Senior Nuclear Engineer

Senior Nuclear EngineerJoin Radiant Industries as a Senior Nuclear Engineer! In this pivotal role, you will take the lead on modeling techniques and reactor physics calculations that drive neutronics parameters such as reactivity, kinetics parameters, and energy deposition distributions. These calculations are integral to our innovative Digital Twin simulati…

Lead Nuclear EngineerRadiant Industries is on the lookout for a dynamic and technically proficient leader to head our nuclear design and analysis team, specializing in core physics, shielding, instrumentation & controls, and reactor operations. In this pivotal role, you will guide a talented team through the intricate design, development, and testing phases of the innovative Kaleidos microreactor project. You will be responsible for managing schedules, budgets, hiring, and the successful execution of nuclear-related objectives, with a strong emphasis on safety, reliability, portability, and performance. The ideal candidate thrives in interdisciplinary settings, collaborates effectively with engineers and leadership, possesses a deep understanding of engineering principles, excels in creative problem-solving, and is passionate about mentoring and inspiring engineers to achieve their best work. Join us in our mission to bring the first portable nuclear microreactor to market.Key Responsibilities:Lead a multidisciplinary team of nuclear engineers focused on safety analyses, core performance, shielding—including operational dose, activation, shutdown dose—instrumentation & controls, operations, and thermal-hydraulics.Recruit, mentor, and develop a high-performing team of nuclear engineers.Oversee nuclear engineering projects from inception to completion, including requirements gathering, iterative design, simulation pipeline development, and regulatory deliverables.Collaborate with the regulatory team to ensure compliance with nuclear industry standards and requirements.Provide mentorship to engineers through constructive feedback and coaching.

Radiant Industries is seeking a talented Nuclear Engineer specializing in Core Physics to join our dynamic team. In this pivotal role, you will be responsible for the design and execution of nuclear-specific testing operations for our upcoming 2026 demonstration. Your expertise will be crucial in developing a substantial portion of our test campaign, ensuring that all proposed testing is not only safe but also aligns with the objectives set forth. You will collaborate closely with fellow nuclear engineers to establish success criteria and work alongside systems and operations engineers to implement comprehensive written procedures.

About Radiant IndustriesRadiant Industries, based in El Segundo, California, is a pioneering startup dedicated to revolutionizing the energy sector with the world's first mass-produced, portable nuclear microreactors. Our flagship reactor, Kaleidos, is a groundbreaking 1-megawatt microreactor designed for mobility and operational efficiency, capable of running for up to five years without the need for refueling. This innovative portable nuclear power solution is set to replace conventional diesel generators, providing essential energy support for hospitals, data centers, remote locations, and military installations. With a unique focus on modern software engineering, Radiant is committed to delivering safe, factory-built microreactors using proven materials. Founded in 2020, we are on a path to test our first reactor at the Idaho National Laboratory next year, with customer deliveries commencing in 2028.About the RoleWe are looking for a skilled Senior Electrical Engineer to lead the design and implementation of electrical control and measurement systems for our microreactor projects. The successful candidate will take ownership of designs from requirements capture to operational deployment. You will be involved in a variety of tasks ranging from circuit board design to integration with fault-tolerant, commercially available hardware. This role will require close collaboration with cross-disciplinary teams focused on the nuclear reactor core, fluid heat transfer systems, and structural components.Key Responsibilities:Collaborate with multidisciplinary teams to design, implement, and test electrical control systems for microreactors.Create and develop industrial-grade electrical control hardware, including schematics, wiring diagrams, harnessing, and integration assemblies.Lead the design of fault-tolerant and safety-critical electrical systems, prioritizing reliability, maintainability, and compliance with regulations.Develop and review electrical interface designs connecting control systems, power equipment, and instrumentation.Ensure compliance of designs with relevant electrical codes and safety standards, including NFPA and NEC.Conduct SCCR and Arc Flash calculations.Qualifications:Bachelor’s degree in Electrical Engineering or a related field.A minimum of 5 years of experience in designing electrical hardware.Proven expertise in electrical control systems and safety-critical applications.Strong understanding of industry standards and codes related to electrical design.Excellent problem-solving skills and a collaborative mindset.

