Senior Software Engineer, Front End

Radiant Industries; El Segundo (CA); On-site; USD 150,000 - 230,000; Full time

Benefits offered by this job

Stock options

Medical coverage

One Medical

Vision coverage

Dental coverage

Other voluntary benefits

Parental leave

Job summary

Radiant, an El Segundo, CA-based startup, is seeking a Senior Software Engineer to own the frontend of our in-house telemetry and fleet management platform. You’ll join the Mission Software team, building on a highly technical telemetry streaming platform and adding features for engineers and operators to analyze data and configure our Kaleidos reactor.

The ideal candidate is outgoing, organized, and collaborates well with other engineers.

Qualifications

• Bachelor’s degree in CS, Engineering, Physics, or related field.
• 5+ years of professional web/frontend/GUI experience.
• Proficient in React + TypeScript for SPAs; Jest + Playwright for testing.
• Experience with CRDTs like Yjs.
• Experience building mission-critical systems using WebSockets, WebRTC, or SSE.
• Proven ability to drive complex UI features.
• Strong code review and debugging skills.

Responsibilities

• Own frontend parts of internal telemetry and fleet management platform using React + TS.
• Develop reliable, performant data review and analysis systems.
• Build frontend pages for device configuration and telemetry.
• Collaborate with Mission Software team and stakeholders across the company.

Skills

React + TypeScript

Web development

Frontend development

Real-time systems

WebSockets/WebRTC

Code review & debugging

Collaboration

Education

Bachelor's degree in CS/Engineering/Physics or related field

Tools

Jest

Playwright

TanStack Query

React Router

Pixi.js

WebGPU

Yjs

Job description

About Radiant

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, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. 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 leverages modern software engineering to rapidly deliver safe, factory‑built microreactors that use existing, well‑qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries 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.
• Our Tech Stack:

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 Jest + Playwright
• CRDTs like Yjs
• 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.

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.
• 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.

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.