Site Reliability Engineer, British Intelligence Agencies

MI5, Covert Capability

£44.2-53k

£44,190 to £52,972 depending on skills and accreditation. This role qualifies for a specialist capability-based pay approach, which recognises and rewards cyber technical expertise. Based on an assessment of skills and experience at interview, you may be eligible for an additional skills payment, potentially increasing the salary to £52,972. To retain the higher salary, you will need to demonstrate and accredit your skills against our Cyber Technical Framework within the first year of employment.

Kubernetes

Python

Mid level

London

More information about location

4-5 days a week in office

UK's domestic and foreign intelligence services

Posted today

UK's domestic and foreign intelligence services

1001+ employees

SecurityGovernmentsCyber Security

Posted today

£44.2-53k

Kubernetes

Python

Mid level

London

More information about location

4-5 days a week in office

1001+ employees

SecurityGovernmentsCyber Security

Company mission

MI5, MI6 and GCHQ work together to protect the UK from a range of national security and overseas threats, keeping citizens safe.

Job

Company

Role

Who you are

You’re an experienced engineer with a strong background in building, deploying and maintaining software or infrastructure in production environments. Your experience may come from site reliability engineering, DevOps or a similar role, and you’ll be used to working with complex systems where reliability, performance and security are critical
You bring hands-on experience managing systems through their full lifecycle, including deploying, upgrading and maintaining services in live environments without disruption. You’re confident working in code-driven environments, using approaches such as infrastructure as code and automation to deliver and manage infrastructure
You’ll have practical experience using Kubernetes to deploy and manage services in production environments. You’ll also have working knowledge of scripting or programming languages such as Python and be comfortable working in Linux-based environments
You understand how systems behave in production, using logs, metrics and monitoring tools to assess health, identify issues and improve performance. You take a structured and methodical approach to your work, ensuring systems are stable, repeatable and well managed
You’re able to understand complex systems and how different components interact and can communicate this clearly to others. You work effectively with engineers and supporting teams, ensuring systems are well documented and delivered to a consistent standard
To work at MI5, you need to be a British citizen or hold dual British nationality

What the job involves

As a Site Reliability Engineer, you’ll design, build, deploy and maintain the infrastructure that enables critical cyber activity. Working in a highly technical environment, you’ll ensure the systems others depend on are secure, reliable and fit for purpose. Using a blend of cutting-edge and bespoke technologies, including internally developed systems you won’t find elsewhere, you’ll solve complex, mission-critical challenges
This is an engineering-led role where you’ll play a key part in delivering and managing infrastructure through code, operating in fully code-driven environments. Using tools such as Kubernetes, infrastructure as code and automation frameworks, you’ll develop and manage production environments that support operational activity. You’ll oversee deployments end to end, manage upgrades and changes, and ensure systems remain stable and available without disruption, maintaining continuity of service
Monitoring is central to the role. You’ll track system health, performance and behaviour using logs and metrics, identifying risks and weaknesses before they impact service. When issues arise, you’ll investigate root causes and contribute to improvements that strengthen reliability and prevent recurrence
Day to day, you’ll work closely with engineers, developers and researchers to deploy new capabilities and improve existing systems. You’ll collaborate with monitoring teams to respond to system concerns and ensure environments remain secure and resilient. Alongside this, you’ll contribute to improving how systems are managed, refining processes and strengthening reliability practices as systems evolve
Operating within a small, specialist team in a wider delivery environment, you’ll have the autonomy to influence how production systems are managed and delivered. This is a hands-on engineering role focused on ensuring systems are robust, consistently available and capable of supporting critical operational activity

Application process

An initial online application form including pre-screening questions to ensure you meet our eligibility criteria
Online Situational Judgement Test (SJT) in which you rate the appropriateness of responses to a series of short scenarios
A full online application form, assessed at application sift, where we will review your motivation for the role and MI5
Online competency-based interview which will also consider your motivation for the role
In-person technical interview
If successful, you’ll receive a conditional offer of employment

Salary benchmarks

Our take

The British Intelligence Agencies - GCHQ, MI5 and MI6 play crucial roles in protecting the nation from a range of security threats. By focusing on counterterrorism, espionage, and cyber threats, the unified force works to safeguard the public and support law enforcement agencies. Its work, largely behind the scenes, is pivotal in ensuring national security.

