Senior Software Engineer, Frontend

About Radiant

Radiant is an El Segundo, CA-based company building the world's only mass-produced, transportable nuclear microreactors. The U.S. grid is under growing strain, with power demand accelerating, driving higher utility costs, rising carbon emissions, and interconnection backlogs. Radiant has a solution, transportable, on-site power. Our first reactor, Kaleidos, is 1 megawatt: small enough to be factory-built, transported by land, sea, or air, and deployed wherever power is needed. 1 MW can power 1000 homes for five years. Ship it back and we refuel for a 20 year operating life. We made energy a product that can be used for critical infrastructure like military bases, data centers, hospitals, and remote sites, as well as the commercial main street businesses that keep America running. Founded in 2020, Radiant is under contract to deliver power to the U.S. Army, Navy and Air Force and has signed pre-order agreements with Equinix, with deployments beginning in 2028.

About the Role

Radiant is seeking a Senior Software Engineer to own the frontend for our in-house telemetry and fleet management platform. You’ll join the Mission Software team, build on top of a highly technical telemetry streaming platform, and work on fleet monitoring systems for Radiant’s portable nuclear reactor, Kaleidos. You’ll also build additional features for engineers and operators, adding new data analysis and configuration capabilities to a critical platform. The ideal candidate is outgoing and organized, ready to collaborate with other engineers. The code you write will help design, run, and mass-produce the first high-temperature gas-cooled portable microreactor ever to be commercialized.

Responsibilities & Duties

• Own critical parts of the frontend for our internal telemetry and fleet management platform, working in a modern React + TypeScript + Vite codebase.

• Develop highly reliable, performant systems for data review and analysis.

• Develop frontend pages for complex device configuration and telemetry systems.

• Collaborate with other members of the Mission Software team and reach consensus among stakeholders across the company.

Required Qualifications & Skills

• Bachelor's degree in Computer Science, Engineering, Physics, or a related technical field.

• 5+ years of professional experience in web development, frontend development, and / or desktop GUI development.

• Proficient in using React + TypeScript for SPAs, testing with Vitest + Playwright

• Experience building highly performant, complex, mission-critical systems using technologies like WebSockets, WebRTC, or SSE.

• Has worked on a complicated UI system before, driving forward critical features

• Strong code review & debugging skills.

Desired Qualifications & Skills

• Experience using the following technologies: TanStack Query + React Router, Pixi.js + WebGPU, Yjs or similar CRDT

• HMI or dashboarding design experience

• Hands-on hardware tech experience, working closely with hardware engineers to develop deeply coupled applications.

Our Tech Stack:

• Typescript

• React

• Vite

• Pixi.js & Yjs

• Rust + Axum Web / Python + FastAPI

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.

Benefits and Perks

• 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.

• Nuclear Engineering Certificate Program: 100% covered educational program with Penn State University, for eligible employees, to rapidly upscale into nuclear.

• 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.

Total Compensation and Benefits
Radiant compensates people for impact and invests in those who continue to raise the bar. Radiant’s new hire compensation package includes base salary, substantial equity grants, and comprehensive health benefits. Total compensation and level are determined through a rigorous evaluation of interview performance, experience, education, and qualifications, and are designed to support continued growth as scope, responsibility, and impact expand at Radiant.

The best of today’s advanced reactor builders don’t wait for job postings. They join the winning team. If that’s you, contact us directly for immediate opportunities: recruiting@radiantnuclear.com.

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.

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.