Python Developers in London

CGI’s Space, Defence and Intelligence business unit focuses on delivering contemporary and innovative technical solutions to government agencies tackling some of the most complex challenges. We design, build, and operate bespoke, mission-critical systems that help keep the UK safe and secure.

We are looking for experienced Python Developers to join our cross-functional teams. Working closely with our clients, you will help design, build, and deliver secure, scalable solutions in a highly rewarding and impactful environment. CGI places strong emphasis on learning and development, ensuring your skills evolve alongside the latest technologies. Our culture promotes innovation, collaboration, and ownership—ideal for motivated self-starters.

Due to the secure nature of the work, these roles require UK Security Clearance and sole UK nationality. Candidates should either already hold DV clearance or be willing and eligible to obtain it.

Your future duties and responsibilities:

As a Python Developer, you will contribute to the delivery of cloud-based, data-intensive systems. Your responsibilities will include:

• Designing, developing, and maintaining robust Python applications
• Building scalable APIs and backend services
• Working with large datasets and data processing pipelines
• Contributing to system architecture and technical design decisions
• Automating workflows and improving deployment pipelines
• Maintaining and enhancing cloud-based environments (primarily AWS)
• Supporting live systems and implementing enhancements when required
• Collaborating with cross-functional teams in agile environments

We’re looking for individuals with a strong problem-solving mindset who can adapt quickly to evolving client needs.

Required qualifications to be successful in this role:

We are particularly interested in candidates with strong Python development experience, alongside exposure to some of the following:

• Core Skills:
• Python (primary language)
• Experience with frameworks such as FastAPI, Flask, or Django
• Strong understanding of RESTful APIs and microservices architecture
• Cloud & DevOps:
• AWS (e.g. Lambda, EC2, S3, RDS)
• CI/CD tools such as Jenkins or GitLab CI/CD
• Infrastructure as Code (e.g. Terraform)
• Data & Integration:
• Working with large datasets and data pipelines
• Tools such as Apache NiFi or similar integration frameworks
• Scripting & Automation:
• Bash, Ansible
• Monitoring & Logging:
• ELK Stack (Elasticsearch, Logstash, Kibana), Grafana
• Testing & Quality:
• Automated testing frameworks (e.g. PyTest, Cucumber)
• Code quality tools such as SonarQube

Experience across multiple areas is beneficial, but not essential. A willingness to learn and contribute across the stack is key. Candidates must hold, or be eligible to obtain, Developed Vetting (DV) clearance.

What you can expect from us:

Together, as owners, let’s turn meaningful insights into action. Life at CGI is rooted in ownership, teamwork, respect and belonging. Here, you’ll 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. That’s why we call ourselves CGI Partners rather than employees. We benefit from our collective success and actively shape our company’s strategy and direction.

Your work creates value. You’ll 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.

You’ll shape your career by joining a company built to grow and last. You’ll 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 team—one of the largest IT and business consulting services firms in the world.