Low Latency Trading Infrastructure Engineer

Citi • Irving, TX

5d • $125,600 - $188,400

About The Position

Citi is hiring a Low Latency Trading Infrastructure Engineer for its Global Equity Markets technology organization. The role designs, delivers, and sustains ultra-low-latency infrastructure for electronic trading, combining hardware engineering, financial markets technology, and performance optimization. The engineer is responsible for deterministic performance across the trading stack, from bare-metal compute and operating-system tuning to networking, market-data distribution, circuits, and exchange colocation. The role works closely with application development teams, trading desks, Risk, InfoSec, Compliance, vendors, exchanges, and colocation facility partners, while meeting security, resiliency, audit, and regulatory requirements.

The position covers low-latency compute and network architecture, hardware and firmware standards, benchmarking and telemetry, colocation and exchange connectivity, certification and deployment, automation, infrastructure monitoring, lifecycle management, and Kubernetes operations. Work may involve air-gapped or network-segmented environments, stringent change and rollback processes, and time-sensitive troubleshooting during live market hours. The engineer also contributes to incident management, root-cause analysis, regulatory documentation, procurement, vendor coordination, and colocation buildouts, and must be willing to support off-hours maintenance and rapid incident response during market-critical periods.

The role is based in Jacksonville, Florida. The listed full-time salary range is $125,600–$188,400. Citi may also provide eligible employees discretionary and formulaic incentive and retention awards. Benefits include medical, dental, and vision coverage; 401(k); life, accident, and disability insurance; wellness programs; vacation and sick leave; and paid holidays. Offerings may vary by jurisdiction, job level, and date of hire.

Requirements

• At least 6 years of hands-on low-latency infrastructure engineering experience in electronic trading, capital markets, hedge funds, trading venues, or equivalent high-performance financial technology environments.
• Hands-on experience building and operating exchange colocation environments for equities or multi-asset electronic trading, including physical rack management, cross-connect provisioning, and circuit validation.
• Deep expertise in low-latency network architecture, ultra-low-latency switching, multicast market-data distribution, and Precision Time Protocol (PTP) implementation and synchronization.
• Advanced Linux systems engineering proficiency in RHEL or equivalent distributions, including kernel tuning, CPU pinning and isolation, NUMA optimization, IRQ affinity, C-state/P-state management, and huge-pages configuration.
• Hands-on experience with kernel-bypass and packet-acceleration technologies such as DPDK, XDP, Solarflare OpenOnload, and FPGA-based NIC solutions, with demonstrated ability to reduce stack-level latency to sub-microsecond levels.
• Proficiency in Python, Bash, or equivalent scripting languages, including tooling for benchmarking, telemetry collection, and infrastructure provisioning in air-gapped or tightly controlled environments.
• Strong experience with Ansible, Terraform, or Puppet for bare-metal provisioning, firmware management, and repeatable deployment pipelines in trading-sensitive environments.
• Hands-on experience designing and executing CI/CD pipelines with Jenkins, GitLab CI/CD, GitHub Actions, or ArgoCD, including infrastructure-as-code build, test, and deployment automation.
• Experience with Kubernetes or other container orchestration platforms, including deployment, scaling, node affinity configuration, and low-latency workload scheduling.
• Proficiency with InfiniBand, RoCE, and multicast networking applied to market-data distribution and inter-system communication.
• Experience with low-level telemetry and monitoring, including Wireshark or tcpdump packet analysis, hardware performance counters, and tick-to-trade latency measurement frameworks.
• Strong understanding of modern low-latency hardware, NICs, and FPGA-enabled compute environments, including experience evaluating and benchmarking hardware from relevant vendors.
• Familiarity with exchange connectivity rules, CAT requirements, MiFID II time-synchronization standards, and internal change-control and compliance frameworks for trading infrastructure.
• Meticulous documentation habits and strong written communication skills for change requests, incident reports, and certification approval packages.
• Experience supporting hardware procurement, vendor coordination, colocation buildouts, and telecom processes in a financial-services context.
• Bachelor's degree in Computer Science, Electrical Engineering, Information Technology, or a related technical discipline, or equivalent practical experience in a highly specialized low-latency or high-performance computing environment.
• Willingness to support off-hours maintenance windows and rapid incident response during market-critical periods.

