Penetration Tester

G-Research; City Of London; On-site; GBP 70,000 - 110,000; Full time

Benefits offered by this job

Competitive compensation

35 days annual leave

Healthcare and life assurance

Pension contributions 9%

Job summary

G-Research is seeking a Penetration Tester to lead and conduct security assessments across internal systems. You will deliver actionable remediation insights and collaborate on remediation strategies, strengthening our security posture.

The role emphasizes testing variety, automation, and mentoring, with a focus on Kubernetes/Jenkins/Windows domains and strong communication with stakeholders.

Qualifications

• Proven expertise across the full penetration testing lifecycle, from scoping to reporting and debriefs.
• Deep understanding of vulnerability assessment with remediation strategies for infra and apps.
• Strong background in security roles across diverse environments; familiar with DevOps technologies.

Responsibilities

• Performing in-depth penetration testing across various technologies and platforms.
• Delivering remediation advice to Control Owners based on identified vulnerabilities.
• Supporting owners in assessing and improving security controls and telemetry.

Skills

Penetration testing

Vulnerability assessment

DevSecOps

Automation tooling

Python scripting

Jenkins

Ansible

Communication

Education

OSCP

CRT

OSEP

Tools

Jenkins

Ansible

Python

Job description

We tackle the most complex problems in quantitative finance, by bringing scientific clarity to financial complexity.

From our London HQ, we unite world-class researchers and engineers in an environment that values deep exploration and methodical execution - because the best ideas take time to evolve. Together we're building a world-class platform to amplify our teams' most powerful ideas.

Security is foundational to this mission and must be delivered in a way that supports how our engineering teams build and operate complex systems at scale.

Take the next step in your career.

The role

As a Penetration Tester, you will lead and conduct penetration tests and vulnerability assessments across a wide range of internal systems and security controls. Your work will directly strengthen our overall security posture through continuous testing, actionable insights and collaboration on remediation strategies.

Key responsibilities of the role include:

• Performing in-depth penetration testing across a variety of technologies, including Kubernetes, Jenkins and Windows Domain Services
• Delivering practical, impactful remediation advice to Control Owners based on identified vulnerabilities
• Supporting business and application owners in assessing and improving the effectiveness of their security controls
• Providing technical consulting and assurance to Risk, Compliance and Detection Engineering teams, including control assessments and configuration reviews
• Maintaining and enhancing the team's operational tooling, automation and system integrations
• Mentoring and supporting less experienced team members, fostering knowledge sharing and growth

Who are we looking for?

The ideal candidate will have the following skills and experience:

• Proven expertise across the full penetration testing lifecycle, from scoping and execution to reporting and stakeholder debriefs
• Deep understanding of vulnerability assessment practices, including effective remediation strategies for both infrastructure and application-level security
• Strong background in technical security roles across diverse environments; familiarity with DevOps technologies
• Experience validating the effectiveness of security controls through both manual and automated approaches
• Engineering experience, particularly in building automation and tooling to streamline team output
• Proficiency in development and scripting tools commonly used in DevSecOps, including Python, Jenkins and Ansible.
• Relevant security certifications with OSCP required and CRT or OSEP desirable
• Strong communication and interpersonal skills, with an emphasis on clear and concise written output

Why join us?

• Highly competitive compensation plus annual discretionary bonus
• Lunch provided via Just Eat for Business and dedicated barista bar
• 35 days' annual leave
• 9% company pension contributions
• Informal dress code and excellent work-life balance
• Comprehensive healthcare and life assurance
• Cycle-to-work scheme
• Monthly company events

G-Research is committed to cultivating and preserving an inclusive work environment. We are an ideas-driven business and we place great value on diversity of experience and opinions.

We want to ensure that applicants receive a recruitment experience that enables them to perform at their best. If you have a disability or special need that requires accommodation please let us know in the relevant section