Senior Cyber Security Engineer in Harwell

At Open Cosmos we are solving the world’s biggest challenges from space, providing businesses, governments and researchers access to more readily available information than ever before. Working in our Chief Operating Office (COO), our COO Teams are the engine that powers Open Cosmos’ operations. This division brings together mission management, supply chain, and quality & product assurance to make sure every mission is delivered smoothly, reliably, and to the highest standards.

We are looking for a Senior Cyber Security Engineer, who’ll play a critical role in protecting the systems that power our satellites, ground operations, and global infrastructure.

What will you be doing?

• This is a hands-on role focused on strengthening our security posture end-to-end.
• You’ll work across cloud, corporate, and mission-critical environments, embedding security into how we build, operate, and scale.
• Strengthening the security posture of our cloud environments (AWS, Azure, GCP) through continuous improvement and optimisation.
• Implementing and evolving Zero Trust principles across identity, access, and system design.
• Securing satellite ground segment and operational infrastructure, ensuring clear separation from corporate environments.
• Continuously hardening systems across endpoints, networks, and cloud platforms.
• Designing and improving detection capabilities across SIEM and XDR tools, moving beyond standard alerts.
• Developing detection logic to identify anomalous behaviour across infrastructure, applications, and telemetry.
• Leading technical responses to security incidents, including investigation, containment, and root cause analysis.
• Building and refining incident response playbooks to ensure consistent and effective handling of threats.
• Managing vulnerabilities end-to-end, from identification through to validated remediation.
• Embedding security into development workflows by integrating tooling into CI/CD pipelines.
• Partnering with engineering teams to ensure systems and applications are secure by design.
• Automating security processes to improve response times and reduce manual effort.
• Continuously improving security tooling, processes, and controls across the organisation.

What You’ll bring

• Strong understanding of cyber security across infrastructure, cloud environments, and applications.
• Deep knowledge of public cloud security (GCP, AWS, Azure) and SaaS platforms such as Microsoft 365.
• Familiarity with SIEM/XDR platforms and vulnerability management tools.
• Solid understanding of identity and access management, Zero Trust architectures, and secure network design.
• Ability to write scripts or code to automate security tasks (e.g. Python, Bash, PowerShell).
• Strong knowledge of Linux and Windows systems, including system hardening approaches.
• Understanding of secure software development practices and how to integrate security into CI/CD pipelines.
• A proactive mindset, taking ownership of security challenges and driving improvements.
• Curiosity to explore new threats, tools, and approaches in a constantly evolving landscape.
• Ability to collaborate effectively across technical teams and embed security into everyday work.
• A pragmatic approach, balancing strong security with operational needs.
• Clear communication of technical risks and solutions to a range of stakeholders.

For this role you can be based in any of our locations.