CS GROUP, together with HE Space and Sopra Steria, has been successfully providing digital end-to-end systems and engineering services for more than 40 years. With over 2000 employees worldwide, we combine advanced and unique skills in both information technology and space data engineering. We combine entrepreneurial agility with cutting-edge technological expertise. CS GROUP is a leading provider of operational systems and an important and trusted long-term partner for space and defence organisations. At CS GROUP, we are driven by innovation and we value our most important asset: our people.

As part of the On-board Software and Functional Verification (FV) team, you will contribute to the development of software for the ESA Vigil satellite programme, supporting one of Europe's flagship space missions.

Working in a Continuous Deployment environment, you will be involved in the design, implementation, integration and verification of on-board software, collaborating closely with multidisciplinary engineering teams to ensure the successful delivery of high-quality software solutions.

Your responsibilities will include:

• Designing, developing and maintaining on-board software using C++;
• Developing and maintaining software models and simulation environments;
• Supporting hardware-in-the-loop (HIL) design, integration and testing activities;
• Debugging and troubleshooting real-time software in Linux environments;
• Contributing to Continuous Integration and Continuous Deployment (CI/CD) pipelines;
• Designing and implementing multi-process and multi-threaded software applications;
• Developing and executing software verification activities, including unit and integration testing;
• Applying software engineering best practices, object-oriented design principles and design patterns;
• Producing and maintaining technical documentation in accordance with ECSS standards;
• Working closely with systems, avionics and verification engineers throughout the software development lifecycle;
• Communicating technical concepts effectively to both technical and non-technical stakeholders.

You will have the following qualifications and relevant experience:

• University degree in Computer Science, Software Engineering, Aerospace Engineering or a related technical discipline;
• At least 4 years of industrial experience in software engineering (5+ years preferred);
• Strong software design and development experience using C++;
• Good working knowledge of Java (primarily for software testing activities);
• Experience designing and debugging real-time software in Linux (RedHat) environments;
• Experience with Hardware-in-the-Loop (HIL) systems;
• Experience working with Continuous Integration and Continuous Deployment (CI/CD) environments;
• Strong understanding of multi-process and multi-threaded software architectures;
• Experience with software testing methodologies and unit testing frameworks;
• Knowledge of Object-Oriented Analysis and Design (OOAD) using UML or similar modelling techniques;
• Good understanding of the complete Software Development Life Cycle (SDLC);
• Knowledge of software design patterns and modern coding best practices;
• Familiarity with software development frameworks, tools and utilities;
• Experience with machine-to-machine communication protocols;
• Excellent communication and presentation skills in English.

The following experience would be considered a strong advantage:

• Experience with spacecraft avionics systems;
• Knowledge of ECSS software standards, particularly ECSS PUS;
• Experience with SpaceWire, MIL-STD-1553 and CAN Bus communication protocols;
• Previous experience working on ESA or other space programmes.

This role is based in Stevenage, United Kingdom

The position requires full-time onsite presence (4 days per week onsite, 1 day remote).

If you believe you have what it takes for this position, please send your CV (in English and in Word or PDF format) to Andrés Izquierdo by clicking on the ‘Apply for this job’ button and quoting job reference.

An exciting and dynamic international working environment awaits you!

Last apply date: 31/08/2026!