With origins dating back to the 19th century, each of the British Intelligence Agencies plays a specific role within the security services. GCHQ focuses on signal intelligence gathering and information assurance, MI5 on counterterrorism and national security, whilst MI6 is focused on foreign intelligence and overseas security. This evolution into three specific organisations reflects the agency's ability to stay ahead of emerging security challenges, adjusting its strategy and operations as needed.

As technology and global threats change, the British Intelligence Agencies' approaches continue to evolve, ensuring the UK's security remains a top priority. With its deep expertise and ongoing adaptation, they are major key players in protecting national and international interests, whilst responding to complex security dynamics.

Kirsty

Company Specialist at Welcome to the Jungle

Company

Company benefits

Merit awards – we have a merit award system to recognise exceptional contributions by individuals or team
Flexible working – opportunities to work part-time, compressed hours or as a job share are available, dependent on the role and business needs
Pension – we understand the importance of saving for retirement and offer a desirable pension scheme, which gives you a guaranteed pension based on career average earnings
Annual leave – our employees are entitled to 25 days annual leave, rising to 30 days after five years’ service. In addition to this, employees are entitled to public and privilege holidays. Part-time employees receive the same entitlement calculated on a pro-rata basis
Maternity and paternity leave – we offer maternity and paternity leave over and above the statutory entitlements
Voluntary service leave – we offer special leave for our employees who wish to undertake voluntary work
Rented accommodation loan – moving house to take up an offer of employment can be expensive. We offer new joiners the opportunity to take out an interest-free loan of up to £2,500, via our benevolent fund, to assist with the financial burden of relocating into privately rented accommodation. You will be sent an application for the loan at the point of receiving a final offer of employment
Season ticket loan – we recognise that travel expenses from your home to the office can be significant, so we offer an interest-free season ticket loan which can be used for travel, car park costs or the purchase of a bicycle
On-site facilities – there is a gym, restaurant, and coffee bar at some locations
Clubs and societies – we offer a range of sports clubs, fitness classes, societies, and language training facilities
Childcare Vouchers – we offer two childcare voucher schemes which provide a simple and cost-effective way for employees to receive help towards the cost of childcare
Eye Voucher Scheme – we offer eye care vouchers and a financial contribution towards prescription glasses
Physiotherapy – we offer subsidised in-house physiotherapy
Personal learning – all our staff can undertake professional development to improve their skills and performance in the workplace

Company HQ

Manchester, UK

Articles

GCHQ chief opens £5.8m cyber and digital centre

MI5: Official Secrets Exhibition Shortlisted For National Award

Speech by Blaise Metreweli, Chief of MI6, 15 December 2025

Leadership

Ken McCallum

(Director General)

An MI5 Officer with over 25 years of experience in national security and intelligence. Their career has spanned roles in counterterrorism, cyber security, and leading MI5's strategic response to major incidents. They were appointed Director General in 2020 and previously served as Deputy Director General and Director General of Strategy.

Blaise Metreweli

(Chief)

Blaise joined the Service in 1999 and has had a range of roles, most recently Director General Technology & Innovation (Q). She has spent most of her career operationally in the Middle East & Europe.

Anne Keast-Butler

(Director)

Became the first female Director of GCHQ in May 2023. Previously served as Deputy Director General at MI5, where they led operational and investigative work, including responding to the Russian invasion of Ukraine. With over 30 years in national security, they have held key roles in MI5, GCHQ, and Whitehall, including launching the National Security Programme.

Diversity, Equity & Inclusion at British Intelligence Agencies

At the Intelligence Agencies, 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. Find out more about our culture, working environment, and diversity on our website: https://www.gchq-careers.co.uk/life-at-gchq/diversity-inclusion.html

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