Infrastructure Engineer

Dex; Greater London; On-site; GBP 120,000 - 180,000; Full time

Job summary

Dex partners with a premier algorithmic market maker to hire a senior Linux and network engineer. You will own the physical and virtual compute and networking estate powering live trading and settlement systems, configuring bare-metal Linux servers and co-located data centres.

You will write Python automation for provisioning, monitor with Prometheus and Grafana, and act as the escalation point for latency, packet loss, and hardware faults across global estates.

Qualifications

• 5+ years managing production Linux environments and enterprise networks.
• Strong TCP/IP, routing, latency, loss, jitter troubleshooting.
• Hands-on with Cisco Nexus/Catalyst switches and data center hardware.
• Python for automation with Git workflows.
• Willingness to participate in out-of-hours/on-call rotations.

Responsibilities

• Own and scale the physical and virtual network foundation across global data centres, balancing throughput and ultra-low latency.
• Serve as the senior escalation point for production network anomalies, OS bottlenecks, and hardware faults across live trading estates.
• Write Python automation to provision, configure, and audit switches, routing policies, and server fleets with minimal manual work.
• Instrument hosts, links, and switches with Prometheus, Grafana, and SNMP to detect microbursts and degradation.
• Plan and execute zero-downtime maintenance windows, hardware upgrades, and cabling overhauls across distributed co-location sites.

Skills

Linux administration

Network engineering

Python scripting

Latency troubleshooting

On-call rotation

Tools

Cisco Nexus

Catalyst switches

Prometheus

Grafana

SNMP

tcpdump

Wireshark

Job description

This role is with one of Dex's trusted partner companies. We work closely with their teams to truly understand their culture, goals, and what they're looking for, so we can match you with the right opportunity and give you context about the role before you commit to a process.

The role

One of the world's premier algorithmic market makers in digital assets, deploying proprietary high-frequency strategies across hundreds of global venues around the clock. Backed by top-tier investors and operating at sub-millisecond execution speeds, their infrastructure underpins billions in daily volume with zero tolerance for packet loss or downtime.

You will own the physical and virtual compute and networking estate that powers live trading and mission-critical settlement systems. This is not a cloud-dashboard sysadmin job or corporate IT support; you will be configuring bare-metal Linux servers, troubleshooting Cisco switches in co-located data centres, and building Python automation for an environment where every microsecond counts.

The work

• Own and scale the physical and virtual network foundation across global data centres, balancing raw throughput against ultra-low latency.
• Serve as the senior escalation point for production network anomalies, OS bottlenecks, and hardware faults across live trading estates.
• Write Python automation to provision, configure, and audit switches, routing policies, and server fleets without manual overhead.
• Instrument hosts, links, and switches with Prometheus, Grafana, and SNMP to catch microbursts and degradation before traders feel it.
• Plan and execute zero-downtime maintenance windows, hardware upgrades, and cabling overhauls across distributed co-location sites.

What You Bring

• 5+ years managing production Linux environments and enterprise network infrastructure in high-reliability or trading settings.
• Deep, packet-level understanding of TCP/IP, routing, and subnetting, with proven skill triaging latency, loss, and jitter using tcpdump, Wireshark, and traceroute.
• Hands-on experience deploying, cabling, and configuring Cisco Nexus or Catalyst switches, ACLs, and physical server hardware in data centre environments.
• Proficiency in Python for systems and network automation, backed by standard Git workflows.
• Availability to participate in an out-of-hours and weekend on-call rotation for production maintenance and critical incidents.

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