Neutronics Engineer

WHO WE ARE Proxima Fusion is Europe’s fastest-growing fusion company and the continent’s best-funded fusion player, as well as the first spin-out from the Max Planck Institute for Plasma Physics (IPP). Backed by over €650M and powered by a growing team across Munich, Zurich, and Oxford, we are developing the hardware and infrastructure needed to deliver the world’s first commercial stellarator fusion power plant.   Our concept advances the most mature fusion technology out there, the Wendelstein 7-X stellarator, through two next-generation machines: Alpha and Stellaris. Our work combines stellarator optimization, advanced computation, machine learning, and high-temperature superconducting magnets to unlock higher-performance designs that were previously out of reach. Turning these designs into a functioning fusion power plant requires excellence and ownership across every discipline, from physics and engineering to software, manufacturing, law, and business functions.   BY JOINING OUR TEAM YOU’LL GET TO - Shape the architecture of the world’s first commercial fusion power plant – Own system-level decisions that determine how a first-of-a-kind energy technology is designed, integrated, and ultimately deployed at scale. - Solve some of the most complex engineering challenges – Work across tightly coupled disciplines (plasma physics, magnets, cryogenics, manufacturing, controls, and more) to resolve critical trade-offs and turn cutting-edge science into a functioning product. - Design real hardware with a pragmatic, fast-moving team from all over the world – Combine advanced simulation and systems thinking with a strong execution mindset, focusing on practical engineering solutions that accelerate the path to commercial fusion energy. YOUR IMPACT As a member of the neutronics group you will play a critical role in advancing our stellarator design. Your work will focus on analysis required for licensing and operational safety of the Alpha stellarator. You will carry out reproducible neutronics simulations and automate neutronics simulation workflows. Simulations include producing shutdown dose rate maps, unstructured mesh magnet heating, tritium breeding, DPA, activation, using both CSG and CAD-based neutronics models. The role provides a unique opportunity to work as part of an integrated design effort including machine learning experts, software engineers, fusion scientists, and fusion engineers, making a tangible impact on the future of clean energy. WHAT YOU WILL DO - Perform neutronics analysis using OpenMC and DAGMC for a range of neutron and photon responses important for stellarator optimization and design. - Contribute to the integration of neutronics analysis into automated pipelines, including programming in Python (essential skill), using version control (Git/Graphite) within a Docker environment, Programming in C++ is considered a benefit. - Perform verification and validation by comparing simulation results obtained with OpenMC to other codes and experimental data. - Construct simulation ready CAD with CadQuery and CSG geometries of the stellarator and surrounding facility. - In addition to developing in-house neutronics workflows, you may have opportunities to contribute to open-source codes we depend on for nuclear data processing, CAD conversion / meshing, and particle transport simulations. WHO YOU ARE - A PhD or Master’s degree in nuclear physics, nuclear engineering, or equivalent experience. - Experience in processing nuclear data. - Experience with the main codes that we use (OpenMC, DAGMC, CadQuery, Gmsh) for neutronics analysis. - Experience designing neutron and gamma shielding. - Experienced Python programmer using software development tools such as Git - Experience with computation in cloud or HPC environments involving numerical simulations (desirable). INTERVIEW PROCESS - Recruiter Interview (30-60 min) - Technical Screening (30 min) - Technical Panel (3x60 min) - CEO call (30 min) This role sits at L2/L3 of our framework, please inquire during the recruitment process for further information* At Proxima Fusion, our mission is bold: making limitless clean energy a reality. To get there, we need a high-performing, diverse team that brings different perspectives, challenges assumptions, and builds together with purpose. We know that diversity of thought and experience leads to better ideas, stronger execution, and a more resilient team. We don’t look at how you identify, what you look like, who you choose to worship or what ethnicity you are. We care about what you can bring to the table.