Senior Mechanical Design Engineer - Reactor Module

Oklo Inc. is developing fast fission power plants to deliver clean, reliable, and affordable energy at scale. They are seeking a Senior Mechanical Design Engineer to design critical hardware for advanced fast reactors, ensuring performance and compliance with industry standards.

Responsibilities:

• Develop and own the design of complex mechanical components and subsystems within the reactor module
• Collaborate cross-functionally with other engineering teams to define design and functional requirements, ensuring compliance with safety regulations and industry codes standards (e.g., ASME BPVC)
• Use CAD tools to translate functional requirements into robust designs that meet structural, thermal, and integration constraints
• Conduct and participate in design reviews, providing and receiving technical feedback
• Rigorously evaluate mechanical designs to identify deficiencies and proactively propose and implement solutions
• Generate and maintain detailed 3D CAD models, 2D drawings, and bills of materials using controlled processes in PDM/PLM systems
• Coordinate closely with analysis teams to guide and interpret thermal, structural, fatigue, and safety analyses in support of design validation
• Perform detailed manufacturability reviews, tolerance studies, and DFM/DFA assessments to prepare components for fabrication and assembly
• Create and maintain clear, well-written engineering documentation, including design rationales, functional requirements, reviews of historical designs, and detailed explanations of system architecture and performance
• Work closely with fabrication partners to refine designs for cost-effective and practical production
• Manage engagements with consultants and engineering firms to support high-fidelity analysis, ASME code compliance, and design maturity advancement
• Contribute to continuous improvement of Oklo’s mechanical design processes, tools, and standards through feedback and development of best practices

Requirements:

• Bachelor's or higher degree in Mechanical Engineering or a related engineering discipline
• 8+ years of industry experience in mechanical or structural design within sectors such as aerospace, automotive, energy, or industrial equipment
• Proficiency in 3D CAD modeling software (e.g., Siemens NX, CATIA, SolidWorks), including part modeling, large assemblies, and detailed drawings
• Experience with design control using PDM/PLM tools (e.g., Siemens Teamcenter, SolidWorks PDM, Windchill)
• Robust understanding of mechanical design principles, including DFM (Design for Manufacturability), DFA (Design for Assembly), and tolerance stack-up analysis
• Ability to interpret and produce engineering drawings that apply GD&T in line with ASME Y14.5 or similar standards
• Working knowledge of material selection (particularly metals), manufacturing methods, and fabrication techniques
• Demonstrated ability to collaborate on cross-functional teams, integrating feedback from analysis, manufacturing, and systems engineering
• Strong written and verbal communication skills, with the ability to clearly document and present engineering work
• Experience designing large structural weldments and mechanical joints
• Familiarity with the ASME Boiler and Pressure Vessel Code, particularly Sections III or VIII
• Background in designing components for high-integrity or safety-critical systems (e.g., nuclear, aerospace, defense, or heavy industry)
• Proven ability to lead hardware projects through the full development cycle—from concept and design to testing and production
• Comfortable working with external manufacturers and engineering consultants for fabrication and analysis support
• Knowledge of large scale fabrication techniques and transportation/handling of large components
• Understanding of thermal-mechanical analysis principles, with experience designing for high-temperature environments
• Basic knowledge of nuclear fission and radiation effects on materials and components