Role
Commonwealth Fusion Systems is hiring a Staff Fuel Cycle & Blanket Test Engineer to lead testing, operation and maintenance of laboratory systems for fusion fuel cycle and molten salt technology. The engineer supports the Tritium and Blanket program with integrated tests, new lab capabilities and capital plant projects that mature tritium-handling and blanket technology toward the company's first power plant.
Responsibilities: Develop commissioning and test plans for tritium or blanket test stands and lead major test campaigns from start-up into routine operation. Build the physical and documentation infrastructure needed to scale research and production work. Operate and maintain gas-handling and molten salt systems, contribute to hazardous-material facility commissioning, author and peer-review procedures and reports, and help build training programs.
Requirements: An MS in engineering (such as chemical, materials, micro-nano, or mechanical with a heat- and mass-transport focus), physics, chemistry or a related field, with 10 years of experience. Candidates need experience building and executing R&D testing, working with technicians and senior scientists in a laboratory, rigorous data management with programmatic reporting, Python data analysis, and clear lab reports and presentations. Safety-minded test execution and independent problem solving are expected.
Preferred experience: More than 10 years in a production or laboratory setting; high-purity, rare or tritium gases; molten salts or corrosive fluids; glovebox work and protective equipment for hazardous materials; analytical equipment and high-vacuum systems; Confluence and JIRA; and process plant documentation.
Working arrangements: The role involves occasional lifting up to 50 lbs, extended typing, standing or sitting, and occasional travel to suppliers and to commissioning or test activities. Industrial hazards include strong magnets, high voltage, pressure systems and cryogenics. Any offer depends on compliance with U.S. export-control laws.
Snapshot
| Employer | Commonwealth Fusion Systems |
| Workplace | Devens, Massachusetts, US |
| Onsite | Onsite |
| Employment type | Full-time |
| Salary | $130,000–$200,000 a year |
| Date posted | 2026-09-30 |
| Expires | — |
| Verified | 2026-10-06 |
Sources & verification
The original publication date is exactly as posted on the employer ATS — no substitutions. The links below are the same ATS pages we used to verify this listing; the dates come from when we last checked them.
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