Senior Mechanical Engineer

Senior Mechanical Engineer – Advanced Cooling

London (Hammersmith) | 3+ days per week in lab |

In most mechanical engineering jobs, you work within systems that others have already designed. Here, you will build the system yourself and set the standard for future engineers who join the team.

My client is a deep-tech startup developing advanced cooling hardware for AI data centres. As chips move toward direct-to-die cooling and 3D designs, heat flux is pushing traditional methods to their limits. The challenge is now mechanical as well as thermal. They are building new hardware to solve this, and they need a mechanical engineer to take full ownership of the problem from the start.

This is a hands‑on, hardware‑focused role. You will design and run test rigs for high‑heat‑flux, high‑pressure cooling systems, manage engineering documentation and safety standards, and work closely with the founding team on real technical challenges. You will also help define the company's approach to mechanical engineering.

The team is small currently. So, it requires someone who is comfortable growing in this scaling operation.

• Hands‑on experience designing, maintaining and running pressure systems (up to ~20 bar)
• A strong portfolio of delivered hardware — test rigs, prototypes, pressure‑containing assemblies
• Professional engineering documentation: logs, H&S procedures, technical reports
• FEA experience: contact, thermal, non-linear
• Safety instinct around hazardous systems is built in, not bolted on
• Comfortable working in early‑stage ambiguity without a fully defined spec

• Equity via EMI option pool
• Direct ownership of the mechanical engineering function with a clear path to building a team
• Working directly with two experienced deep tech founders at a genuinely pivotal moment

This role requires a minimum of three days per week in the Hammersmith lab. Right to work in the UK is required.

Interested? Click apply or get in touch to find out more.