Software Engineer (C++)

Position Description:

At CGI were redefining whats possible in the Space Defence and Intelligence sector delivering secure mission-critical systems that protect the UK and drive national capability. As a C Software Engineer youll help design and implement next-generation solutions that enable operational excellence and resilience in the most demanding environments. Youll be part of a trusted team that values innovation ownership and collaborationempowering you to shape the future of defence technology while advancing your own career through continuous learning and professional growth.

CGI was recognised in the Sunday Times Best Places to Work List 2025 and has been named a UK Best Employer by the Financial Times. We offer a competitive salary excellent pension private healthcare plus a share scheme (3.5% 3.5% matching) which makes you a CGI Partner not just an employee. We are committed to inclusivity building a genuinely diverse community of tech talent and inspiring everyone to pursue careers in our sector including our Armed Forces and are proud to hold a Gold Award in recognition of our support of the Armed Forces Corporate Covenant. Join us and youll be part of an open friendly community of experts. Well train and support you in taking your career wherever you want it to go.

Due to the highly secure nature of the work this role is only open to sole UK Nationals who hold or are eligible to hold High-Level Clearance (HLC). While hybrid or remote working may be possible regular attendance at the secure site will be required.

Your future duties and responsibilities:

In this role you will engineer high-performance secure software systems that underpin mission-critical defence operations. Youll collaborate with clients and cross-functional teams to design develop and deliver robust solutions that meet exacting standards of performance and reliability. Your expertise will directly influence the success of strategic projects ensuring our clients maintain a technological edge in national security.

Youll take ownership of your work from concept through delivery bringing creativity and precision to every challenge. Supported by CGIs collaborative culture youll have opportunities to innovate contribute to technical direction and build a rewarding purpose-driven career.

Key responsibilities:

Design & Develop: Create and maintain high-quality modern C software solutions aligned with mission objectives.

Collaborate & Innovate: Work closely with multidisciplinary teams and clients to translate technical requirements into effective solutions.

Optimise & Secure: Apply secure coding standards performance optimisation and rigorous testing practices.

Deliver & Evolve: Contribute to Agile ceremonies CI/CD pipelines and continuous improvement initiatives.

Document & Communicate: Produce clear technical documentation and contribute to knowledge-sharing across teams.

Required qualifications to be successful in this role:

You should have strong experience developing secure high-performance software using modern C and be passionate about delivering reliable systems that make a real difference. A background in defence aerospace or similar high-assurance environments is advantageous but not essential.

Essential qualifications:

Proven experience with modern C (C11 and above) and OOD principles.

Solid understanding of multithreading concurrency and real-time software design.

Familiarity with Linux and cross-platform development environments.

Experience with CI/CD tools version control and unit testing frameworks.

Awareness of secure coding standards and best practices.

Strong analytical and problem-solving skills with the ability to work effectively in collaborative teams.

Desirable qualifications:

Experience in embedded or mission-critical systems.

Knowledge of middleware technologies (e.g. DDS ZeroMQ) and scripting (Python Bash).

Understanding of Agile delivery models such as Scrum or SAFe.

#LI-JS2

Skills:

• English
• Java
• RESTful (Rest-APIs)

What you can expect from us:

Together as owners lets turn meaningful insights into action.

Life at CGI is rooted in ownership teamwork respect and belonging. Here youll reach your full potential because

You are invited to be an owner from day 1 as we work together to bring our Dream to life. Thats why we call ourselves CGI Partners rather than employees. We benefit from our collective success and actively shape our companys strategy and direction.

Your work creates value. Youll develop innovative solutions and build relationships with teammates and clients while accessing global capabilities to scale your ideas embrace new opportunities and benefit from expansive industry and technology expertise.

Youll shape your career by joining a company built to grow and last. Youll be supported by leaders who care about your health and well-being and provide you with opportunities to deepen your skills and broaden your horizons.

Come join our teamone of the largest IT and business consulting services firms in the world.