Senior Simulation Software Engineer

K2 is building the largest and highest-power satellites ever flown, unlocking performance levels previously out of reach across every orbit. Backed by $450M from leading investors including Altimeter Capital, Redpoint Ventures, T. Rowe Price, Lightspeed Venture Partners, Alpine Space Ventures, and others – with an additional $500M in signed contracts across commercial and US government customers – we’re mass-producing the highest-power satellite platforms ever built for missions from LEO to deep space. The rise of heavy-lift launch vehicles is shifting the industry from an era of mass constraint to one of mass abundance, and we believe this new era demands a fundamentally different class of spacecraft. Engineered to survive the harshest radiation environments and to fully capitalize on today’s and tomorrow’s massive rockets, K2 satellites deliver unmatched capability at constellation scale and across multiple orbits. With multiple launches planned through 2026 and 2027, we're Building Bigger to develop the solar system and become a Kardashev Type II (K2) civilization. If you are a motivated individual who thrives in a fast-paced environment and you're excited about contributing to the success of a groundbreaking Series C space startup, we’d love for you to apply. The Role You will be responsible for simulating and verifying the software used to fly some of the largest satellites that have ever been flown, using both hardware-in-the-loop and hardware-out-of-the-loop testing. Where needed, you will be able to step into different parts of the software stack to drive solutions end-to-end and even make changes to vehicle flight software. In your first 6 months you will develop core pieces of simulation software models, including adding new fidelity, fault injection capabilities, interfacing with simulation hardware, and modeling power systems. In your first year you will generalize simulation software architecture to allow testing and designing multiple spacecraft, demonstrating robust performance in demanding missions. In your first two years you will design many-agent simulations and design tools for operating entire constellations of satellites, informing critical company decisions. This role requires in person presence at our headquarters in Torrance, CA. Responsibilities Create and maintain simulation software infrastructure for our 20kW+ spacecraft Develop physics-based software models for testing control of spacecraft subsystems, including propulsion, guidance/attitude control, thermal, power, and communications systems Author drivers for simulation hardware Create and utilize robust tools to allow for rapid deployment of quality code Perform data analysis and anomaly investigation to identify and resolve software bugs Support integration and testing of spacecraft subsystems Qualifications Bachelor's degree in physics, aerospace/mechanical/electrical engineering, computer science, math, or a STEM field or 3+ years of professional experience in software engineering or relevant professions Development experience in Rust, C++, or similar compiled language Coursework or experience in numerical methods, ordinary differential equations, mechanics, and electricity and magnetism Nice to Have Master’s or PhD in physics, aerospace/mechanical/electrical engineering, or a STEM field Experience working in Rust production environments Experience using scientific Python (NumPy, SciPy, etc.), Julia, MATLAB, or similar Experience defining and creating simulation systems for both hardware-in-the-loop and hardware-out-of-the-loop testing Experience with Monte Carlo simulations and probability/statistics Experience with linear algebra, signal processing, controls, and/or orbital mechanics Experience with space communication modeling (RF, ground stations) Experience with continuous integration and continuous delivery systems Experience with spacecraft flight software development Experience with Linux systems ... (truncated, view full listing at source)