Principal Electrical Engineer, Electronics

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.

Radiant is seeking a Principal or Staff Electrical Engineer to define and lead the electrical architecture for Kaleidos, our commercial microreactor targeted for customer deployment in 2028. The work spans end-to-end PCB development, mixed-signal design, high-speed interfaces, power distribution, and signal integrity for the data acquisition, signal conditioning, and real-time processing that reactor control depends on.
You will lead custom hardware, set design standards, drive architecture decisions, and own high-reliability, low-noise board development from requirements through layout, bring-up, validation, and field deployment. You will also shape the hardware roadmap and guide the electrical team’s technical direction as we scale toward first commercial deployments.

• Own the multilayer mixed-signal boards that control a fission reactor, terrestrial today with space applications ahead.

• Define the system-level electrical architecture for mixed-signal systems: power distribution, analog front ends, and digital control interfaces.

• Design, analyze, and simulate low-noise analog front ends and integrate them with ADC/DAC, DSP, and digital subsystems.

• Own schematic capture, component selection, and layout, including high-speed and precision routing for sensor interfaces, data acquisition, and communication buses, with focus on signal integrity, power integrity, grounding, and EMI/EMC.

• Bring up, debug, and validate hardware hands-on, and write and execute the qualification plans that prove performance, reliability, and environmental margin.

• Work directly with firmware, FPGA, and DSP engineers at the hardware-software boundary, and with customers and interdisciplinary teams.

• Lead design reviews, mentor the electrical team, and own hardware risk identification and mitigation.

• Bachelor’s degree in Electrical Engineering or a related field.

• 8+ years designing custom multilayer and mixed-signal PCBs.

• Experience shipping hardware you designed, with ownership across most of the lifecycle, from requirements through layout, bring-up, and qualification for production or field use.

• Demonstrated experience setting electrical architecture direction and driving decisions across complex, multi-disciplinary programs and with customers.

• System-level perspective across design analysis, fabrication, and testing.

• DSP experience applied to data acquisition and real-time signal processing.

• Circuit analysis and simulation experience (PSpice, LTspice).

• Strong schematic capture and PCB layout experience (Altium Designer, Cadence, or similar), including component selection.

• Strong command of signal integrity, power integrity, and grounding.

• Analog and mixed-signal design experience, including sensor interfaces, ADC/DAC integration, and low-noise practices.

• Familiarity with high-speed interfaces (SPI, I2C, UART, Ethernet) and their layout constraints.

• Hands-on board bring-up, troubleshooting, and lab instrumentation (oscilloscopes, spectrum analyzers, VNAs).

• EMI/EMC mitigation experience.

• Experience designing for high-reliability or harsh environments (nuclear, aerospace, defense, or industrial).

• Master’s degree in Electrical Engineering or a related field.

• Radiation effects and radiation-tolerant electronics design.

• Power electronics or power distribution design.

• FPGA or embedded systems exposure supporting hardware/software co-design.

• Nuclear instrumentation or detector interface electronics.

• DFM, DFT, and production bring-up experience.

• Must be willing to work extended hours and weekends as necessary to accomplish our mission.

• Must work 100% onsite at El Segundo HQ.

• 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 full-time 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: [email protected].
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.