Principal Mechanical Engineer

cfsenergy· Tool Development
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📍 Milpitas, CAFull time💰 USD 150K–225K

About this role

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 Principal Mechanical Engineer   We’re looking for a Principal Mechanical Engineer to join our R&D and equipment design team to help build the next generation of thin-film deposition technology. You will be responsible for the end-to-end design, integration, and implementation of advanced thermal vacuum deposition systems and complex R&D machinery. This role requires you to be a technical expert who can drive innovative architecture while maintaining the procedural discipline necessary for high-performance hardware. If you enjoy solving complex thermal-mechanical problems in vacuum environments and mentoring others in a collaborative, fast-paced setting, this is your opportunity to make an impact.

Frequently Asked Questions

What is the salary for the Principal Mechanical Engineer role at cfsenergy?
The listed salary for this Principal Mechanical Engineer position at cfsenergy is USD 150K–225K. This is an Full time role.
Where is the Principal Mechanical Engineer position at cfsenergy located?
This Principal Mechanical Engineer role at cfsenergy is based in Milpitas, CA. The position is listed as on-site or hybrid. Check the full job description or apply directly to confirm the work arrangement.
Is the Principal Mechanical Engineer role at cfsenergy full-time or part-time?
This is listed as a Full time position. It is posted as a Principal Mechanical Engineer role in the Tool Development department at cfsenergy.
Which team or department does the Principal Mechanical Engineer at cfsenergy belong to?
This Principal Mechanical Engineer position is part of the Tool Development department at cfsenergy. See the full job description for more information about the team structure and responsibilities.
How do I apply for the Principal Mechanical Engineer position at cfsenergy?
Click the "Apply Now" button on this page. You will be redirected to cfsenergy's official application portal hosted on lever where you can submit your application directly.
When was the Principal Mechanical Engineer job at cfsenergy posted?
This Principal Mechanical Engineer position at cfsenergy was posted on Apr 15, 2026. Apply as soon as possible — early applications are often reviewed first.
Principal Mechanical Engineer
cfsenergy · 💰 USD 150K–225K
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