Senior Mechanical Engineer

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

Pacific Fusion is seeking an exceptional Senior Mechanical Engineer to help create the path to commercial fusion energy. You will help with the design, analysis, integration, and validation of mechanical systems and components across our advanced fusion energy platform. This role sits at the intersection of precision engineering and first-of-kind technology, demanding both deep technical expertise and the creative problem-solving mindset needed to tackle challenges no one has solved before. You will lead collaborative projects, mentor junior engineers, and play a vital role in driving our overall development effort.

What You'll Do

Develop innovative mechanical designs for complex engineering problems across our fusion systems, from vacuum vessels and structural assemblies to diagnostics hardware and experimental fixtures.

Lead design changes and improvements, owning components from concept through fabrication and test.

Work closely with vendors and manufacturers to ensure designs are practical, cost-effective, and manufacturable.

Perform mechanical analysis — including stress, thermal, and dynamic loading — to validate designs against requirements.

Conduct and participate in design reviews, providing critical feedback to improve system performance and reliability.

Coordinate with multidisciplinary teams spanning plasma physics, pulsed power, electrical, software, and manufacturing engineering to deliver integrated system-level designs.

Oversee the creation of detailed design documentation, drawings, and specifications.

Participate in risk assessments and develop mitigation strategies for novel engineering challenges.

Stay current with relevant advancements in mechanical design, materials, and manufacturing technologies.

What You Bring

Bachelor's degree in Mechanical Engineering required; Master's or PhD is a plus.

5+ years of experience as a Mechanical Engineer, ideally with exposure to complex, multi-disciplinary systems.

Proficiency in CAD software (Creo, SolidWorks, or equivalent) and strong 3D modeling habits.

Experience with Finite Element Analysis (FEA) for structural, thermal, or dynamic applications.

Proven track record of taking mechanical designs from concept through fabrication and test.

Strong understanding of manufacturing processes and design for manufacturability (DFM).

Excellent leadership skills with the ability to mentor and guide junior engineers.

Hands-on experience in laboratory or prototype environments — comfortable with rapid iteration and ambiguity.

Excellent written and verbal communication skills, including the ability to communicate trade-offs clearly across disciplines.

Bonus Points

Experience in fusion, plasma physics, accelerator physics, defense, or other high-consequence technical environments.

Familiarity with vacuum systems, cryogenics, high-voltage hardware, or pulsed power components.

Exposure to large-scale structural systems, pressure vessels, or custom capital equipment.

Pay Range: $138,100—$207,100 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.