---
title: 'Principal Electrical Engineer, HIL (hardware-in-the-loop) at Radiant Industries'
canonical: 'https://feeny.ai/job/principal-electrical-engineer-hil-hardware-in-the-loop-radiant-industries-el-v2j2z5s8j1gx'
type: 'job'
last_seen: '2026-11-09'
---

# Principal Electrical Engineer, HIL (hardware-in-the-loop) at Radiant Industries

- **Company:** [Radiant Industries](https://feeny.ai/companies/radiant-industries)
- **Location:** El Segundo, CA
- **Compensation:** $201k–$314k
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-06-16
- **Last confirmed live:** 2026-11-09
- **Apply:** https://jobs.ashbyhq.com/radiant-industries/8a4ce348-8733-4384-86d4-90c98bc18f27/application

**Skills:** Electrical Engineering, Hardware Design, Integration, Test, DAQ, NI PXI, dSpace, Speedgoat, LabVIEW, TestStand, Python, C++, C#, Real-time simulation systems, FPGA-based hardware, Controls fundamentals, Trace capture, Data analysis tools

> Lead electrical system architecture and test infrastructure for Kaleidos microreactor deployment. Own end-to-end electrical integration, validation strategy, and hardware bring-up while managing schedules, budgets, and cross-functional technical decisions.

## Job description

## 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 Principal Electrical Engineer, HIL to lead the electrical system architecture and test infrastructure for Kaleidos, our commercial microreactor targeted for deployment in 2028. You will own end-to-end electrical integration, from architecture and requirements definition through hardware bring-up, testing, and commissioning, and lead the development of Hardware-in-the-Loop (HIL) systems and the broader test environment that validates the reactor before it reaches the field. As the technical authority across electrical integration and validation strategy, you will set direction independently while collaborating across mechanical, software, and systems engineering. You will define the electrical architecture behind the first commercialized portable microreactor as we begin deploying to our customers in 2028.

Responsibilities & 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, establishing it as a foundational asset for validating the commercial unit ahead of 2028.
- Define and own 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 protocol selection, timing, and fault behavior at the boundaries.
- Define and drive the electrical validation strategy, developing the test procedures and methodologies the program depends on.
- Own schedule, budget, and vendor management for electrical hardware and integration activities.
- Drive automation and tooling improvements, with real influence over how the team tests.
- Lead design reviews and carry technical decisions to stakeholders across electrical integration, embedded, software, and controls.

Required Qualifications & Skills:

- BS in Electrical Engineering, Mechanical Engineering, Computer Engineering or a related discipline.
- 8+ years of progressive engineering experience across hardware, controls, or test systems, with hands-on design, integration, and validation.
- 5+ years developing hardware-in-the-loop (HIL) systems, including signal conditioning, DAQ/IO interfaces, plant model integration, and embedded controls validation.
- Demonstrated experience setting technical direction, mentoring engineers, and driving programs with significant scope and ambiguity.
- Proven ability to deliver a functional product that meets requirements under tight timelines.
- Experience with DAQ and test systems (NI PXI, dSPACE, Speedgoat, or similar), including test execution and validation frameworks.
- Proficiency with test software and scripting environments (LabVIEW, TestStand) and at least one programming language (Python, C++, C#, or similar).
- Strong electrical and software debugging and root cause analysis skills.
- Experience working cross-functionally with software, mechanical, and systems engineering teams.
- Background in high-reliability, safety-critical, or regulated environments (aerospace, defense, nuclear, medical, or automotive).

Desired Qualifications & Skills:

- MS in Electrical Engineering or a related discipline.
- Familiarity with real-time simulation systems and/or FPGA-based hardware.
- Experience with controls fundamentals and software testing processes.
- Hands-on experience with trace capture, data acquisition, and analysis tools.

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 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: 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.

## About Radiant Industries

## Company Overview
- **One-liner**: Radiant Industries is building the world’s first mass‑produced, portable nuclear microreactor (Kaleidos) to replace diesel generators with zero‑emission, resilient power for remote sites, hospitals, data centers, and military installations.
- **Entity Type**: Private (Series D – $300M raised in December 2025, led by Lockheed Martin Ventures)
- **Headquarters**: El Segundo, California, USA
- **Founded**: 2020 (some sources list 2019)
- **Founders**: Not publicly disclosed

## Core Business
- **Primary industry**: Nuclear electric power generation / clean energy
- **Target customers**: B2B – remote communities, hospitals, data centers, military bases, industrial sites that currently rely on diesel generators or unstable grids
- **Mission**: To bring one of the world’s first factory‑constructed microreactors to market, providing portable, zero‑emissions power anywhere, anytime.

