Principal Software Engineer - Python / Simulation

Principal Software Engineer - Python / Simulation

A Frontier AI startup backed by $170m in funding is hiring a Staff Software Engineer to build the distributed backend systems powering next-generation modelling & simulation platforms for defence and autonomous systems. Their technology enables engineers to develop, validate and deploy AI-generated software inside high-fidelity virtual environments, allowing autonomous systems to be tested at scale before deployment into the real world. This is a rare chance to join at a pivotal stage of growth, working alongside a team that has already assembled some of the most credible technical talent in the industry. The team includes alumni from OpenAI, Google Research, Microsoft AI and NASA, combining deep foundation model research with world-class systems engineering and mathematical expertise.

This is a hands-on, deeply technical position focused on architecting the distributed backend infrastructure that underpins large-scale simulation workloads and autonomous AI agents. You'll be building high-performance Python services responsible for orchestrating complex simulation environments, managing distributed execution, processing vast volumes of simulation data, and ensuring the reliability and scalability of mission-critical systems. The simulations model real-world environments where autonomous software can be exercised against changing terrain, sensor inputs, communications constraints and adversarial conditions, allowing engineers to rapidly evaluate, iterate and validate new capabilities. You'll work closely with AI researchers, systems engineers and simulation specialists to ensure these environments can operate efficiently across large distributed compute clusters while supporting next-generation autonomous software development.

Experience Required:

• 7+ years' experience building backend systems with Python
• Strong experience designing distributed systems and scalable backend architectures
• Experience building platforms for large-scale compute, simulation, data processing or distributed workloads
• Experience with cloud infrastructure (AWS preferred)
• Background in defence, robotics, modelling & simulation, scientific computing or other performance-critical environments (highly desirable)
• Exposure to compilers, language tooling, formal methods or software verification (beneficial)
• Proven technical leadership and architectural ownership

This is an opportunity to build the backend infrastructure behind some of the most advanced modelling & simulation capabilities being developed today. Your work will enable AI-generated software to be tested, validated and refined across thousands of simulated scenarios before deployment, directly influencing the reliability of autonomous systems operating in complex, mission-critical environments. If you're excited by distributed systems, high-performance computing and simulation at scale—and want to work alongside some of the strongest engineers and researchers in AI—this is an exceptional opportunity.