Senior Mechanical Engineer (Nuclear Reactor)

Location: Onsite in Torrance, California, United States. Applicants must be legally authorized to work in the United States as a U.S. citizen or lawful permanent resident.

Salary: $140,000–$180,000 USD annually

Company

hirify.global develops scalable, high-temperature nuclear power systems for industry, hydrogen, and next-generation manufacturing.

What you will do

• Own mechanical subsystem design from requirements and concept through detailed design and design freeze for the reactor, control rods, helium pressure boundary, helium services, HVAC, and Citadel.
• Perform and review stress, thermal, and fluid analyses, including FEA and CFD, to validate margins, materials, and code compliance.
• Develop 3D CAD models, assemblies, and drawings using GD&T and tolerance analysis.
• Take designs through procurement, vendor management, factory build, assembly, component and integrated testing, commissioning, and first operation.
• Design for manufacturing and repeatable production while collaborating with systems engineering, safety, IC&E, quality, supply chain, and V&V teams.
• Mentor junior engineers, contribute to standards and configuration management, and lead hardware root-cause investigations and corrective actions.

Requirements

• Bachelor’s degree in Mechanical Engineering or a related field.
• 5+ years of mechanical engineering experience with complex hardware such as pressure systems, heat-transfer equipment, mechanisms, or large structures.
• Proven experience taking hardware from design through build and test.
• Strong foundation in stress analysis, thermal design, materials, and pressure-vessel and piping codes.
• Proficiency with CAD tools such as SolidWorks, Creo, NX, or similar, and engineering drawing standards.
• Legal authorization to work in the United States as a U.S. citizen or lawful permanent resident.

Nice to have

• Master’s degree in Mechanical Engineering or a related field.
• Experience with high-temperature, high-pressure systems, including pressure vessels, heat exchangers, and piping.
• First-of-a-kind hardware experience in aerospace, power generation, oil and gas, or defense.
• Experience with helium or other gas systems, sealing, leak tightness, rotating equipment, precision mechanisms, actuators, and qualification testing.
• Working knowledge of ASME pressure-vessel and piping codes, including Section VIII and B31.3.
• Experience designing for manufacturing and scaling from prototype to series production.
• Nuclear industry experience in commercial, defense, or national-laboratory environments is a plus but not required.

Culture & Benefits

• High-impact startup environment with significant autonomy, ownership, and opportunities for rapid career growth.
• Equity ownership in an advanced energy company.
• Comprehensive medical benefits and unlimited PTO.
• Free daily lunch and dinner provided onsite, plus a generous PPE stipend.
• Direct collaboration with experienced operators, engineers, and industry leaders.