Senior Software Engineer - Simulation

Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt failsafe microreactor that can be transported anywhere power is needed and run for up to five years without the need to refuel. Portable nuclear power with rapid deploy capability can replace similar-sized diesel generators, and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development utilizes modern software engineering to rapidly achieve safe, factory-built microreactors that leverage existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor next year at the Idaho National Laboratory, with initial customer deliveries beginning in 2028.

Software Engineer - Simulation Radiant is seeking a highly driven Software Engineer with a strong physics or mechanical engineering background. You will collaborate with mechanical, electrical, and nuclear teams to simulate physical systems with an appropriate degree of fidelity, write software that can be deployed to production hardware, and improve our simulation and test software stack, including our cutting-edge, custom-built Digital Twin system. You will have an opportunity to work in an interdisciplinary environment with a high degree of ownership and drive milestones forward to unlock commercialization of the first mass-produced nuclear reactor.

Responsibilities And Duties

• Develop models to simulate reactor physics, thermal hydraulics, and other Kaleidos systems.
• Improve thermal fidelity of reactor components in the Digital Twin.
• Collaborate across teams to accelerate software-in-the-loop and hardware-in-the-loop testing.
• Own mission-critical internal products and tooling.
  
  

Required Qualifications and Skills:

• Bachelor's degree in physics, mechanical engineering, or similar field from an accredited institution.
• 4 years of professional experience in Python, C#, C , or similar object-oriented programming languages.
• Familiarity with software development and documentation best practices, including version control in Git.
  
  

Desired Qualifications and Skills:

• Advanced degree (Master's or Ph.D.) in physics, mechanical engineering, or similar field from an accredited institution.
• Highly self-motivated with strong communication skills.
• Experience writing or contributing to simulation tools.
• Experience with distributed software development and familiarity with common design patterns.
• Interest in physics, hardware, and electrical engineering.
  
  

Additional Requirements:

• Must be willing to work extended hours and weekends as necessary to accomplish our mission.
• Must work 100% onsite at El Segundo HQ.
  
  

Total Compensation And Benefits

Radiant's new hire compensation package includes base salary, substantial equity grants, and comprehensive benefits. Total compensation and level are determined through a holistic evaluation of your interview performance, experience, education, and qualifications.

Benefits And Perks For Eligible Employees

• Stock: Substantial incentive stock plan for all full-time employees.
• Medical: 100% up to base silver level plan for employee 50% dependents, offers up to Platinum plans.
• One Medical: Sponsored memberships for employees and their dependents.
• Vision: 100% top tier plan coverage 50% for dependents.
• Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
• Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.
• 8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.
• Daily catered lunch. Free snacks and drinks.
• Flexible PTO policy. Remote workday allocation.
• Company and team-bonding events, happy hours and in-person camaraderie.
• Beautiful El Segundo headquarters close to the Pacific Ocean.
  
  

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time.

This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.