Senior Software Engineer – Ultra Low Latenc

Citigroup Inc.; Singapore; On-site; SGD 220,000 - 300,000; Full time

Job summary

Citi is seeking a Senior Software Engineer – Ultra Low Latency Risk Engine Lead Developer to join the Equities Electronic Execution team in Singapore. You will own and optimize the real-time risk engine, ensuring microsecond‑level performance on the cash equities hot path and coordinating delivery across global centers.

You will mentor engineers, drive architecture decisions, and collaborate with product, quants, and infrastructure teams to deliver a scalable, low‑latency trading platform.

Qualifications

• 10+ years of software engineering experience in latency‑sensitive systems for cash equities electronic trading or similar.
• Strong, hands‑on expertise in Low Latency Java and/or C++ with multi‑threading and lock‑free data structures.
• Experience with Aeron, Solace or equivalent IPC frameworks for high‑throughput systems.
• Knowledge of NUMA, CPU core pinning/affinity and Linux kernel tuning for ultra low‑latency environments.

Responsibilities

• Design, develop, and deliver an ultra low‑latency risk engine for real‑time pre‑trade checks and exposure controls.
• Lead architecture decisions, mentor engineers, and coordinate across global centers.
• Collaborate with product, quants, infrastructure, and QA to ensure performance and resiliency.

Skills

Low Latency Java/C++

Multithreading

JVM performance tuning

C++

Java NIO

NUMA awareness

Education

Bachelor's degree in Computer Science or Engineering

Tools

Aeron

Solace

RDMA

Job description

Citi Equities Technology | Equities Electronic Execution (Electronic Trading)

Role Overview

Citi's Equities Technology organization is seeking a Senior Software Engineer – Ultra Low Latency Risk Engine Lead Developer to join the Equities Electronic Execution (Electronic Trading) technology team. This role is focused on the design, development, and delivery of Citi's next-generation low-latency Risk Engine for cash equities and its integration into the broader execution platform — encompassing the Centralised Position Service, Client Connectivity, Market Access layers, and high-throughput market data processing.

The engineer will own critical, latency-sensitive risk-checking components that sit directly in the cash equities trading hot path, ensuring pre-trade and real-time risk controls are enforced with microsecond-level performance while maintaining correctness and resiliency at scale. This is a hands‑on, deeply technical role that also carries leadership responsibilities — mentoring engineers, driving architecture decisions, and coordinating delivery across global development centers.

The person will collaborate closely with product development, quantitative research, technology infrastructure, production support, and QA teams, with close alignment to global strategy and cross-regional delivery (APAC, EMEA, NAM).

Responsibilities

Risk Engine & Core Development

• Design, develop, and maintain the ultra low-latency, in-line Risk Engine responsible for real-time pre-trade risk checks, position limits, and exposure controls across cash equities electronic execution flows.

• Architect and optimize high-performance, lock-minimal, multi-threaded components capable of processing risk decisions in the sub-microsecond to low-microsecond range.

• Integrate risk and position components with Client Connectivity, Market Access layers, and high-throughput market data feed handlers.

• Apply deep expertise in JVM performance tuning, memory management, garbage collection avoidance, and/or native (C++/Rust) performance engineering to eliminate latency outliers ("jitter") in the risk path.

• Perform system-level performance tuning to minimize end-to-end latency and jitter across the risk and execution path.

Qualifications

• 10+ years of overall software engineering experience, with substantial hands‑on experience building risk management, position‑keeping, or other latency‑critical systems for cash equities electronic trading or algorithmic trading platforms at a global investment bank or equivalent financial institution.

• Strong, hands‑on technical expertise in Low Latency Java and/or C++ (Rust a plus), including multi-threading, concurrency, lock‑free data structures, Java NIO, and JVM/GC performance tuning.

• Hands‑on experience with low-latency messaging and IPC frameworks such as Aeron, Solace, or equivalent shared‑memory/IPC technologies for building distributed, high-throughput trading systems.

• Demonstrated background in real‑time distributed risk management systems for cash equities flow products, including asynchronous, event‑driven architectures.

• Practical, hands‑on experience with NUMA‑aware design, CPU core pinning/affinity and isolation, Linux kernel/OS tuning, and low‑latency networking (kernel bypass, RDMA, or specialized NIC tuning) for ultra low‑latency, high‑throughput systems.

• Strong understanding of automated testing techniques, test‑driven development, and quality engineering practices for mission‑critical systems.

• Excellent communication skills, with the ability to present and grasp complex technical and risk concepts in a multicultural, cross‑regional environment, and to work effectively with globally distributed stakeholders (trading desks, quants, infrastructure, and support teams).

• Working knowledge of regional exchange microstructure and relevant regulatory regimes governing cash equities electronic trading and risk controls.

Education

• Bachelor's degree / University degree in Computer Science, Engineering, or a related field, or equivalent professional experience (e.g., Mechanical Engineering combined with a Diploma in Advanced Computing).

Job Family Group:

Technology

Job Family:

Applications Development

Time Type:

Full time

Most Relevant Skills

Please see the requirements listed above.

Other Relevant Skills

For complementary skills, please see above and/or contact the recruiter.

Citi is an equal opportunity employer, and qualified candidates will receive consideration without regard to their race, color, religion, sex, sexual orientation, gender identity, national origin, disability, status as a protected veteran, or any other characteristic protected by law.

If you are a person with a disability and need a reasonable accommodation to use our search tools and/or apply for a career opportunity review Accessibility at Citi. View Citi’s EEO Policy Statement and the Know Your Rights poster.