## Products & Services
- **[Kaleidos Microreactor](https://www.radiantnuclear.com/)**: A 1 MW electric / 1.9 MW thermal portable nuclear reactor packaged in a shipping container. It uses helium gas cooling and TRISO fuel (meltdown‑proof ceramic uranium particles). Delivered by truck or aircraft, installed without site excavation, and can reach full power the next day. After 5+ years the entire container is returned to the factory for refueling; up to four fuel cycles yield a 20‑year product lifetime. Customers purchase via Power Purchase Agreements (PPAs) or direct unit sales.

## Market Standing
- **Valuation / Market Cap**: Not disclosed
- **Key Metric**: Total funding raised – **$622.6M** (as of early 2026)
- **Notable Investors/Partners**: Andreessen Horowitz (led Series B), Lockheed Martin Ventures (led Series D), plus 18+ other investors across Series B, C, and D rounds
- **Growth Signals**:
  - Headcount grew **141% YoY** to 157 employees (as of mid‑2026)
  - 64 active job postings (+178% YoY)
  - Plans to test its development reactor in **2026** – which would be the first new commercial reactor design to achieve a fueled test in over 50 years
  - Initial customer deployments targeted for **2028**
  - SBIR Phase II awards from the U.S. Air Force for nuclear microreactor installation energy resilience

## Competitive Advantages
- **Portability & speed**: Delivered in a standard shipping container, installed in one day, no on‑site water or excavation needed.
- **Passive safety**: TRISO fuel is meltdown‑proof; the core is cooled by natural convection (air jacket) without pumps.
- **Factory‑built, factory‑refueled**: No nuclear waste or infrastructure left on site after the container is returned.
- **High energy density**: Over 110× the energy density of existing diesel systems.
- **Fleet monitoring**: Hundreds of units can be monitored 24/7 from a centralized control center.

## Strategic Focus
- Complete fueled testing of the Kaleidos prototype in 2026.
- Secure regulatory approvals (special nuclear material license, Part 7 license).
- Scale manufacturing for initial customer deployments beginning in 2028.
- Expand into military, commercial, and humanitarian markets (disaster relief, remote microgrids, backup power).

## Why Work Here
- **Culture & mission**: High‑impact climate tech – directly replacing diesel generators with clean nuclear power. Rated 5.0/5.0 on employer reviews (5 reviews) with strong scores for culture (4.7) and career growth (4.8).
- **Work location**: On‑site in El Segundo, CA (steps from the Pacific Ocean, near downtown). Employees work from a physical office.
- **Perks**: Company equity, relocation assistance, free daily meals, commuter benefits, onsite parking, generous parental leave, family medical leave, onsite Mother’s Room, dental/health insurance, FSA.
- **Diversity & inclusion**: Mandated unconscious bias training; hiring practices that promote diversity.
- **Tech stack**: React, TypeScript, Python, C++, C#, Kubernetes, Docker, PostgreSQL, AWS, Ansys, SolidWorks, Altium, and more. Engineers work on cutting‑edge nuclear, mechanical, and embedded systems.
- **Growth trajectory**: 141% headcount growth in the past year; 64 open roles across engineering, regulatory, supply chain, and operations.

## Sources
1. [radiantnuclear.com](https://www.radiantnuclear.com/) – Product details, specs, deployment model
2. [builtin.com](https://builtin.com/company/radiant) – Company overview, perks, culture, tech stack, reviews
3. [linkedin.com](https://www.linkedin.com/company/r-a-d-i-a-n-t) – Funding, headcount, employee growth, locations, key executives
4. [sbir.gov](https://www.sbir.gov/portfolio/1655711) – SBIR awards, Phase II contracts with U.S. Air Force
5. [jobs.ashbyhq.com](https://jobs.ashbyhq.com/radiant-industries) – Current open positions (64+)

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