IT Security Engineer

Janestreet; Greater London; On-site; GBP 70,000 - 120,000; Full time

Job summary

Jane Street is seeking an Infrastructure Security Engineer with a strong Windows engineering background to secure our IT platforms globally. You will write code and automation (PowerShell, Python) and integrate security products via APIs, focusing on strategic controls and scalable solutions.

You will coordinate security initiatives across IT, influence broader teams, and drive vulnerability management while building secure automation workflows for Windows environments.

Qualifications

• Proficient in securing Windows OS platforms and resolving complex issues.
• Hands-on experience with security technologies for Windows: application control, host-based firewalls, auditing, and encryption.
• Experience administering endpoint security and vulnerability management including antivirus, EDR, patching.
• Knowledge of OS hardening, PAM, and vulnerability mitigation.
• Understand TTPs and countermeasures.
• Familiar with Windows core services (AD/EntraID, PKI).
• Automation mindset to build scalable, repeatable security practices.
• Understand security tooling and APIs.
• Fluent in English.

Responsibilities

• Design, test, implement and document strategic security controls.
• Coordinate and deliver security solutions across IT platforms.
• Automate intelligent workflows to improve security tooling and processes.
• Secure internal IT and remote working platforms through hands-on work and consultancy.
• Build scalable security controls and drive vulnerability management initiatives.

Skills

Windows security

EDR

Vulnerability management

PowerShell

Python

Automation

Threat TTPs

PAM

AD/EntraID

APIs

English fluency

Tools

PowerShell

Python

Security APIs

Job description

About the Position

We are looking for an Infrastructure Security Engineer with a strong Windows engineering background and practical exposure to modern platform security controls to help our global team secure Jane Street's IT platforms. In this role, you'll need strong judgement and discerning taste to prioritise potentially complex and extensive remediation efforts. You'll help decide where we focus our resources, providing technical advice and making decisions on behalf of the group where needed. We're looking for builders: people who spend their time writing code and automation (e.g. PowerShell modules, Python) and integrating security products via their APIs, rather than primarily configuring and operating the tools themselves.

In this role, you will proactively propose, design, test, implement and document strategic security controls. You will coordinate and deliver security solutions across our IT platforms while identifying opportunities to further automate intelligent workflows. You will help secure internal IT and remote working platforms through a combination of hands-on technical work, consultancy and security influence to the wider IT team. This role will encompass a range of responsibilities, including building security controls that scale, investigating emerging threats, developing new security tooling and driving vulnerability management initiatives.

This position sits within our IT Engineering group, a highly dedicated team of engineers who monitor and manage our environment across a physical/virtual computing landscape that spans three continents. Your analytical thinking and expertise will be invaluable as we support the daily work of our colleagues and keep our systems operating at the highest standard.

About You

• Proficient in securing Windows OS platforms and resolving complex technical issues in a fast-moving environment
• Have hands-on experience utilising integrated security technologies for safeguarding Windows operating systems, including application control, host-based firewalls, auditing and event monitoring and disk encryption
• Skilled in administering endpoint security and vulnerability management solutions, including antivirus, anti-malware, EDR, vulnerability scanning and patch management
• Knowledgeable about security best practices, including operating system hardening, privileged access management and vulnerability mitigation
• Understand common threat tactics, techniques and procedures (TTPs) and effective countermeasures
• Well-versed in Windows core infrastructure services (AD/EntraID, PKI)
• Eager to produce scalable and repeatable security practices through automation
• Understand security tooling and APIs
• Flexible, reliable and highly collaborative
• Proven experience automating workflows in PowerShell or other scripting languages
• Fluent in English