Principal Mechanical Engineer

ABOUT THE ROLE Join a small defense technology team developing autonomous directed-energy systems for counter-drone applications. As Principal Mechanical Engineer, you will guide full-system mechanical architecture and integration, bringing hardware from prototype through production and field deployment. WHAT YOU'LL DO - Own mechanical architecture across the system and lead integration with electrical, power, embedded, and optical subsystems. - Make and guide technical decisions from concept through production readiness. - Drive hardware release and production processes in partnership with manufacturing. - Review designs, calculations, and test results to surface risks and strengthen engineering standards. - Perform hands-on design and problem-solving, including tradeoffs across cost, mass, reliability, schedule, and field performance. - Mentor engineers through technical collaboration and example. WHAT WE'RE LOOKING FOR - 10 or more years designing and shipping complex hardware systems, with repeated experience taking products from prototype through manufacturing and field deployment. - Mechanical design is your primary discipline, including hands-on CAD, structures, mechanisms, and packaging. - Deep mechanical expertise and sound technical judgment in at least one adjacent area, such as electrical engineering, power electronics, or embedded systems. - Experience leading multidisciplinary hardware integration and designing equipment for demanding real-world environments. - Ability to correlate your own FEA or hand calculations with bench or field test data. - Background as a senior individual contributor or technical lead at a hardware company that shipped products. - Defense, aerospace, robotics, high-performance automotive, maritime, or directed-energy experience is relevant. Experience with ruggedized systems, thermal management, gimbals, qualification standards, or manufacturing setup is valuable. COMPENSATION & BENEFITS Base salary: $235,000 to $305,000 annually. Visa sponsorship is not available. LOCATION On-site in San Francisco, California.