Principal Security Engineer in London

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. At our scale and complexity, security challenges are rarely isolated or superficial. They span systems, teams, and time, and require deep technical judgement to address effectively.

The role of Principal Security Engineer exists to address cross‑cutting challenges, providing deep technical leadership across the firm and helping to shape how security is designed, assessed and evolved at G‑Research. Reporting directly to the Head of Security, you will tackle complex, ambiguous and high‑impact security problems, often in areas where clear ownership does not already exist. Rather than own a single product, domain or team, you will operate as a firm‑wide technical authority, leading problem definition, design and delivery of solutions that raise the organisation’s overall security capability.

You will work closely with senior engineers, security specialists and technology leaders, influencing decisions through evidence, technical judgement and collaboration within G‑Research’s consensus‑driven and academically rigorous culture.

Key responsibilities of the role include:

• System‑level security leadership
• Identifying, framing and driving resolution of complex security problems spanning teams, systems and organisational boundaries
• Defining clear technical approaches where requirements, constraints or ownership are not yet established
• Ensuring security is addressed coherently across infrastructure, platforms, applications and operational processes
• Applying deep security expertise to the design and evolution of systems across the firm, particularly around identity, access control, software delivery, infrastructure and systemic risk
• Contributing directly to technical work through design, prototyping, review and targeted implementation
• Setting a high bar for technical quality, robustness and long‑term maintainability
• Working closely with senior engineers, engineering managers and security leaders to align on technical direction and priorities
• Acting as a technical peer to senior stakeholders across engineering, security operations, risk and audit
• Influencing decisions through reasoned argument, evidence and collaboration in environments with strong technical viewpoints
• Helping teams navigate trade‑offs between security, performance, reliability and delivery
• Acting as a technical reference point and mentor for senior security engineers across the organisation
• Shaping security engineering standards, patterns and ways of working that scale across G‑Research
• Supporting the development of future technical leaders through modelling effective judgement and collaboration
• Maintaining a firm‑wide view of security risk and identifying systemic weaknesses
• Supporting security and technology leadership in understanding complex technical risks and making informed decisions

Who are we looking for?

We are looking for an exceptional security engineer with the depth, judgement, and credibility to operate as a principal‑level individual contributor in a highly technical environment. The ideal candidate will have the following skills and experience:

• Extensive experience solving complex security problems in large‑scale, production systems
• Deep technical expertise across multiple areas of security engineering, such as application security, infrastructure security, identity and access management, secure software delivery or incident response.
• A strong track record of influencing technical direction across teams without direct authority
• Excellent engineering fundamentals and the ability to engage meaningfully with complex systems and codebases
• Proven effectiveness in environments where decisions are shaped through technical discussion, debate and consensus
• Clear, precise communication skills, with the ability to explain complex security topics to both deeply technical and senior stakeholders

This role is suited to engineers who prefer solving the hardest problems, raising the technical bar for others, and shaping systems over time, rather than owning a single roadmap or team.

Why join us?

• Highly competitive compensation plus annual discretionary bonus
• Lunch provided (via Just Eat for Business) and dedicated barista bar
• 30 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