Penetration Tester

Barlowe LLP; Greater London; On-site; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Discretionary bonus

Lunch via Just Eat for Business

35 days annual leave

9% company pension contributions

Informal dress code

Comprehensive healthcare and life assu

Cycle-to-work scheme

Monthly company events

Job summary

G-Research is seeking a hands-on Penetration Tester to lead tests and vulnerability assessments across internal systems and security controls. Your work will strengthen our security posture through continuous testing and remediation collaboration.

You will perform tests across Kubernetes, Jenkins and Windows Domain Services, deliver remediation guidance, mentor teammates, and help build automation and tooling with Python, Ansible and related DevSecOps practices.

Qualifications

• Experience across the full penetration testing lifecycle, including scoping, execution, reporting and stakeholder debriefs.
• Strong vulnerability assessment practices with effective remediation strategies for infrastructure and application security.
• Background in technical security roles across diverse environments; familiarity with DevOps technologies.
• Experience validating security control effectiveness through manual and automated approaches.
• Engineering experience in building automation and tooling to streamline team output.
• Proficiency with development and scripting tools used in DevSecOps, including Python, Jenkins and Ansible.

Responsibilities

• Perform in-depth penetration testing across a variety of technologies, including Kubernetes, Jenkins and Windows Domain Services.
• Deliver practical, remediation guidance to Control Owners based on identified vulnerabilities.
• Support business and application owners in assessing and improving security controls effectiveness.
• Provide technical consulting to Risk, Compliance and Detection Engineering teams, including control assessments and configuration reviews.
• Maintain and enhance the team’s tooling, automation and system integrations.
• Mentor and support less experienced team members, fostering knowledge sharing and growth.

Skills

Penetration testing

Vulnerability assessment

DevOps familiarity

Python

Jenkins

Ansible

Communication

Education

OSCP

CRT or OSEP desirable

Tools

Kubernetes

Windows Domain Services

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.

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.

Responsibilities

• Perform in-depth penetration testing across a variety of technologies, including Kubernetes, Jenkins and Windows Domain Services.
• Deliver practical, impactful remediation advice to Control Owners based on identified vulnerabilities.
• Support business and application owners in assessing and improving the effectiveness of their security controls.
• Provide technical consulting and assurance to Risk, Compliance and Detection Engineering teams, including control assessments and configuration reviews.
• Maintain and enhance the team’s operational tooling, automation and system integrations.
• Mentor and support less experienced team members, fostering knowledge sharing and growth.

Qualifications

• 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 mandatory and CRT or OSEP desirable.
• Strong communication and interpersonal skills, with an emphasis on clear and concise written output.

Benefits

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

We are committed to cultivating and preserving an inclusive work environment. We value diversity of experience and opinions, and we want to ensure 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.

G‑Research is passionate about the intersection of finance, technology, and the future. We offer a dynamic, flexible and highly stimulating culture where worlds‑beating ideas are cultivated and rewarded, and we are proud to employ the best in their field and nurture talent in our collaborative working environment.