Infrastructure Engineer

Dex; Greater London; On-site; GBP 90,000 - 150,000; Full time

Job summary

Dex is partnering with a world-class trading infrastructure team in London to own the physical and virtual compute and networking estate powering live trading and settlement systems. You will configure bare-metal Linux servers, troubleshoot Cisco Nexus/Catalyst switches, and build Python automation for a microsecond-sensitive environment.

This role demands deep networking expertise and a strong automation mindset.

Qualifications

• 5+ years managing production Linux environments and enterprise network infrastructure.
• Deep TCP/IP knowledge with routing, subnetting and latency analysis.
• Hands-on with Cisco Nexus/Catalyst switches and data centre cabling.
• Python for automation and standard Git workflows.

Responsibilities

• Own and scale the physical and virtual network foundation across data centres to balance throughput and ultra-low latency.
• Serve as senior escalation point for production network anomalies, OS bottlenecks and hardware faults.
• Write Python automation to provision and configure switches, policies and server fleets.
• Instrument hosts and links with Prometheus, Grafana, and SNMP to detect microbursts.
• Plan zero-downtime maintenance and hardware upgrades across co-located sites.

Skills

Linux systems administration

Network troubleshooting

TCP/IP routing

Python scripting

On-call readiness

Tools

Cisco Nexus switches

Cisco 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.

Dex is an AI recruiter agent that helps you run your job search. Tell Dex your stack, seniority, and what you want to build. We will manage your applications and surface other opportunities that are a fit.

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.

Why apply through Dex

Trading infrastructure roles at top-tier market makers are tightly guarded, and distinguishing elite engineering cultures from chaotic crypto desks is hard from the outside. Applying through Dex skips agency gatekeepers and gives you direct, unvarnished insight into the team's stack, compensation, and production reality before you step into an interview. Sign up once, skip the cold applications, and get positioned straight in front of the hiring team.

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