Networking & Security Engineer

Capula Investment Management LLP; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

Capula Investment Management LLP in London is seeking a hands-on Infrastructure & Security Engineer to own security architecture, server and network domains, and to strengthen the firm’s security posture against evolving threats including AI-driven risks. The role blends proactive security ownership with infrastructure delivery on-site five days a week.

You will lead security operations, monitor events, drive hardening across Windows, Linux, and network devices, implement secure designs from day

Qualifications

• 7+ years in infrastructure, networking and security roles.
• Hands-on with Windows Server and Linux environments.
• Strong networking knowledge and Cisco experience.
• Experience implementing security controls: patching, hardening, IAM, endpoint protection.

Responsibilities

• Lead the security operations function: threat detection, incident response, vulnerability management end-to-end.
• Monitor, triage, and respond to security events across the environment with awareness of AI-driven attack vectors.
• Drive security hardening across servers, endpoints, network devices, and cloud-adjacent systems.
• Design and implement secure infrastructure solutions with security baked in from start.
• Conduct regular vulnerability assessments and pentesting; remediate findings promptly.
• Manage security tooling: SIEM, EDR, firewalls, IDS/IPS, endpoint protection platforms.
• Act as escalation point for security incidents across 2nd/3rd line; guide resolution.
• Support network infrastructure (firewalls, switches, VPNs, wireless) with security-focused config.
• Collaborate with infra teams to embed security into project delivery and BAU processes.
• Develop and maintain incident response playbooks, SOPs, architecture diagrams, runbooks.
• Stay current on threat landscape and recommend improvements.

Skills

Security operations

Threat detection

Incident response

Vulnerability management

SIEM

EDR

Firewalls

IDS/IPS

Endpoint protection

Windows Server

Linux

Networking

TCP/IP

VLANs

VPNs

DNS

DHCP

Cisco

Patch management

System hardening

Identity and access management

Cyber security principles

Virtualization

VMware

SAN/NAS

Scripting

PowerShell

Bash

Financial services experience

Communication

BAU coordination

On-call rotation

Job description

We are seeking a hands‑on Infrastructure & Security Engineer with deep expertise across security architecture, server, and network domains. Security is the core priority of this role. The successful candidate will take a leading part in strengthening and evolving the firm's security posture in response to an increasingly sophisticated threat landscape, including emerging risks associated with AI.

This is a technically demanding role that combines proactive security ownership with infrastructure delivery. The successful candidate will act as a security‑first thinker across everything they touch, from day‑to‑day operations through to strategic infrastructure design, and will be expected to drive meaningful improvements to the firm's defensive capabilities.

This role is office‑based and requires five days per week on‑site presence.

Key Responsibilities

• Lead the firm's security operations function, owning threat detection, incident response, and vulnerability management end‑to‑end
• Monitor, triage, and respond to security events across the environment, including log analysis, anomaly detection, and threat hunting, with a strong awareness of modern and AI‑enabled attack vectors
• Own and drive security hardening across all infrastructure — servers, endpoints, network devices, and cloud‑adjacent systems — ensuring consistent application of best practices and compliance with security policies
• Design and implement secure infrastructure solutions, embedding security requirements from the outset rather than retrofitting them
• Conduct regular vulnerability assessments and penetration testing exercises, prioritising and remediating findings in a timely manner
• Manage and continuously improve security tooling, including SIEM, EDR, firewalls, IDS/IPS, and endpoint protection platforms
• Act as the escalation point for security‑related incidents across 2nd and 3rd line, providing expert guidance and driving resolution
• Support and maintain network infrastructure including firewalls, switches, VPNs, and wireless systems (primarily Cisco‑based), with a security lens on all configuration and change
• Operate across Windows and Linux (Red Hat/CentOS) environments, ensuring both are maintained to a consistent security baseline
• Collaborate with infrastructure and technology teams to embed security into project delivery and BAU processes
• Develop and maintain security documentation including incident response playbooks, SOPs, architecture diagrams, and runbooks
• Stay current with the evolving threat landscape, bringing proactive recommendations to improve the firm’s security posture over time
• Participate in an on‑call rotation to support critical systems and respond to security incidents outside business hours

• Minimum 7+ years’ experience in infrastructure, networking, and security roles
• Strong hands‑on experience with Windows Server and Linux (Red Hat/CentOS)
• Solid networking knowledge, including TCP/IP, VLANs, VPNs, DNS, DHCP, with practical experience in Cisco environments
• Demonstrated experience implementing and supporting security controls, including:
• Patch management and system hardening
• Endpoint protection and monitoring
• Identity and access management
• Good understanding of cyber security principles, including modern threat landscapes and evolving risks (e.g. automation and AI‑driven attack vectors)
• Experience with virtualisation (VMware) and enterprise storage (SAN/NAS)
• Scripting or automation experience (e.g. PowerShell, Bash) is advantageous
• Experience in financial services or regulated environments is preferred
• Strong troubleshooting skills with a structured and analytical approach
• Able to balance BAU responsibilities with project delivery effectively
• A thoughtful and forward‑looking mindset, with the ability to identify risks and propose improvements
• Clear and confident communicator, able to engage with both technical and non‑technical stakeholders
• Self‑motivated, accountable, and willing to take ownership of issues end‑to‑end
• Collaborative and adaptable, with a practical and solutions‑focused approach