Full job descriptionSenior Software Test Engineer (Python & Embedded Systems)
Salary: Up to £75,000 per annum, depending on experience
Location: Predominantly remote, with occasional visits to Farnborough
Security Requirements: Sole UK National | Eligible for SC Clearance, with the ability to progress to DV Clearance
Are you looking for a better work-life balance without leaving the defence sector behind?
If you have experience on defence or national security programmes and want greater flexibility with less time spent on-site, this could be the opportunity you’re looking for.
We’re seeking a Senior Software Test Engineer with a strong background in embedded software and firmware testing to help ensure the quality, reliability and performance of complex device-based systems. This is a senior, hands-on position where you’ll shape test strategy while remaining involved in automation, integration testing and fault investigation.
You’ll work on challenging non-deterministic systems, designing robust test approaches where software behaviour can vary based on system state, environmental conditions and external inputs. You’ll also take ownership of Python-based automation frameworks, driving quality standards and continuous improvement across the engineering team.
This is an excellent opportunity to join a highly skilled team, solve complex technical challenges and influence the testing approach for cutting-edge embedded systems within a secure defence environment.
What You’ll Be Doing
*Lead the testing strategy for complex embedded software and firmware products.
*Design, develop and maintain Python-based automated test frameworks.
*Create robust test approaches for non-deterministic systems, validating behaviour where outputs may vary based on environmental conditions, system state or external inputs.
*Design test cases for complex and uncertain scenarios, ensuring system resilience under real-world operating conditions.
*Perform software, firmware, integration and system-level testing across hardware and software environments.
*Analyse intermittent, non-repeatable and unexpected behaviours to identify root causes.
*Collaborate closely with Embedded Software Engineers throughout the software development lifecycle.
*Support firmware releases, deployments, upgrades and regression testing activities.
*Drive continuous improvement across testing processes, tooling and automation capability.
*Mentor engineers and promote best practice in software quality and test design.
*Contribute to CI/CD pipelines and quality gates for software delivery.
Essential Skills & Experience
*Significant experience testing embedded software systems and firmware.
*Strong understanding of the embedded software development lifecycle.
*Experience working on defence, aerospace, government, national security or other highly regulated engineering programmes.
*Understanding of hardware/software integration challenges and system-level testing.
*Experience testing products that interact with physical devices, sensors, communications equipment or embedded platforms.
*Extensive experience designing and executing test strategies for complex software systems.
*Strong background in test design, exploratory testing and risk-based testing techniques.
*Experience testing non-deterministic systems, artificial intelligence-enabled systems, autonomous platforms or software where outcomes are not always predictable.
*Ability to analyse ambiguous test results and develop meaningful validation approaches.
*Experience of manual, automated, integration, system and regression testing.
*Strong Python development skills with proven experience building and maintaining automated test frameworks.
*Experience integrating automated testing into CI/CD environments.
*Knowledge of modern test automation tools and methodologies.
*Experience creating reusable, scalable and maintainable automation solutions.
*Knowledge of firmware deployment, upgrades and version management.
*Experience working with Linux-based environments.
*Understanding of software quality metrics, defect management and release processes.
*Strong troubleshooting and root-cause analysis skills.
Security Requirements
Due to the nature of the work, applicants must:
*Be a sole UK national.
*Be eligible and willing to obtain Security Check (SC) Clearance.
*Be capable of obtaining Developed Vetting (DV) Clearance in the future if required.
*Have the unrestricted right to work in the UK without needing sponsorship.
Benefits
*Salary up to £75,000 depending on experience.
*Performance-related bonus.
*Private healthcare.
*Enhanced pension contribution.
*Ongoing professional development and training.
*Predominantly remote working.


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