Principal Mechanical Design Engineer, Turbomachinery

Location: El Segundo, California, United States; 100% onsite at El Segundo HQ

Salary: $200,500–$314,475 annually, plus equity.

Company

hirify.global builds transportable, mass-produced nuclear microreactors, including the 1 MW Kaleidos reactor for critical infrastructure and commercial power applications.

What you will do

• Serve as the Responsible Engineer for the turbomachinery mechanical system and own the architecture of high-speed rotating assemblies.
• Lead rotor dynamics, structural integrity, life analysis, detailed component design, requirements flowdown, and technical decisions covering shafts, bearings, seals, materials, and clearances.
• Define tolerances, fits, stack-ups, alignment strategies, and interfaces across turbine, compressor, alternator, electrical, thermal, manufacturing, and test systems.
• Test and validate turbomachinery through spin testing, thermal testing, model correlation, performance verification, and system-level operation.
• Support assembly, integration, hardware bring-up, troubleshooting, root-cause analysis, and design iteration.
• Provide subject-matter expertise, technical guidance, design reviews, roadmap input, and risk mitigation without direct people-management responsibility.

Requirements

• B.S. in Mechanical Engineering or a related field.
• 10+ years of experience designing high-speed rotating machinery such as turbines, compressors, or similar systems.
• Deep expertise in turbomachinery mechanical design and structural analysis, including bearings, seals, and high-speed shafting.
• Expert-level proficiency with analysis tools such as ANSYS and advanced use of NX and Teamcenter.
• Strong understanding of tolerancing, GD&T, precision mechanical assembly, and system-level mechanical design.
• Experience owning hardware through design, build, and test cycles, including hands-on assembly, integration, and troubleshooting.
• Strong engineering judgment, mechanical intuition, communication, accountability, and ability to influence cross-functional teams without authority.
• Ability to work effectively in a fast-paced, first-of-a-kind development environment.
• Willingness to work extended hours and weekends as necessary and work 100% onsite at El Segundo HQ.

Nice to have

• Experience with closed-loop Brayton-cycle or similar energy systems.
• Familiarity with high-temperature materials and extreme-environment design.
• Experience integrating mechanical systems with high-speed electric machines.
• Prior experience as a Responsible Engineer for complex hardware.
• Experience scaling hardware from prototype to production.

Culture & Benefits

• Full-time employees receive an incentive stock plan, comprehensive medical, vision, dental, life, accident, hospital, critical illness, commuter, and FSA/HSA benefits.
• Eight weeks of paid parental leave for all parents, with additional paid pregnancy leave for California employees.
• Fully covered Nuclear Engineering Certificate Program through Penn State University for eligible employees.
• Flexible PTO, a remote workday allocation, catered lunch, snacks, drinks, and company and team events.
• The role involves access to technology subject to U.S. export controls; any offer is contingent on the applicant’s ability to comply with those controls.