Nice To Haves

• Experience with OpenShift or Amazon EKS; these are identified as preferred Kubernetes platforms.

Responsibilities

• Design low-latency compute topologies using bare-metal servers, NICs, kernel-bypass technologies, and FPGA and colocation hardware.
• Evaluate CPU microarchitecture, NUMA topology, cache behavior, and memory bandwidth for trading workloads.
• Define hardware and firmware standards with vendors, and maintain custom server build patterns for the low-latency trading platform.
• Establish and enforce low-latency Linux, Windows, and microservice infrastructure standards, including OS optimization, CPU isolation, NUMA optimization, interrupt tuning, and deterministic performance engineering.
• Build benchmarking harnesses for tick-to-trade latency, jitter, and throughput; analyze hardware, firmware, and BIOS settings; and correlate results with trading telemetry to validate production readiness.
• Analyze packet captures and latency telemetry across the trading stack.
• Architect and deliver high-performance colocation environments connecting exchange venues, market-data providers, and internal trading systems.
• Implement ultra-low-latency Layer 1 and Layer 2 network configurations.
• Execute certification test plans for hardware, firmware, and OS/kernel builds, and maintain audit-ready certification documentation.
• Coordinate with Risk, InfoSec, and exchange and venue technical teams on colocation and vendor certification, including CAT and MiFID II requirements for time synchronization, monitoring, and reporting.
• Provision and deploy infrastructure in air-gapped or network-segmented environments, manage approved offline or controlled image and firmware distribution, and apply change-management and rollback procedures.
• Deploy and support external-client and exchange connectivity circuits, including cross-connect provisioning and handoff validation at specialized and colocated data centers.
• Lead bare-metal automation, deployment pipelines, and infrastructure-as-code practices using tools such as Ansible, Terraform, and Puppet.
• Manage and configure Active Directory, ISA, DNS, PTP, remote-access solutions, and infrastructure management and monitoring technologies.
• Monitor compute health, latency drift, and hardware degradation using low-level telemetry tools.
• Manage hardware lifecycle refresh planning, end-of-life firmware tracking, and vendor support contract coordination.
• Troubleshoot hardware, operating-system, and network-stack issues under time-sensitive, high-impact conditions, including during live market hours.
• Manage Kubernetes cluster operations and workload orchestration for trading-adjacent microservice infrastructure.
• Implement and maintain high-speed interconnects, including InfiniBand, RoCE, and multicast networking protocols.
• Collaborate with application development and support teams to optimize end-to-end trading latency and infrastructure determinism.
• Participate in incident management and resiliency efforts, including post-incident documentation and root-cause analysis.
• Partner with software delivery teams, enterprise technology, and trading functions throughout platform delivery and deployment.
• Produce documentation for audits and regulatory review, including change requests, incident reports, and certification approval packages.
• Communicate engineering requirements and infrastructure risks to Risk, InfoSec, and Compliance partners.
• Work with vendors, exchange providers, hardware manufacturers, and colocation facility operators to optimize resiliency and performance.
• Support hardware procurement, vendor engagement, colocation buildouts, and telecom contract processes as an individual technical contributor.
• Support off-hours maintenance windows and rapid incident response during market-critical periods.

Benefits

• Medical insurance
• Dental insurance
• Vision insurance
• 401(k)
• Life, accident, and disability insurance
• Wellness programs
• Paid vacation
• Paid sick leave
• Paid holidays
• Discretionary and formulaic incentive and retention awards for eligible employees

What This Job Offers

• Job Type: Full-time
• Career Level: Senior