Algorithmic Software Developer – Space Surveillance & Tracking

The Space Defence and Intelligence business unit in CGI is a true IT Systems Integrator. We work build and operate bespoke technically complex mission-critical systems which help our clients keep us all safe and secure. We bring innovation to our clients using proven and emerging technologies agile delivery processes and our deep expertise across the breadth of space defence intelligence aerospace and maritime all underpinned by our end-to-end cyber capability. We work collaboratively with global technology companies cutting edge SMEs and academia to deliver the optimal solution for each client.

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.

CGI is on the lookout for a Senior Algorithmic Software Developer to help shape high-value solutions spanning surveillance track and flight dynamics and turn complex data and emerging techniques into trusted software that delivers meaningful outcomes. You will lead development across both exploratory and mature projects collaborate with experienced technical specialists and help grow a team through knowledge sharing and technical guidance. With the freedom to take ownership challenge ideas and explore new approaches alongside a supportive community of experts you will have the opportunity to make a lasting contribution to CGIs work in the space domain.

Due to the secure nature of the programme you will need to be a sole UK National and hold UK Security Clearance or be eligible to go through this clearance. This is a hybrid position based out of our office in Leatherhead with occasional travel requirements to customers in the UK Europe and potentially worldwide.

CGIs Secure Space Systems team is advancing how organisations understand monitor and respond to activity in this role you will take ownership of algorithmic software development for surveillance and tracking applications contributing across small projects and larger programme streams. You will lead a small team of developers providing direction technical guidance and quality review while working closely with senior technical leads to agree approaches respond to changing priorities and deliver agreed outcomes. You will combine applied mathematics software engineering and analytical thinking to develop robust trustworthy solutions.

You will also help turn research and new ideas into practical capability by investigating emerging techniques documenting findings and communicating results to internal and external stakeholders. You will have scope to challenge existing approaches improve development practices and contribute to business development activities supported by a collaborative environment that values initiative creativity and continuous learning.

Key responsibilities
Lead & Develop: Guide a small development team through direction mentoring quality review and best-practice delivery.
Design & Deliver: Develop and improve software algorithms for space surveillance and tracking.
Innovate & Investigate: Explore techniques in orbit determination flight dynamics tracking and correlation and machine learning.
Optimise & Validate: Define robust strategies for building confidence in software performance numerical accuracy and quality.
Collaborate & Influence: Work with technical leadership and internal and external stakeholders to agree approaches and communicate progress.
Report & Communicate: Produce clear internal and external reports technical papers and findings.
Contribute & Grow: Support business development activities and help broaden the teams technical capability.

Essential skills:

Applied mathematics: Strong competence applying mathematical concepts to software or algorithm development.
Algorithm development: Proven experience developing algorithms with consideration for numerical accuracy.
Software libraries: Experience with OREKIT Stone Soup or Keras.
Programming: Experience with Java or Python with willingness to develop broader capability.

Desirable skills:

STEM qualification: University degree or equivalent qualification in a relevant STEM discipline is highly desirable.
Leadership: Experience providing technical direction guidance or quality review to other developers.
Communication: Strong written and verbal interpersonal skills with confidence engaging stakeholders.
Ownership: Demonstrable willingness to take responsibility make decisions and deliver against agreed objectives.
Quality mindset: Commitment to best practice software quality and attention to detail.
Delivery methods: Understanding of software development lifecycles including Agile and/or Waterfall.
Space experience: Experience in the space sector or a closely related technical domain is desirable.
Additional technologies: Experience with C FORTRAN Julia and/or Git.

#LI-FP1

• C
• Java
• Python
• Software Design
• Software Design Patterns

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.

That same commitment to fairness extends to how we use technology. To support our recruitment team AI tools may be used to help assess applications though they never replace human judgement. All hiring decisions remain entirely in the hands of our recruitment professionals.

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