About the job

The Senior Developer (Physics Simulation & Optimisation) role at ToffeeX in London offers an exciting opportunity to work at the intersection of mathematics, engineering, and technology within a rapidly growing company. The successful candidate will develop and implement advanced mathematical models that power the ToffeeX engineering design platform, tackling challenging real-world problems in physics simulation, optimisation, and computational geometry. Responsibilities include designing and implementing novel algorithms for multi-physics simulation and PDE-constrained optimisation, collaborating with engineers and developers to integrate new capabilities into cloud-based design software, contributing across the full software development lifecycle, and working with customer success teams to tailor solutions to user needs. Candidates should have a Ph.D. in Applied Mathematics, Physics, Engineering, or a related field, along with research-level experience in areas such as physics-based simulation (FVM/FEM), PDE-constrained optimisation, mathematical optimisation, AI/ML techniques for simulation, mathematical modelling, and computational geometry, plus hands-on experience with numerical algorithms. Desirable experience includes leading projects or teams, proficiency in C++ and Python, and familiarity with CFD tools like OpenFOAM or SU2. The company offers benefits such as professional growth support, 25 days holiday plus bank holidays, private healthcare, pension scheme, cycle to work scheme, employee discounts, work-from-home Fridays, team socials, and visa sponsorship. ToffeeX is revolutionising engineering design with AI-driven simulation and optimisation tools delivered via a cloud-based platform, and has recently been recognised in the Startups.co.uk 100 Index 2025.