Mechanical Design Engineer - Plant Piping Systems

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. Mechanical Design Engineer - Plant Piping Systems General Matter is seeking a Mechanical Design Engineer to transform conceptual process designs into fully engineered systems for a large-scale nuclear enrichment facility. This role focuses on detailed mechanical design, including piping systems, component selection, and structural analysis, ensuring that complex process architectures are realized safely and reliably. The ideal candidate will combine expertise in mechanical engineering fundamentals with experience in high-hazard or industrial plant environments, delivering robust solutions for advanced nuclear energy production. Responsibilities * Translate P&IDs and process architecture outputs into detailed mechanical designs for piping and equipment systems. * Perform component sizing and selection (pipes, valves, fittings, supports) based on process conditions (flow, temperature, pressure). * Collaborate on routing plans and layouts for piping systems, ensuring efficient and maintainable configurations. * Conduct structural and flow analysis to validate mechanical integrity and performance under operating conditions. * Specify materials, thicknesses, and support methods to meet safety, regulatory, and operational requirements. * Prepare detailed engineering drawings, BOMs, and procurement specifications for mechanical systems. * Select components that meet technical requirements while considering availability and lead times, ensuring designs can be executed on schedule without compromising quality or safety. * Collaborate with process engineers, structural engineers, and procurement teams to ensure seamless integration of designs. * Participate in design reviews and risk assessments, providing technical justification for design decisions. * Support installation planning and provide technical oversight during construction phases as needed. Basic Qualifications

• Bachelor’s degree in Mechanical Engineering or a related field.
• 3+ years of experience in mechanical design for industrial plants, chemical

facilities, or similar high-hazard environments. * Strong understanding of fluid mechanics, structural analysis, and material selection. * Proficiency in piping design standards (ASME, ANSI, or equivalent) and familiarity with pressure vessel codes.

• Experience with CAD tools for mechanical design and layout.
• Ability to interpret P&IDs and process documentation and translate them into

detailed mechanical designs. * Excellent problem-solving and communication skills for cross-functional collaboration. * Evidence of exceptional ability (prior projects, portfolio of work, completed products, etc). Preferred Skills and Experience * Experience in nuclear, chemical, petrochemical, or gas processing facilities. * Familiarity with stress analysis tools and piping flexibility analysis (e.g., Caesar II or similar).

• Knowledge of compressible flow, vacuum systems, and cryogenic piping design.
• Procurement experience for large-scale facilities, including vendor

engagement and managing long-lead components. * Ability to thrive in a fast-paced, multidisciplinary environment, balancing technical rigor with practical 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 $90,000–$175,000 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.