About Commonwealth Fusion Systems: Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy. Combining decades of research, top talent, and new technologies, we’re designing and building commercially viable fusion power plants. And we're working with policymakers and suppliers to build the energy industry of the future. We’re in the best position to make it happen. Since 2018, we’ve raised nearly $3 billion in capital, making us the largest and leading private fusion company in the world. Now we’re looking for more thinkers, doers, builders, and makers to join us. People who’ll bring new perspectives, solve tough problems, and thrive as part of a team. If that’s you and this role fits, we want to hear from you. Join the power movement as a Staff Mechanical Engineer We’re looking for a Staff Mechanical Engineer to join our R&D and equipment design team to help build the next generation of thin-film deposition technology. Serving as the "Second Chair" within our engineering group, you will be a high-impact technical leader who leads by example, solving highly complex, semi-ambiguous problems that influence the success of multiple teams. You will be responsible for the end-to-end design, integration, and implementation of advanced thermal vacuum deposition systems and complex R&D machinery. Operating with near-complete independence, you will manage long-term assignments with loosely-defined outcomes, balancing expert-level technical execution with the operational discipline required to ship high-performance hardware.