Location
Central London

Hours
Full Time

Salary
£53,267 to £62,599 per annum

About the Role
MI5 keeps the country safe from serious threats like terrorism and attempts by states to harm the UK, its people and way of life. We carry out investigations by obtaining, analysing, and assessing intelligence, and then work with a range of partners including MI6 and GCHQ to disrupt these threats. Through our protective security arm, we provide advice and guidance to government, businesses and other organisations about how to keep themselves safe. A role in MI5 means you'll do unique and challenging work in a supportive and encouraging environment, making a real difference to UK national security.

As a Lead Cyber Research Engineer, you’ll play a central role in identifying vulnerabilities, understanding how systems can be exploited and developing practical ways to defend them. Combining hands-on engineering with deep security expertise, you’ll help shape how cyber threats are understood, tested and mitigated across a complex and evolving technology landscape.

Working in a highly collaborative environment, you’ll tackle challenging security problems through a mix of research, experimentation and engineering. This could involve analysing attack techniques, reverse engineering software, testing systems under real-world conditions or building bespoke tools to uncover and demonstrate vulnerabilities. The work is varied and often fast-moving, requiring both technical depth and creative problem-solving.

You’ll contribute to the development of new security capabilities, working closely with engineers, researchers and stakeholders to ensure solutions are effective, scalable and usable. Writing code, building tooling and creating repeatable processes will form a core part of the role, helping to improve both efficiency and impact.

As a lead, you’ll provide technical direction within your team – guiding approaches, shaping solutions and supporting others to deliver high-quality work. Mentoring and knowledge sharing are central, helping to develop capability and promote strong engineering and security practices, without the requirement for formal line management.

Operating across teams, you’ll influence how security is approached more broadly – working with others to strengthen resilience, improve understanding of risk and ensure systems are robust against evolving threats.

Benefits
You’ll benefit from a well-established and flexible development programme designed to support both your technical depth and leadership capability. From the outset, you’ll receive a structured induction within your team, alongside wider familiarisation with the broader organisation and its technical landscape.

Ongoing development is a core part of the role. You’ll have access to a wide range of learning opportunities, from self-directed research and development days through to formal external training and industry-recognised certifications, aligned to your areas of interest and business need. This could include areas such as cloud technologies, networking, systems engineering or specialist security disciplines like reverse engineering and forensics.

You’ll also be supported to attend and contribute to internal and external conferences, sharing knowledge and staying connected to developments in the wider cyber security community.

Learning is embedded in the day-to-day – through hands-on problem solving, collaboration and mentoring others. You’ll continue to grow your own expertise while also helping develop those around you, strengthening capability across the team over time.

Additional benefits include 25 days annual leave automatically rising to 30 days after 5 years' service, plus 10.5 days public and privilege holidays, opportunities to be recognised through our employee performance scheme, a dedicated development budget, interest-free season ticket loan, excellent pension scheme, cycle to work scheme, facilities such as a gym, restaurant, and on-site coffee bars (at some locations), and paid parental and adoption leave.

Experience
Strong technical experience across cyber security and software or systems engineering, with the ability to understand how technologies work at a deep level and how they can be exploited. Experience may come from areas such as security research, reverse engineering, vulnerability discovery, systems programming or working with operating systems and networks.

Confident coding skills across a range of languages (for example Python, Java or C/C++), used to test, prototype or build tools. Practical experience investigating real-world problems, identifying vulnerabilities and developing effective solutions.

About you
Analytical thinker with curiosity and a research-driven approach to problem solving. Able to communicate findings clearly through written outputs, presentations or direct collaboration to explain risks and recommendations.

Enjoys working collaboratively, sharing knowledge and supporting others to develop. Comfortable guiding others, contributing to technical direction and helping raise standards across a team without formal leadership experience.

Qualifications
While no specific formal qualifications are stated, candidates must demonstrate developed knowledge of programming in high and low-level languages, experience in security research, reverse engineering, or operating system internals, and knowledge of networking and protocols. The role requires the highest security clearance (Developed Vetting) and British citizenship or dual British nationality.