C++ Software Engineer – High‑Performance Trading Systems

About the role

Citadel Securities is seeking a C++ Software Engineer to design, build, and maintain high‑performance systems that power its global trading infrastructure. You will work in a fast‑paced environment where nanoseconds matter and where innovative solutions directly impact market‑making activities.

Key responsibilities

• Break down complex challenges and deliver clean, elegant solutions that drive real‑world outcomes.
• Design, develop, and sustain low‑latency, high‑throughput systems that form the backbone of the trading platform.
• Continuously optimize latency, reliability, and throughput in a distributed environment.
• Collaborate closely with traders, researchers, and fellow engineers to move ideas from concept to production.
• Own production code: monitor, support, and improve it on a daily basis.

Required profile

• Deep experience in C++ with a focus on clean, performant code.
• Strong understanding of multithreading, concurrency, and distributed systems.
• Curiosity to explore how systems work and a drive to improve them.
• Clear communication skills and ability to thrive in a high‑ownership environment.
• Bachelor’s (or higher) degree in Computer Science, Engineering, or a related field.
• Background in trading or finance is a plus but not required.

Required skills

• C++
• Multithreading
• Concurrency
• Distributed systems

What we offer

• Opportunity to work on cutting‑edge technology in a leading global market‑making firm.
• Relocation support for candidates moving to any of our listed global offices.
• Collaborative environment with top talent in finance, science, and technology.