Ultra-Low Latency Trading Systems Engineer

Citi; Jacksonville (FL); On-site; USD 126,000 - 188,000; Full time

Job summary

Citi is seeking a Lead Low Latency Infrastructure Engineer in Jacksonville, FL, to design and maintain the ultra-fast trading infrastructure. You will optimize tick-to-trade latency across BIOS, NIC configurations, and OS-level settings while ensuring security and regulatory compliance.

You will collaborate with trading desks, risk teams, and vendor partners to deliver deterministic performance and scalable infrastructure in high-stakes market environments.

Qualifications

• 6+ years in low-latency infrastructure engineering in electronic trading or similar.
• Hands-on experience with exchange colocation environments and market data distribution.
• Deep Linux and kernel-bypass tech knowledge for tick-to-trade performance.

Responsibilities

• Design and operate ultra-low latency compute topologies and co-located hardware.
• Tune BIOS, NICs, and OS for deterministic performance in trading workloads.
• Architect high-performance colocation and connect to exchange venues.
• Lead automation pipelines (Ansible/Terraform/Puppet) for bare-metal delivery.
• Coordinate with Risk, InfoSec, and Compliance for regulatory standards.
• Develop telemetry and benchmarking to measure microsecond-scale latency.
• Provide incident response and root-cause analysis for market hours.

Skills

Low latency infrastructure

Kubernetes operations

Kernel tuning

CPU pinning & isolation

NUMA optimization

IRQ affinity & C-state/P-state

DPDK / XDP / Solarflare OpenOnload

FPGA-based NICs

InfiniBand / RoCE networking

Cross-connect provisioning

Automation tooling (Ansible, Terraform

Puppet

Scripting (Python, Bash)

CI/CD pipelines (Jenkins, GitLab)

Linux system engineering (RHEL)

Vendor coordination (Dell, HPE, Mellan

Education

Bachelor's degree in Computer Science or related field

Tools

Dell OpenManage Enterprise

HPE OneView

Lenovo LXCA

Dell/HP/Mellanox NICs & firmware

Wireshark / tcpdump

Job description

Citi is seeking a Lead Low Latency Infrastructure Engineer in Jacksonville, FL, to design and maintain the ultra-fast trading infrastructure. You will optimize tick-to-trade latency across BIOS, NIC configurations, and OS-level settings while ensuring security and regulatory compliance.

You will collaborate with trading desks, risk teams, and vendor partners to deliver deterministic performance and scalable infrastructure in high-stakes market environments.