Senior Software Developer - 5G Core

At Capgemini Engineering​
The world leader in engineering services, we bring together a global team of engineers, scientists, and architects to help the world’s most innovative companies unleash their potential. From autonomous cars to life-saving robots, our digital and software technology experts think outside the box as they provide unique R&D and engineering services across all industries. Join us for a career full of opportunities. Where you can make a difference. Where no two days are the same.​
About the job you’re considering​
Senior Software Developer - 5G Core (Stevenage/HYBRID)
A brilliant opportunity to advance your career while working with cutting-edge technologies in the 5G Core network domain as a Senior Software Developer with expertise in microservices.
Hybrid working: The places that you work from day to day will vary according to your role, your needs, and those of the business; it will be a blend of Company offices, client sites, and your home; noting that you will be unable to work at home 100% of the time.​
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If you are successfully offered this position, you will go through a series of pre-employment checks, including: ​identity, nationality (single or dual) or immigration status, employment history going back 3 continuous years, and unspent criminal record check (known as Disclosure and Barring Service)​
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Your role

• Design and Implement SBA Services: Develop microservice-based components such as AMF, SMF, PCF, NRF, and others in alignment with 3GPP standards (e.g., TS 23.501, 29.500).
  
• RESTful API Development: Build and manage REST APIs for inter-NF (Network Function) communication. Ensure API compliance with OpenAPI specs and 3GPP-defined message flows.
  
• Cloud-Native Deployment: Use container technologies like Docker and Kubernetes to deploy services in scalable, resilient environments-whether on public cloud (AWS, Azure) or private 5G telco clouds.
  
• Performance and Reliability: Ensure high performance, scalability, and reliability of network services. Optimize services for low latency and high throughput.
  
• CI/CD and DevOps: Integrate code into automated pipelines for continuous integration and deployment. Collaborate with DevOps teams to ensure smooth service rollouts and updates.
  
• Testing and Debugging: Write unit, integration, and system-level tests. Debug real-time issues in simulated or live test environments.
  
• Documentation and Standards Compliance: Keep thorough documentation of designs, APIs, and implementations. Maintain compliance with evolving 3GPP standards.
  You can bring your whole self to work. At Capgemini building an inclusive future is part of everyday life and will be part of your working reality. We have built a representative and welcoming environment, for everyone.​
  Your skills and experience​
  Bachelor's or Master's degree in Computer Science, Telecommunications, or related field.
  
• 7+ years of experience in telecom software development, ideally in 4G/5G Core domains.
  
• OS Proficiency - Linux (Ubuntu/Debian)
  
• Good Understanding of Networking Concepts IP, UDP, TCP, SCTP
  
• Hands-on experience with 5G SBA network functions (e.g., AMF, SMF, NRF, PCF, UDM).
  
• Strong programming skills in languages such as Go, Java, or C++.
  
• Proficient in building microservices and working with REST/gRPC APIs.
  
• Solid understanding of 3GPP specs (especially TS 23.501, 23.502, 29.500+ series).
  
• Experience with Docker, Kubernetes, Helm, and cloud platforms (AWS, Azure, or OpenShift).
  
• Familiarity with network protocols (HTTP/2, SCTP, Diameter, PFCP).
  
• CI/CD tools and test automation experience (Jenkins, GitLab, Robot Framework, etc.).
  Don’t meet every single requirements? Studies have shown women and people of colour are less likely to apply to jobs unless they meet every single qualification. We are dedicated to building a diverse, inclusive and authentic workplace so if you’re excited about this role but your past experience doesn’t align perfectly with every requirement in the job description, we encourage you to apply anyway.​
  Your security clearance
  To be successfully appointed to this role you will need to undergo Baseline Personnel Security Standard checks. ​
  There are no nationality or residency restrictions, although if you have resided outside of the UK within the last 3 years, further checks may be required.​
  There are other criteria and checks required for BPSS, and throughout the recruitment process, you will be asked questions about your security clearance eligibility such as, but not limited to, country of residence and nationality.
  What does ‘Get The Future You Want ‘ mean for you?​
  You’d be joining an accredited Great Place to work for Wellbeing in 2024. Employee wellbeing is vitally important to us as an organisation. We see a healthy and happy workforce a critical component for us to achieve our organisational ambitions. ​
  To help support wellbeing we have trained ‘Mental Health Champions’ across each of our business areas, and we have invested in wellbeing apps such as Thrive and Peppy.
  You will be empowered to explore, innovate, and progress. You will benefit from Capgemini’s ‘learning for life’ mindset, meaning you will have countless training and development opportunities from thinktanks to hackathons, and access to 250,000 courses with numerous external certifications from AWS, Microsoft, Harvard ManageMentor, Cybersecurity qualifications and much more.
  Why you should consider Capgemini​
  Growing clients’ businesses while building a more sustainable, more inclusive future is a tough ask. When you join Capgemini, you’ll join a thriving company and become part of a collective of free-thinkers, entrepreneurs and industry experts. We find new ways technology can help us reimagine what’s possible. It’s why, together, we seek out opportunities that will transform the world’s leading businesses, and it’s how you’ll gain the experiences and connections you need to shape your future. By learning from each other every day, sharing knowledge, and always pushing yourself to do better, you’ll build the skills you want. You’ll use your skills to help our clients leverage technology to innovate and grow their business. So, it might not always be easy, but making the world a better place rarely is.​
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  About Capgemini
  Capgemini is a global business and technology transformation partner, helping organisations to accelerate their dual transition to a digital and sustainable world, while creating tangible impact for enterprises and society. It is a responsible and diverse group of 340,000 team members in more than 50 countries. With its strong over 55-year heritage, Capgemini is trusted by its clients to unlock the value of technology to address the entire breadth of their business needs. It delivers end-to-end services and solutions leveraging strengths from strategy and design to engineering, all fuelled by its market leading capabilities in AI, generative AI, cloud and data, combined with its deep industry expertise and partner ecosystem. The Group reported 2024 global revenues of €22.1 billion