Director of Mechanical Engineering (Nuclear Reactor)

Location: Torrance, California, United States; onsite work

Salary: $240,000–$325,000 USD

Company

hirify.global develops scalable, high-temperature nuclear power for industry, hydrogen, and next-generation manufacturing. The Numenor team is building a flagship reactor program spanning the reactor core, helium systems, cooling, plant modules, and the Citadel.

What you will do

• Build and lead the mechanical engineering organization, including engineering managers and responsible engineers.
• Own the mechanical design basis for the reactor, primary helium loop, cavity cooling, helium services, plant modules, and related systems.
• Make final technical decisions on design acceptability, margins, materials, and code selection; lead design reviews and gate decisions through design freeze.
• Take designs through procurement specifications, factory build, assembly, integrated testing, commissioning, and first operation.
• Define verification and validation strategy with the V&V lead and design for manufacturing and repeatable production.
• Manage mechanical scope, schedule, budget, team structure, staffing, and coordination with systems engineering, safety, IC&E, quality, and supply chain.

Requirements

• 10+ years of mechanical engineering experience with complex hardware such as pressure systems, heat transfer equipment, mechanisms, or large structures.
• Hands-on experience as a technical authority signing off designs, setting margins, and owning design decisions.
• Experience leading mechanical scope for first-of-a-kind hardware from concept through build, test, and commissioning.
• Strong foundation in stress analysis, thermal design, materials, and pressure vessel and piping codes.
• Experience managing mechanical engineering teams, including managers, and key vendor relationships across multiple project phases.
• Must be legally authorized to work in the United States as a U.S. citizen or lawful permanent resident (green card holder).

Nice to have

• Experience with high-temperature, high-pressure systems, including pressure vessels, heat exchangers, and piping.
• First-of-a-kind hardware delivery from design through build and test 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 with design for manufacture and scaling from prototype to series production.
• Nuclear industry experience in commercial, defense, or national laboratory settings.
• Mechanical PE license.

Culture & Benefits

• Competitive base salary and equity ownership in a rapidly growing advanced energy startup.
• Comprehensive medical benefits and unlimited PTO.
• Free daily lunch and dinner provided onsite, plus a generous PPE stipend.
• High-impact environment with significant ownership, autonomy, and opportunities for rapid career growth.
• Direct collaboration with experienced operators, engineers, and industry leaders while building transformative energy technology.