System; Linux Engineer Quant Finance

Quantitative Trading Firm | London (hybrid)

A world‑leading quant trading firm is hiring a Systems (Linux) Engineer to support, maintain and enhance the Linux infrastructure that its 24/7 trading operation runs on. This is deep infrastructure work at the sharp end — ultra‑low‑latency, high‑frequency, real‑time systems where performance is measured in microseconds and custom OS builds are the norm.

You’ll sit close to the action: keeping the Linux environment healthy day‑to‑day (emergency response, change execution, troubleshooting, performance tuning), while building the automation that provisions, configures and monitors thousands of Linux servers. You’ll manage core services (DHCP, LDAP, DNS, NFS) across on‑prem, hosted data centres and public cloud, and partner with the Cloud Architecture team to design and refine trading systems running in complex brownfield AWS environments purpose‑built for low latency.

• Day‑to‑day support of a critical Linux trading environment — emergency response, change execution, troubleshooting and resolving performance issues
• Developing and refining tools to automate provisioning, configuration and monitoring at the scale of thousands of servers
• Managing core services (DHCP, LDAP, DNS, NFS) across on‑prem, hosted DCs and public cloud
• Working with Cloud Architecture to review existing and implement new designs for trading systems on AWS
• Improving the performance, resilience, availability and observability of existing cloud environments
• Participating in a rotational on‑call schedule (including early mornings and weekends)

• 5+ years administering an advanced Linux environment, with deep knowledge of Linux internals
• Strong server‑side networking (protocols, configuration)
• Proven automation/monitoring tool development; configuration management with Ansible
• Expert Bash and good Python for scripting and automation
• Solid grasp of source control, CI/CD and automated deployment
• Strong AWS expertise (EC2, ENA, VPC, ELB, Direct Connect, S3, EBS) in a low‑latency performance‑engineering context — including how Linux and kernel components are tuned for EC2 and the AWS network
• A methodical problem‑solver who communicates well and drives things to completion

• Open‑source or personal projects
• AWS Dev Ops Engineer Professional or AWS Advanced Networking certifications

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