Senior Rotation Engineer
Location: Delft, Netherlands.
Work model: Full-time, on site.
At Spiral Hydrogen you have a chance to do something extraordinary: shape the future of energy.
We started with a big question: what does civilization need to flourish? The answer we came to is: cheap green energy.
We are starting with hydrogen. Our novel electrolyzer design, which achieves 95% electrical efficiency (HHV) and eliminates many costly components, can deliver green hydrogen below gray hydrogen costs.
We just need you to make it happen.
So far, we have validated the core design, protected the IP, and got VC funding. Now we are preparing for a 100 kW pilot.
We are now looking for a mechanical engineer to own the mechanical design and hands-on build of the rotating electrolyzer stack.
What you'll do
This is a founding role. From the first 100 kW system onward, you'll help shape the technology's evolution as the team grows.
In practice, you will
Own the mechanical design and physical build of the rotating electrolyzers stack from beginning to the end.
Build and maintain full 3D CAD assemblies.
Obsess over sealing, leakage, tolerances, wobble, fatigue, and assembly.
Design and build test rigs and fixtures that measure performance reliably.
Select and validate materials for durability and compatibility.
Be open to continuous learning in a dynamic environment.
Iterate fast: build → test → break → improve.
Help define BOMs and work with suppliers to get parts made.
Spen real time in the workshop and lab.
You’ll often work on problems where nobody knows the right answer yet.
What we’re looking for
Strong candidates usually have:
Experience (5+ years) with rotating equipment or demanding machinery such as pumps, compressors, blowers, motors, bearings, seals, shafting, engines, test rigs, or turbomachinery.
Significant hands-on experience building real mechanical hardware.
Strong intuition for vibration, leak-tightness, fits and tolerances, wear, assembly, and reliability.
Comfort moving quickly between design, build, test, diagnosis, and iteration.
Experience in startups, R&D environments, labs, workshops, or industrial equipment teams.
The discipline to work carefully in the details without losing sight of the full system.
Clear communication.
These are strong pluses, not strict requirements:
Hands-on experience with alkaline electrolyzers or adjacent electrochemical/process equipment.
Experience spanning both small experimental devices and larger industrial hardware.
Fluid dynamics / CFD intuition.
Familiarity with corrosive environments, materials compatibility, and mechanical failure modes.
Comfort with basic electrical and instrumentation work.
Practicalities
Location: On-site in Delft, Netherlands (office + workshop at YES!Delft)
Time commitment: Full-time
Team: Small, technical, founder-led
Compensation: Competitive salary + equity for early employees
Start: As soon as possible
If this sounds exciting, let’s talk!
Note: Due to a large number of applicants we may not be able to respond to everyone. If you haven’t heard back from us in three weeks, please assume we have moved forward with other candidates. Thank you for your interest!