Mechanical Engineer

El Segundo, CA

Radiant Industries is an El Segundo, CA-based startup developing Kaleidos, a portable, containerized nuclear microreactor. Portable nuclear power with rapid deploy capability can replace diesel generators used today to provide critical asset support for hospitals, datacenters, and military bases or to power microgrids at remote sites. Radiant’s unique yet practical approach to nuclear development utilizes modern software engineering to rapidly achieve safe, factory-constructable microreactors leveraging existing, well-qualified materials. Radiant is on a fast track to demonstrate the first fueled operation of a new commercial nuclear reactor design, just four years from now. 

Radiant is seeking a highly motivated mechanical engineer for an opportunity to work with mentorship and guidance from experienced engineering professionals in a fast-paced startup environment.  The candidate will be responsible for various aspects of core structures and component development as priorities shift and expertise is gained.   

Responsibilities & Duties 

  • Engineering ownership of Mechanical Design, examples:

    • Reactor core pressure vessel design per Boiler & Pressure Vessel Code (BPVC) 

    • Reactor internal components and mechanisms 

    • Radiation shielding and thermal insulation

    • Fluid Power and Electrical system components, structural mounts 

    • Transportation and Assembly tooling 

  • Conduct structural analysis for the purposes of sizing and margin verification. 

  • Develop and execute manufacturing, assembly, and test plans. 

  • Create and manage a Bill-Of-Materials (BOM).

    • Find and develop suppliers for all components. 

    • Own subassembly design, manufacturing, and test schedules.  

  • Own risk analysis (FMEA) for subsystems. 

  • Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.  

 Required Qualifications & Skills 

  • Bachelor’s degree in mechanical engineering or similar field from an accredited institution. 

  • Experience with CAD and FEA software packages. 

  • Ability to relocate to Radiant’s office in El Segundo, CA (Greater Los Angeles Area). 

  • Ability to work or gain permission to work on export - controlled technologies based in the United States. 


Desired Qualifications & Skills 

  • Solid understanding and application of geometric dimensioning and tolerancing (GD&T). 

  • Self-motivated with strong organizational, written, and oral communication skills. 

  • Solid first-principles analysis skillset:

    • Proficiency with both “hand calc” analytical methods and higher fidelity Finite Element based analysis methods. Track record of appropriate fidelity selection, based on engineering questions to be answered. 

    • Able to efficiently and accurately derive free-body diagram-based models and control volume-based models for systems with which one was not previously familiar. 

  • 3+ years of professional experience designing hardware that was manufactured, deployed, and iteratively improved. 

  • 2+ years of experience using structural Finite Element Model (FEM) packages: NASTRAN, ANSYS, ABAQUS, or similar in the context of product design. 

    • Able to validate results against known analytical solutions. 

  • At least 1 year of software development experience:

    • C, C++, or Python development experience is preferred.

    • Prior use of code repositories, unit testing, performance benchmarking, and software review / release processes. 

    • Familiarity with good documentation practices and implementation of style guidelines.

  • Recent graduates may apply to this post too. 



Stock: Substantial incentive stock plan for all salaried employees 

Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans. 

Vision: 100% coverage + 50% for dependents 

Dental: 100% coverage, orthodontia extra, 50% for dependents 

Voluntary Life, Accident, Hospital, Critical Illness, Commuter and FSA are offered as employee contributed benefits. 

Vacation/Sick time