Senior Firmware Engineer

You’ll join a multidisciplinary team of engineers and scientists working on our core automation platform, from first prototypes through to production systems. You’ll design, implement and test firmware that runs on ARM microcontrollers, work directly with hardware on the bench, and help shape technical decisions across firmware, electronics and the wider system.

This is not a role confined to the firmware team: you may spend as much time working with electronics, mechanical, automation and systems engineers, and with biologists, as you do with other firmware or software engineers. You’ll need to enjoy crossing disciplinary boundaries and learning enough about the wider system to help make it work as one coherent whole.

In this role, you’ll:

• Own firmware development for key parts of our core technology, from requirements and architecture through implementation, verification and support in production.
• Write and review high-quality C for ARM microcontrollers (primarily STM32), focusing on robust, maintainable and testable code.
• Design and maintain automated tests for embedded firmware, including unit, integration and hardware-in-the-loop, and integrate them into continuous integration workflows.
• Turn system needs into clear firmware requirements and interfaces, working directly with electronics, mechanical, automation and software engineers, plus biologists.
• Make and communicate technical decisions within your area, balancing engineering rigour, maintainability and delivery speed, and support other engineers through design discussions and code reviews.
• Debug complex embedded-system issues using tools such as debug probes, oscilloscopes, multimeters and logic analysers, getting to the root cause of tricky problems.
• Use Linux-based tools and development environments as part of your day-to-day work.
• Support and occasionally develop custom test equipment for internal use, helping the wider team move faster.
• Use higher-level languages such as Python, C# or Java to build supporting tools and simple GUIs for debugging, testing or internal users.

Depending on your experience, you may also:

• Turn your hand to electronics design and prototype modification when needed, working with electronics engineers to shape interfaces and resolve cross-discipline issues.
• Develop and optimise hard real-time algorithms for motion control, sensing or safety-critical functions.
• Use Docker and containers to create reliable, repeatable development and test environments.
• Contribute to embedded Linux software and the interfaces between it and our microcontroller firmware.

About you

You enjoy seeing firmware come to life in real hardware, and you like being close to the bench, motors and sensors rather than hidden away from the physical system. You are comfortable owning firmware end to end, from first requirements and architecture through to code that ships, and you get energy from solving problems with people from different technical backgrounds.

We’re looking for:

• A strong track record of designing and delivering embedded systems, with the judgement to take ownership and make pragmatic technical decisions independently.
• Extensive professional experience developing firmware in C and/or C++ on ARM microcontrollers, ideally STM32.
• Strong experience developing and maintaining automated tests for embedded systems, including using them within continuous integration workflows.
• Confidence working directly with hardware and independently debugging complex systems at both code and signal level.
• Strong skills in interpreting component datasheets and electronics schematics, and using them to inform design and debugging.
• A collaborative, entrepreneurial approach, with the ability to explain technical trade-offs, support other engineers and solve problems with people from very different disciplines.

Cellular Origins is currently based on the TTP Campus, within purpose-built sustainable offices, labs and green surroundings, 10 miles south of Cambridge. Our working culture encourages entrepreneurship, shared ideas and collaboration, while providing you the freedom to do your best work.

Our employee benefits include:

• Annual bonus
• 25 days holiday
• Employer pension contribution of 10% of salary
• Private medical insurance for employees and dependants
• Enhanced family friendly leave
• Life insurance worth 6x salary
• Electric car leasing scheme
• Cycle to work scheme
• Season ticket loan