversight in a hybrid trading model. This approach treats software development as a discipline of clarity and maintainability, where static typing and disciplined mutation control enable reliable operation in volatile markets.