Design, implement, and maintain market data feed handlers, optimize system performance, and collaborate with traders and engineers to ensure data integrity.
Job Description
Role Summary
We are looking for a Market Data Software Engineer to design, build, and optimize high-performance systems for processing and distributing real-time market data. This role is ideal for engineers who have hands-on experience developing market data feed handlers and a passion for writing high-performance C++ code.
Opportunities may be available from time to time in any location in which the business is based for suitable candidates. If you are interested in a career with Citadel, please share your details and we will contact you if there is a vacancy available.
Responsibilities:
Qualifications:
In accordance with applicable law, the base salary range for this role is $175,000 to $350,000.
In addition, the employee who fills this role will be eligible to participate in a discretionary incentive compensation program, as well as a wide array of benefit programs, such as medical and life insurance, retirement and tax-free savings plans, and access to other healthcare programs.
About Citadel Securities
Citadel Securities is a technology-driven, next-generation global market maker. We provide institutional and retail investors with world-class liquidity, competitive pricing and seamless front-to-back execution in a broad array of financial products. Our teams of engineers, traders and researchers harness leading-edge quantitative research and the accelerating power of compute, machine learning and AI to power our analytics and tackle the market's and our clients' most critical challenges. Together, we are forging the future of capital markets. For more information, visit citadelsecurities.com .
Role Summary
We are looking for a Market Data Software Engineer to design, build, and optimize high-performance systems for processing and distributing real-time market data. This role is ideal for engineers who have hands-on experience developing market data feed handlers and a passion for writing high-performance C++ code.
Opportunities may be available from time to time in any location in which the business is based for suitable candidates. If you are interested in a career with Citadel, please share your details and we will contact you if there is a vacancy available.
Responsibilities:
- Design, implement, and maintain market data feed handlers for equities, options, futures, FX, and other markets
- Integrate market data feeds into trading and analytics systems with a focus on throughput, latency, and reliability
- Analyze and optimize system performance at both the code and hardware levels
- Collaborate closely with traders, quantitative researchers, and infrastructure engineers to ensure timely, accurate data delivery
- Manage and monitor live market data systems, proactively identifying and resolving issues
- Continuously improve software deployment, monitoring, and recovery processes for mission-critical production systems
- Contribute to the design and evolution of the firm's market data architecture, including internal APIs and data distribution frameworks
- Develop, support, and maintain market data infrastructure applications such as republishers and capture systems
Qualifications:
- Deep experience in C++ with a passion for clean, performant code
- Experience with market data feed handler development
- Deep understanding of network programming and Linux systems internals
- A strong grasp of multithreading, concurrency, and distributed systems
- Curiosity to explore how things work and a drive to improve them
- Clear, thoughtful communication and the ability to thrive in a high ownership environment
- Bachelor's (or higher) degree in a Computer Science, Engineering or related technical field
In accordance with applicable law, the base salary range for this role is $175,000 to $350,000.
In addition, the employee who fills this role will be eligible to participate in a discretionary incentive compensation program, as well as a wide array of benefit programs, such as medical and life insurance, retirement and tax-free savings plans, and access to other healthcare programs.
About Citadel Securities
Citadel Securities is a technology-driven, next-generation global market maker. We provide institutional and retail investors with world-class liquidity, competitive pricing and seamless front-to-back execution in a broad array of financial products. Our teams of engineers, traders and researchers harness leading-edge quantitative research and the accelerating power of compute, machine learning and AI to power our analytics and tackle the market's and our clients' most critical challenges. Together, we are forging the future of capital markets. For more information, visit citadelsecurities.com .
Top Skills
C++
Distributed Systems
Linux
Multithreading
Citadel Securities London, England Office

120 London Wall, London, United Kingdom, EC2Y 5ET
Similar Jobs at Citadel Securities
Information Technology • Software • Financial Services
Design and optimize electronic trading platforms, develop pricing and risk-management libraries, and collaborate with research teams for custom software solutions.
Top Skills:
C++Python
Information Technology • Software • Financial Services
The Machine Learning Researcher will conduct research and development in machine learning for options trading, owning the full lifecycle from design to deployment, and leveraging large datasets to create impactful models.
Top Skills:
NumpyPythonPyTorch
Information Technology • Software • Financial Services
Interns will learn financial markets, develop trading strategies, analyze data, and collaborate with experienced traders to enhance trading tools and frameworks.
Top Skills:
AIComputersMachine Learning
What you need to know about the London Tech Scene
London isn't just a hub for established businesses; it's also a nursery for innovation. Boasting one of the most recognized fintech ecosystems in Europe, attracting billions in investments each year, London's success has made it a go-to destination for startups looking to make their mark. Top U.K. companies like Hoptin, Moneybox and Marshmallow have already made the city their base — yet fintech is just the beginning. From healthtech to renewable energy to cybersecurity and beyond, the city's startups are breaking new ground across a range of industries.


