Software Development Engineer in Test (SDET)

We’re creating the UK’s next-generation engineering powerhouse, delivering critical technology that strengthens national security and resilience.

We turn advances in sensing, AI and communications into operational capability at the edge, where connectivity may be limited or unavailable. Our work accelerates technology deployment, improves frontline decision-making, and protects people and critical assets in demanding environments.

Based in Bristol, Rowden currently employs around 200 people and operates more than 20,000 square feet of engineering and manufacturing facilities. With a growing international presence, we are one of Europe’s fastest-growing engineering businesses.

The role

We’re growing our team and looking for a Software Development Engineer in Test (SDET) to enable us to continue to build out our test frameworks, tooling and emulated environments that underpin assured software across complex, mission-critical systems.

You’ll take responsibility for software quality within your projects, playing a key part in ensuring Rowden’s software is robust, reliable, and meets the standards expected by our mission-focused customers.

This is an engineering role as much as a testing one. You’ll design and build new automation frameworks from the ground up, and develop our emulated test capability, such as network and link emulation, simulated devices and nodes, and stand-ins for cloud services, so that we can test distributed, data-synchronising systems repeatably and under realistic, degraded conditions without needing the full hardware estate.

You’ll work across a diverse set of projects, including bespoke mobile applications, geospatial tooling, cloud platforms, sensing and provisioning systems. Many of these integrate closely with hardware, so experience working across software and hardware ecosystems is essential.

You’ll operate confidently across multidisciplinary environments, contribute to complex deliveries and help shape how we approach quality in challenging, real-world conditions. You will play a pivotal role in delivering our next generation of critical technologies that bridge the gap between frontline operators and the commercial advancements they need to succeed.

While this role offers hybrid working options, it requires a minimum of 3 days per week on-site at our Bristol HQ, with occasional travel to support integration and testing activities.

Candidates must be eligible for SC clearance.

More information about security clearance is available here: https://www.gov.uk/government/publications/united-kingdom-security-vetting-clearance-levels

Key areas of responsibility

As a Software Development Engineer in Test, you will:

• Design and build test frameworks: Design, build and maintain test automation frameworks and shared tooling from the ground up, choosing appropriate architectures, languages and libraries, and treating test code as production-quality software.
• Develop emulated capability: Build and evolve emulated and simulated test environments (for example network and link conditions, devices, nodes and cloud services) to enable repeatable testing of distributed, data-synchronising systems under degraded or intermittent connectivity.
• Embed automation in delivery pipelines: Integrate automated tests into CI/CD, owning pipeline reliability, reporting and the management of flaky tests.
• Drive quality through best practice: Following and promoting consistent test standards, applying sound judgement and effective risk management.
• Coaching & Mentoring: Support and coach peers on automation practice and use of the frameworks you build.

Key skills, experience and behaviours

We are seeking passionate and driven individuals who thrive on technology and actively invest in their technical skills and abilities. Relevant and transferable industry experience is a bonus when applying for this role, but not essential. This role offers significant opportunities to grow and gain valuable experience and we’re looking for someone who already brings:

Essential

• 3+ years’ test automation or software development experience.
• Strong software development skills in at least one language used for test tooling (for example Python, TypeScript or Java), with sound engineering practice including version control, code review, modular design and testing your own test code.
• Proven experience designing and building test automation frameworks from scratch, not simply writing tests into existing frameworks.
• Use of modern tools and frameworks (e.g. Playwright, PyTest, UI Automator).
• Experience of Git and building, running and maintaining automated tests in CI/CD pipelines such as GitHub Actions.
• Experience in working with APIs and integration test automation.
• Solid understanding of networking and distributed-system fundamentals (for example latency, packet loss, partitions, offline-first behaviour, conflict resolution and eventual consistency) and how to test for them.
• Experience translating requirements and user stories into comprehensive test suites, including consideration of accessibility, usability and mobile best practices.

Desirable

• Experience building emulators, simulators, mocks or service virtualisation, or network and fault-injection tooling.
• Experience testing Android-based systems.
• Experience testing software with connected hardware and troubleshooting integration and interoperability issues.
• Experience setting up, running and maintaining CI runners, including physical runners (for example Raspberry Pi, NUCs).
• Networking experience (for example USB, serial, network switching) and scripting (e.g. Bash) for device control.
• Knowledge of security, performance, resilience, load and other non-functional testing areas.
• ISTQB or equivalent certifications.
• Understanding of how AI can be best-utilised across the software test lifecycle.
• Experience working within assurance-driven, safety-critical or highly regulated environments.

About you

The ideal candidate will have a thorough understanding of the software testing craft and be comfortable navigating their way through complex environments. You will:

• Work with a high degree of autonomy, taking responsibility for the quality of your own work and the design of the test solutions you build, and making sound, evidence-based decisions in fast-moving environments.
• Approach problems like an engineer, with a pragmatic, delivery-focused mindset that balances robust design with the need to move at pace.
• Work effectively across multidisciplinary teams, collaborating daily with fellow engineers, product, and operational stakeholders.
• Contribute to ways of working, supporting consistency and continuous improvement with a proactive approach to solving problems.
• Share knowledge and support the development of automation amongst peers.
• Operate confidently in customer-facing environments, supporting integration and test activities and facilitating discussions around quality.

Working at Rowden

We are committed to building a flexible, inclusive, and enabling company. Our aim is to create a diverse team of talented people with unique skills, experience, and backgrounds, so please apply and come as you are!

We also recognise the importance of flexible working and support this wherever we can. We typically operate a flexible, hybrid-working model, with an average 3 days in the office each week (dependent on the role). We welcome the opportunity to discuss flexibility, part-time working requirements and/or workplace adjustments with all our applicants.

Rowden is a Disability Confident Committed company, and we actively encourage people with disabilities and health conditions to apply for our roles. Please let us know your requirements early on so that we can make sure you have everything you need up front to help make the recruitment process and experience as easy as possible.

Finally, if you feel that you don’t meet all the criteria included above but have transferable skills and relevant experience, we’d still love to hear from you!