Summer 2026 Internship - Software Engineering

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 Engineering Internship

Radiant is seeking a motivated Software Engineering Intern with a strong computer science foundation to join our team. As an intern, you will work alongside mechanical, electrical, and nuclear engineers to assist in developing software tools that support simulation and analysis for reactor design, development, and safety analysis. This is an excellent opportunity to gain hands-on software development experience in a highly interdisciplinary environment.

Please note : we plan to begin interviewing for Summer 2026 internships in November / December.

Responsibilities and Duties :

• Assist in creating tooling to support a variety of simulation software packages.
• Contribute to internal software products that support simulation and analysis of simulation results.

Required Qualifications and Skills :

Desired Qualifications and Skills :

Additional Information :

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 :

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.