Expleo is a trusted partner for end-to-end, integrated engineering, quality services and management consulting for digital transformation.  We help businesses harness unrelenting technological change to successfully deliver innovations that will help them gain a competitive advantage and improve the everyday lives of people around the globe.

We are looking for a highly capable, multi-disciplined engineer to support the end-to-end development, secure configuration, integration, and operation of secure computing products for our client in the Defence sector.

This role combines C# software engineering, secure operating system development, hardware handling, systems integration, and security-by-design practices. The engineer will work within a high-assurance, MOD-accredited environment involving products certified up to Top Secret baseline.

Software Engineering (C# Focus)

• Develop new C# software based on an existing Java codebase.
• Translate and implement Java functionality into C#.
• Provide limited Java support during the transition period.
• Build middleware components, integration layers, and secure software modules.
• Ensure all code conforms to secure-by-design and accreditation-driven standards.

Secure Operating System Engineering

• Support secure OS build and configuration activities for:
• Windows 11 secure laptop OS builds
• Windows Server 2025 virtualised/containerised platform
• Containerised Linux-2 environments (future integration)
• Assist with secure image creation, application deployment, lockdown configuration, and privilege control.
• Follow government-accredited OS hardening and secure configuration guidelines.

Hardware Engineering Activities

• Build and wire engineering rigs for test and integration.
• Dismantle and modify laptops for secure hardware changes, including:
• Internal battery removal
• Storage and memory replacement
• Basic FPGA module handling
• Adhere to Thales hardware security and handling procedures.

Networking & Systems Integration

• Support secure network configuration and integration activities.
• Cable and integrate server kits, power amplifiers, logic controllers, and other connected components.
• Assist with system-level integration between environments.

• Degree (or equivalent experience) in Software Engineering, Computer Science, Cybersecurity, Electronics, or a related discipline.
• Industry experience in secure systems, defence, national security, or high-assurance environments is advantageous.

• Strong C# development experience, with the ability to work from and interpret existing Java logic.
• Solid understanding of secure-by-design engineering practices.
• Experience with Windows internals, secure OS image creation, or secure deployment processes.
• Basic hardware engineering competency (laptop tear-down, component replacement, cabling).
• Networking fundamentals applicable to secure system integration.
• Experience with virtualisation and/or container technologies.
• Proven problem-solving ability and a proactive, full-lifecycle engineering mindset.
• Ability to operate effectively in MOD-accredited, high-assurance environments.

• Experience with government-accredited secure configuration standards (e.g., NCSC, MOD JSP).
• Familiarity with secure laptop builds, privileged access controls, or FIPS-accredited hardware.
• Exposure to FPGA modules, hardware security modules, or custom hardware integration.
• Knowledge of Windows Server 2025, Linux containerisation, or mixed-OS environments.
• Experience in middleware development or system-level software integration.

• SC Cleared (mandatory)
• Sole UK National
• Applicants must be legally able to work in the UK and meet security requirements for restricted environments

• Collaborative working environment – we stand shoulder to shoulder with our clients and our peers through good times and challenges  
• We empower all passionate technology loving professionals by allowing them to expand their skills and take part in inspiring projects   
• Expleo Academy - enables you to acquire and develop the right skills by delivering a suite of accredited training courses  
• Competitive company benefits
• Always working as one team, our people are not afraid to think big and challenge the status quo 

• As a Disability Confident Committed Employer we have committed to:

• Ensure our recruitment process is inclusive and accessible
• Communicating and promoting vacancies
• Offering an interview to disabled people who meet the minimum criteria for the job
• Anticipating and providing reasonable adjustments as required
• Supporting any existing employee who acquires a disability or long term health condition, enabling them to stay in work at least one activity that will make a difference for disabled people

“We are an equal opportunities employer and welcome applications from all suitably qualified persons regardless of their race, sex, disability, religion/belief, sexual orientation or age”. 

We treat everyone fairly and equitably across the organisation, including providing any additional support and adjustments needed for everyone to thrive