Senior Mechanical Engineer - Vacuum Systems
Pacific Fusion· Renewables & Environment· Aug 28, 2026 · 2mo ago
Fremont, CA
In office
Full-time
Senior
$137K–$186K est.
10+ years exp
Job description
About Pacific Fusion
Pacific Fusion was founded in 2023 with the mission to power the world with abundant, affordable, clean energy.
We are rapidly designing and building a pulser-driven inertial fusion system to achieve net facility gain (more fusion energy output than stored energy input). In parallel, we are developing the key components required to build affordable fusion systems.
Our plans are ambitious. We have raised over $900M so far from incredible investors, resourcing us to deliver on these plans. We are bringing together the best scientists, engineers, and operators from the fusion community, hard tech industry, and other sectors. We are united by a shared sense of urgency to provide clean power for the world, particularly managing climate change while meeting growing global energy demand. You can read more about us in this letter from our founders . Why This Role Matters
This role is critical to design assembly and integration for testing key components of our pulser system.
What You'll Do
Design, analyze, and test advanced vacuum systems for target area chambers and diagnostics.
Select and size vacuum components, including pumps, seals, ducts, and valves, ensuring performance in particle-free cryogenic environments.
Rapid prototyping for fusion technology applications.
Lead technical and engineering activities from concept development through final onsite commissioning of vacuum equipment and systems.
Supporting high-voltage electrical switching operations and testing in a vacuum chamber
Perform experiments to characterize materials for outgassing, permeability, and vacuum compatibility.
Provide solutions to field issues related to vacuum system design and performance.
Collaborate cross-functionally to educate and negotiate design requirements within a multidisciplinary team.
What You Bring
Bachelor’s Degree in Mechanical, Aerospace Engineering or a related field, Master's or PhD is a plus. Alternatively, a minimum of 10 years specialized experience as a senior technician—with demonstrated responsibilities in system design, independent testing, and complex troubleshooting.
Proven expertise in high vacuum systems design, analysis, and construction.
Hands-on experience with vacuum components: chambers, pumps, seals, valves, ducts and clean room techniques.
Experience integrating electrical testing in vacuum systems and pressurized systems
Familiarity with ASME BPVC and B31.3 codes.
Experience with radioactive or toxic gas vacuum systems, novel vacuum pumps, or material characterization
Bonus Points For
Experience setting up wiring, circuits, control systems, diagnose electrical malfunctions and system failures using testing tools.
Machining and CAD design experience, CREO
Pay Range: $156,500 — $219,900 USD TOTAL COMPENSATION AND BENEFITS FOR ELIGIBLE EMPLOYEES
Industry-competitive salary
Equity plan
6% employer 401k matching
Generous paid time off (including sick leave, vacation, paid family leave)
Medical, Dental, and Vision insurance
Actual base salary offered will be determined by: experience, skills, and work location. This range is for base salary, our total compensation includes equity and benefits. We welcome you to apply even if your expectations are outside our listed range.
EQUAL OPPORTUNTITY
Pacific Fusion is committed to creating a diverse environment and is proud to be an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status.
Pacific Fusion is committed to providing reasonable accommodations for qualified individuals with disabilities in our job application procedures and throughout employment. If you need assistance or any accommodation, please let us know.
U.S. EXPORT CONTROL COMPLIANCE
This position may require access to information or technology that is subject to U.S. export control laws, such as ITAR or EAR. Under these regulations, we are required to ensure that such access is provided only to individuals who are classified as 'U.S. Persons.'This status includes U.S. citizens, U.S. nationals, lawful permanent residents (green card holders), and asylees and refugees with such status granted, not pending.
RECRUITING AGENCIES
Pacific Fusion does not accept unsolicited resumes from recruiters or employment agencies without a fully executed recruitment agreement in place. In the absence of such agreement, Pacific Fusion reserves the right to pursue and hire any candidates without an obligation to pay fees. Agencies are requested not to contact Pacific Fusion hiring managers or employees regarding recruiting services.
Application prep
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- Platform
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Benefits
Benefits detected in the listing.
Dental
Vision
401k
Paid Time Off