Posted by the employer · Los Angeles, United States
Mechanical Engineer - Optomechanical Systems
General Matter · Los Angeles · United States
Posted: 9/17/2026 · On the employer's job feed since 10/11/2026
The advert
Quoted in full from General Matter's job posting. Gavroche does not edit it.
About the Company
General Matter enriches uranium.
We are designing, building, and operating the world’s lowest-cost enrichment services, here in the US.
In the process, we are restoring America’s ability to produce nuclear fuel to power AI, advanced manufacturing and critical industries our country relies on to remain competitive.
Fuel drives the cost of advanced reactor electricity production, and enrichment drives the cost of the fuel that advanced reactors consume. Reliable, low-cost enrichment is the catalyst for the nuclear Renaissance now under way.
Our mission is to make nuclear not only the cleanest and safest source of baseload power, but also the most affordable. We believe abundant nuclear energy will lead to a post-scarcity society.
We were incubated inside Founders Fund, like Anduril and Palantir before us, and are backed by over a dozen of the world's top venture capital firms.
Our lean, world-class team of engineers and operators is applying a first-principles approach to solving the problem of nuclear fuel production.
We are a mission-driven company with a culture of urgency, accountability, and transparency.
Help us build a high-energy society by making the cleanest, safest form of baseload energy the most affordable.
About This Role
As a General Matter Mechanical Engineer, you will design, build, test, and own the mechanisms and mechanical structures enabling our next-generation enrichment technology — including precision optical and photonic subsystems, beam delivery hardware, and components that must survive demanding thermal, chemical, and material-compatibility conditions unique to uranium processing. You will work closely with cross-functional teams, including electrical engineers, optical engineers, software engineers, chemical engineers, manufacturing engineers, nuclear engineers, materials scientists, metallurgists, and physicists. If you seek high impact and are excited by fast-paced, intense, Skunkworks-style projects at the frontier of enrichment technology, we encourage you to apply to join our team.
Responsibilities
- Develop mechanisms and mechanical structures for enrichment — including precision mounts, alignment stages, beam delivery paths, or enclosures for optical and photonic subsystems — and own them through the entire product lifecycle including requirements definition, design, development, qualification, and release to production.
- Select and specify materials and coatings for enrichment hardware based on mechanical, thermal, optical, and corrosion/wear performance requirements.
- Support optimization of designs for cost, performance, and manufacturability.
- Functionally test your hardware through thermal, vibe, shock, durability, etc., including precision alignment and beam pointing/stability testing for optical assemblies.
- Perform root-cause analysis on test failures and develop hardware mitigations.
- Collaborate with materials scientists and metallurgists to characterize material behavior under process-relevant conditions — including exposure to high-energy optical sources — and translate findings into design decisions.
- Participate in design review and provide feedback to ensure design objectives are met.
- Work closely with electrical, optical, software, manufacturing, and nuclear engineers to ensure designs are effectively integrated with overall system requirements.
Preferred Skills and Experience
- Background or working knowledge in materials science or metallurgy, particularly failure analysis, material selection, or performance of metals/alloys under extreme thermal, mechanical, or corrosive conditions.
- Experience designing precision mechanical structures for optical or photonic-based (e.g., alignment stages, athermal mounts, beam delivery paths, thermal management for high-energy optical components).
- Strong understanding of engineering fundamentals.
- Ability to perform trade studies and make clear recommendations using first principles and engineering fundamentals even with partial information.
- Experience in a fast-paced engineering environment or a highly technical role requiring a resourceful, entrepreneurial approach to complete tasks within tight timeframes or budget constraints.
Additional Requirements
- Ability to work extended hours and weekends as necessary.
Equal Opportunity Employer
General Matter is an Equal Opportunity Employer; employment with General Matter is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.
Compensation and Benefits
The base salary range for this role is $140k-$220k annually.
Compensation bands are determined by role, level, location, and alignment with market data. Individual level and base pay is determined on a case-by-case basis and may vary based on job-related skills, education, experience, technical capabilities and internal equity. Please note that the stated salary range is an estimate and may be adjusted based on market conditions, business needs, or other factors. In addition to base salary, for full-time hires, you may also be eligible for long-term incentives, in the form of stock options, and access to medical, vision & dental coverage as well as access to a 401(k) retirement plan.
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