Senior Electrical Engineer, Integration & Test

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 Electrical Engineer, HIL to lead the design, build, and maintenance of Radiant’s electrical test infrastructure for Kaleidos, our commercial microreactor targeted for deployment in 2028.

You will own test infrastructure development, including Hardware-in-the-Loop (HIL) systems and other electrical test platforms, and drive integration and validation across critical systems. This role suits an experienced electrical engineer with deep hands-on test-infrastructure expertise, ready to own technical decisions across electrical integration, validation strategy, and test-environment development. You will shape the electrical test infrastructure supporting the first commercialized high-temperature gas-cooled portable microreactor.

Responsibilities and Duties:

Build the HIL platform from the ground up: plant simulation, real hardware-in-the-loop, and the test environment Kaleidos ultimately ships from.

Own the design, build, and maintenance of electrical test infrastructure, including test benches and new test platforms as the program scales.

Define electrical and software integration requirements across power distribution, signal conditioning, sensor mapping, actuator interfaces, and device simulation.

Own the communication layer between hardware, control systems, and software, including protocol selection, timing, and boundary fault behavior.

Lead the electrical validation strategy, developing and iterating the test procedures the program depends on rather than executing someone else’s.Assemble, debug, and troubleshoot test hardware and harnesses hands-on, with minimal guidance.

Execute test procedures, collect data, and lead analysis across multiple test environments.

Drive automation and tooling improvements, with real influence over how the team tests.

Lead design reviews and carry technical decisions to cross-functional stakeholders.

Required

Qualifications & Skills:

BS in Electrical Engineering or a related field.
5+ years of hands-on experience in electrical engineering, including hardware design, integration, and test.
3+ years developing hardware-in-the-loop (HIL) systems, including signal conditioning, DAQ/IO interfaces, and fixtures for validating embedded controls

Demonstrated experience owning and building electrical test infrastructure.

Proficiency with DAQ and test platforms such as dSpace, NI PXI, Speedgoat, or similar.

Hands-on experience with data acquisition, test execution, and validation frameworks.

Strong electrical and software debugging and troubleshooting skills.

Background in high-reliability, safety-critical, or regulated industry environments (aerospace, defense, nuclear, medical, or automotive).Desired

Qualifications & Skills:

Experience with real-time simulation systems and FPGA-based hardware.

Strong understanding of control fundamentals and software testing processes.

Experience with trace capture…