Salary: £70,000 - 75,000 per year Requirements: A degree in engineering, mathematics, or a science-based subject, or equivalent experience. Significant experience in embedded product development, including bare-metal and RTOS environments such as Linux or ThreadX. Expertise in C and C++, with a strong grasp of object-oriented design and design patterns. Familiarity with software testing, defensive coding standards, version control, and automated testing tools. Experience working in highly regulated environments and handling sensitive information. Eligibility for UK security clearance. A proactive approach to problem-solving and a commitment to delivering high-quality solutions. Responsibilities: Architect, design, develop, and test embedded and application software, ensuring high-quality and timely deliverables. Apply object-oriented design techniques to enable efficient code re-use and integration with testing frameworks. Review system design artefacts to derive software requirements and architecture aligned with high-level system objectives. Develop and maintain knowledge of best practices in software development, including TDD, BDD, DevSecOps, and secure coding standards. Mentor junior engineers, provide technical leadership, and contribute to the improvement of tools, processes, and techniques. Generate technical proposals and accurate estimates for bids and projects, ensuring cost and schedule adherence. Lead projects across the full software lifecycle from requirements and design through implementation, testing, and deployment. Contribute to multiple concurrent projects of varying scale and complexity. Support bids, cost estimation, and technical reviews. Technologies: Architect DevSecOps Embedded Support Linux Security TDD C++ More: We are offering a Principal Software Engineer role in Maidenhead, working full-time onsite on advanced cyber and defence programmes. This is a senior engineering position where you will help deliver innovative cryptographic and key management solutions for secure communication worldwide. You will work in a dynamic, collaborative environment with excellent benefits including private medical cover, flexible working hours, and participation in an annual bonus scheme. We are seeking someone who can combine hands-on development with technical leadership and strategic input to help us shape the future of defence systems. last updated 24 week of 2026