Platform Engineer Ref. 3781 in London

Salary: £66,332, with an opportunity to qualify for additional allowances and a skills‑related payment under the Government Digital and Data Capability Framework (GDDPCF), formally the (DDaT) Digital, Data and Technology Capability Framework.

We offer a range of flexible working options to support a healthy work‑life balance, including part‑time arrangements and compressed hours, and flexibility around start and finish times through flexitime. This role is office‑based and does not offer home working.

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 on 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 Platform Engineer, you'll design, develop and operate platforms that give developers the tools they need to build critical technology that helps keep the country safe. Joining MI5 offers the opportunity to contribute to a growing technology capability while being part of an expanding engineering workforce, helping to enhance platforms and products delivered across the organisation.

Day to day, the role involves building developer tooling, managed services, and automation, along with self‑service solutions. Infrastructure‑as‑code is used to ensure consistency and reliability across cloud and on‑premises environments, enabling teams to move quickly with confidence.

A significant part of the role centres on working closely with our product teams, understanding pain points, prioritising what matters most, and shaping solutions that meaningfully improve the developer experience. The outcome is streamlined workflows, reduced friction, and more time for engineers to focus on delivering solutions to meet MI5’s outcomes. You’ll play a key part in contributing to our engineering community by sharing best practice standards, patterns, and establishing clear and consistent approaches that teams can adopt with confidence.

When issues arise, you’ll get stuck in, troubleshooting platform problems and improving reliability, usability, and observability, while feeding those insights back into better design. Sharing knowledge across teams will be a big part of the role, as will helping to build a consistent, collaborative engineering culture. You’ll also support other engineers, helping them build confidence and develop their skills.

We know that platform engineering evolves constantly, and the quality of this role depends on keeping pace with it. As a result, there is a regular protected time to horizon scan, research emerging trends, and pursue training or certifications relevant to your career.

A natural problem solver, you enjoy tackling complex challenges and turning them into practical solutions. Experience may come from working as a Platform or DevOps Engineer across a range of technologies and customer environments, or from a Software Engineering background with demonstrable experience in solving platform and infrastructure‑related challenges in current or recent roles.

An understanding of the software development lifecycle in an enterprise or commercial environment is essential, alongside familiarity with design patterns and secure coding practices.

Working closely with engineers and technologists, this role focuses on understanding challenges and shaping effective platform solutions. Confidence communicating with both technical and non‑technical audiences is important, particularly when explaining ideas clearly, aligning on priorities, and building trust across teams.

You’ll be comfortable working independently with a high level of autonomy, making pragmatic decisions and seeing work through from problem to solution. Being proactive in seeking support from senior engineers and leaders when needed, along with a willingness to learn and grow, is also important.

Proficiency in at least one modern programming language, such as Node.js, Python, or Java, is expected along with experience in core engineering practices including TDD, CI/CD pipelines, cloud services, and agile methodologies. Familiarity with infrastructure‑as‑code tools such as Terraform is also important.

We’re committed to developing our engineers, with a clear career structure designed to enable progression and continuous growth. From day one, you’ll be encouraged and supported to shape your development in ways that reflect personal strengths and interests.

A dedicated development budget and personal development days are provided, alongside access to a wide range of courses, online platforms, qualifications, and certifications to support your development, covering both technical and soft skills. There are also opportunities to benefit from coaching and mentoring within or outside of your team.

Learning is both individual and collective. Up to 20% of working time is available for innovation and personal development, creating a space to explore new ideas, deepen technical expertise, and stay close to emerging technologies.

Building on this, there’s a comprehensive training and development pathway on offer, which uses the Government Digital and Data Profession Capability Framework (GDDPCF). It includes tailored training, coaching and mentoring, alongside opportunities to gain qualifications and pursue specialist Agile Delivery pathways, if this interests you.

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

At MI5, diversity and inclusion are critical to our mission. To protect the UK, we need a truly diverse workforce that reflects the society we serve. This includes diversity in every sense of the word: those with different backgrounds, ages, ethnicities, gender identities, sexual orientations, ways of thinking and those with disabilities or neurodivergent conditions. We therefore welcome and encourage applications from everyone, including those from groups that are underrepresented in our workforce such as women, those from ethnic minority backgrounds, people with disabilities, and those from low socio‑economic backgrounds.

MI5 is proud to have achieved Leader status within the Department for Work and Pension’s Disability Confident scheme. This is aimed at encouraging employers to think differently about disability and take action to improve how they recruit, retain and develop disabled people. As a Disability Confident Leader, we aim to ensure that a fair and proportionate number of disabled applicants who best meet the essential minimum criteria for this position, will be offered an interview, if it is practical for us to do so.

To secure an interview for this role, the minimum criteria are:

• You’ll be required to reach the minimum pass mark for the online Situational Judgement Test (SJT), which assesses criteria important for all roles in our organisation.
• Demonstrate the ability to develop software in at least one common language (assessed at application form sift).
• Demonstrate an understanding of the principles of modern standards approaches such as continuous integration and delivery, test driven development and cloud services (assessed at application form sift).
• Demonstrate the ability to provide technical direction and guide and support others with regards to software developing (assessed at application form sift).

There is a wide range of extra support available throughout the recruitment process to enable you to do your best.