freehire launches on Product Hunt on 26 August.

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Principal Software Engineer

Summary

Principal Software Engineer building embedded systems using C/C++ and RTOS like Linux/ThreadX, with a focus on bare-metal development and testing.

Salary: £70,000 - 75,000 per year

Requirements:
  • We require a degree in engineering, mathematics, or a science-based subject, or equivalent experience.
  • We require significant experience in embedded product development, including bare-metal systems and RTOSes such as Linux or ThreadX.
  • We require expertise in C and C++, with a strong grasp of object-oriented design and design patterns.
  • We require familiarity with software testing, defensive coding standards, version control, and automated testing tools.
  • We require a proactive approach to problem-solving and a commitment to delivering high-quality solutions.
  • Candidates must be eligible for UK security clearance.
  • We require experience working in highly regulated environments and handling sensitive information.
Responsibilities:
  • We architect, design, develop, and test embedded and application software, ensuring high-quality and timely deliverables.
  • We apply object-oriented design techniques to enable efficient code reuse and integration with testing frameworks.
  • We review system design artefacts to derive software requirements and architecture aligned with high-level system objectives.
  • We develop and maintain knowledge of best practices in software development, including TDD/BDD, DevSecOps, and secure coding standards.
  • We mentor junior engineers, provide technical leadership, and contribute to the improvement of tools, processes, and techniques.
  • We generate technical proposals and accurate estimates for bids and projects, ensuring cost and schedule adherence.
  • We lead the design, architecture, and delivery of secure embedded and application software across the full software lifecycle.
  • We support bids, cost estimation, and technical reviews.
  • We contribute to multiple concurrent projects with varying scales and complexity.
Technologies:
  • Architect
  • DevSecOps
  • Embedded
  • Support
  • Linux
  • Security
  • TDD
  • C++

More:

We are a defence technology company delivering innovative cryptographic and key management solutions that ensure secure communication for customers worldwide. This is a senior Principal Software Engineer role in a dynamic and collaborative environment, based full-time onsite in Maidenhead. We offer excellent benefits including private medical cover, flexible working hours, and participation in an annual bonus scheme. You will play a vital role in shaping advanced defence systems that protect lives and redefine security, combining hands-on development with technical leadership and strategic input.

last updated 32 week of 2026

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