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Senior Embedded Software Engineer

Radiant

Radiant

Software Engineering
El Segundo, CA, USA
USD 133,500-218,925 / year + Equity
Posted on Feb 27, 2026

Location

El Segundo HQ

Employment Type

Full time

Location Type

On-site

Department

EngineeringSoftware Engineering

Compensation

  • Annual Salary Range $133,500 – $218,925 • Offers Equity

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 next year, with initial customer deliveries beginning in 2028.

Senior Embedded Software Engineer

Radiant is seeking a Senior Embedded Software Engineer to design, develop, and test embedded software for instrumentation and control (I&C) systems. You will develop mission critical, highly performant embedded systems to interface with sensors and actuators. The candidate will be comfortable working in early design architectural stages and owning designs through production. You will have the opportunity to build mission critical software control systems for the first commercialized portable nuclear microreactor.

Responsibilities and Duties:

  • Design and build reliable, fault-tolerant embedded software for production hardware.

  • Develop and bring up new drivers for I&C hardware.

  • Lead design reviews, review and iterate on feedback.

  • Be a responsible engineer from architectural design through test, build and implementation.

  • Create robust testing plans and documentation.

Required Qualifications and Skills:

  • Bachelor’s degree in computer engineering, computer science, electrical engineering, or similar discipline from accredited institution.

  • 5+ years of industry experience on embedded software, including 1+ year of design and architecture experience.

  • Experience with an RTOS (Zephyr, NuttX, ThreadX, etc).

  • Proficient in C and C++

Desired Qualifications and Skills:

  • Experience with Zephyr RTOS.

  • Experience working with Simulink Autocode C++ export.

  • Experience with CMake.

  • Experience with FPGAs.

  • Comfortable reading hardware schematics.

  • Comfortable taking ownership of responsibilities and full design.

  • Comfortable working autonomously and proactively in day-to-day activities.

  • Strong communication with peers and management.

Benefits:

  • Cross-functional team with embedded software, FPGA, and hardware all together.

  • Opportunities for technical growth outside of pure software.

  • Opportunity to own designs from concept to completion.

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.

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.

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.

Compensation Range: $133,500 - $218,925