Mechanical Designer (Plant Layout & Piping Systems)

General Matter, Inc. is an American nuclear energy company based in California that is focused on developing domestic nuclear energy solutions. The company aims to harness nuclear technology to increase national energy prosperity, reduce dependence on foreign energy sources, and support the expansion of American capabilities in the energy sector. Their work centers on making nuclear energy more accessible and practical by advancing technologies that can be developed and deployed within the United States. General Matter's mission is rooted in the belief that nuclear power represents a critical pathway toward a cleaner, more energy-independent future. By turning domestic nuclear potential into operational reality, the company positions itself at the intersection of national security, economic growth, and climate-conscious energy production. Their approach emphasizes building nuclear energy infrastructure that is homegrown rather than reliant on foreign supply chains or expertise. The company brings together leaders from nuclear engineering, technology, government, and finance, reflecting a multidisciplinary approach to solving the complex challenges of modern nuclear energy development. As a startup operating in the green and climate technology sector, General Matter represents a new wave of private investment in nuclear energy as a viable and scalable low-carbon power source for the United States.

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 
We are seeking a Mechanical Designer to develop and maintain the 3D CAD model for piping and mechanical systems in a complex nuclear enrichment facility. This role emphasizes detailed routing, spatial integration, and layout optimization, ensuring designs are accurate, constructible, and coordinated across disciplines. The ideal candidate has strong plant design software expertise and experience translating design intent into precise, model-centric layouts. 

Responsibilities 

• Own and maintain the 3D CAD model for piping and mechanical systems, ensuring alignment with process and mechanical specifications.
• Develop, update, and maintain piping component libraries, data attributes, tagging, and system standards to ensure consistency between P&IDs, 3D models, and documentation.
• Perform detailed routing of pipes, valves, specialty components, and supports, considering space constraints, accessibility, maintainability, and constructability.
• Coordinate with structural, HVAC, and electrical systems to avoid clashes and optimize layouts.
• Conduct clash detection and interdisciplinary model reviews using plant design tools.
• Produce isometric drawings, general arrangement drawings, spool sheets, and installation documentation for fabrication and construction.
• Define spool breaks and support modular construction where applicable.
• Collaborate with engineers to ensure design intent, constructability, and field installation requirements are incorporated.
• Maintain as-built documentation and update models throughout the project lifecycle. 

Basic Qualifications 

• Associate’s degree or equivalent experience in Mechanical Design, Drafting, or related field.
• 3+ years of hands-on experience modeling piping systems in 3D plant design platforms.
• Proficiency with plant design software (e.g., AutoCAD Plant 3D, AVEVA E3D, SmartPlant 3D, CADWorx, or similar).
• Strong understanding of piping systems, mechanical components, and industrial layout principles.
• Ability to interpret P&IDs and specifications into accurate 3D models.
• Experience producing piping isometrics, general arrangement drawings, and fabrication documentation. 

Preferred Skills 

• Experience in nuclear, chemical, petrochemical, or other complex industrial facilities.
• Familiarity with spec-driven piping, automated part selection, and component catalogs.
• Knowledge of piping line numbering, tagging systems, and engineering data attributes.
• Experience modeling pipe supports, equipment connections, and maintenance clearances in dense layouts.
• Familiarity with model coordination and clash detection tools (e.g., Navisworks).
• Understanding of fabrication and field installation practices, including spool breaks and field fit.
• Ability to thrive in fast-paced, multidisciplinary environments. 
  

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 $80,000-$170,000 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.