Nuclear EngineerJoin Radiant Industries, a pioneering leader in advanced nuclear technology, as a Nuclear Engineer. You will play a crucial role in shaping the future of our Kaleidos microreactor. Your responsibilities will encompass a variety of nuclear engineering disciplines including radiation shielding, criticality safety, accident dose consequence assessment, reactor physics modeling, transient analysis, and radiation detection. Collaborating with a dynamic team in a startup atmosphere, you will spearhead nuclear engineering projects, set strategic directions, and tackle complex technical challenges. The ideal candidate is not only detail-oriented but also possesses a profound passion for advanced reactor design and exhibits exemplary communication skills.Key Responsibilities:Lead nuclear design and analysis initiatives, including:Shielding: Conduct operational dose and shutdown activation analysis, categorize waste, and ensure compliance with customer and regulatory shielding requirements.Neutronics: Perform analysis of reactor fluxes and energy deposition, ensure criticality safety, and validate nuclear models.Accident and Dose Consequence: Assess radiological dose consequences for diverse accident scenarios related to the Kaleidos units.Transient Analysis: Execute coupled neutronics and thermal calculations to deepen understanding of reactor dynamics.Gather requirements and provide constructive feedback to engineers across various domains through effective communication.Undertake additional nuclear design and analysis tasks as assigned.Qualifications & Skills:Bachelor’s degree in Nuclear Engineering or a related field from an accredited institution.1-2+ years of relevant industry experience (a Master’s degree equates to 2 years).Proficiency in radiation transport methods with experience in MCNP/OpenMC/Serpent codes.Skilled in at least one programming language, such as Python, C++, C#, FORTRAN, or other scientific computing languages.Basic understanding of thermal hydraulics principles.Self-motivated with robust organizational, written, and oral communication skills.

Senior Materials Engineer (Metallurgy)Join Radiant Industries as a dynamic Senior Materials Engineer, where you'll be responsible for the testing and qualification of materials, particularly metals, for our innovative Kaleidos 1MW nuclear microreactor. We’re looking for an individual who takes pride in their work, is highly skilled in materials selection, testing, and analysis, and thrives in a fast-paced, collaborative environment. You will play a crucial role in ushering in the era of the world's first mass-produced, rapidly-deployable nuclear reactor.Responsibilities & DutiesPlan and execute comprehensive materials testing to derive essential material properties for informed design decisions.Spearhead the qualification of all metallic components utilized in the design of the Kaleidos reactor.Conduct rapid prototypic testing to mitigate risks associated with design and integration.Collaborate closely with the manufacturing team to develop and validate application-specific manufacturing processes including welding, brazing, coating, casting, and heat treatments.Provide expert advice on materials selection for various components within the Kaleidos project.Identify and manage equipment necessary for materials characterization and testing.Assess and ensure the quality and accuracy of material property data for our materials database.Define and enhance manufacturing processes to achieve the desired material properties.Required Qualifications & SkillsBachelor’s degree from an accredited institution in Materials Science and Engineering, or Mechanical, Aeronautical, Nuclear, or Chemical Engineering with a focus on materials science.5+ years of experience in the development, testing, and analysis of materials for challenging load scenarios and environments.Desired Qualifications & SkillsMaster’s or PhD degree in a related field is preferred.

Senior Mechanisms EngineerRadiant Industries is on the lookout for a dynamic and experienced Senior Mechanisms Engineer to spearhead the design and development of essential mechanisms within the innovative Kaleidos project. In this role, you will tackle unique engineering challenges to create efficient and dependable mechanisms that govern reactivity and activate critical safety features. Your responsibilities will encompass trade studies, material selection, in-depth structural analysis, assembly, integration, and rigorous testing. Your contributions will be vital in propelling the introduction of the first new commercial reactor design in over five decades by the year 2026.Key Responsibilities:Lead the design and development of crucial mechanisms such as control blade actuators and air jacket valves.Conduct comprehensive trade studies and formulate designs that align with program requirements.Execute detailed thermomechanical analysis (including static strength and durability/fatigue) and kinematic analysis to assess structural integrity and performance margins using both hand calculations and finite element analysis tools.Develop and implement manufacturing and assembly instructions along with test plans.Create and oversee a Bill of Materials (BOM).Identify and cultivate relationships with suppliers for necessary components.Manage schedules for subassembly design, manufacturing, and testing.Conduct risk analysis (FMEA) for subsystems.Gather requirements and provide insights to engineers across other functional areas through effective communication.Qualifications:Bachelor's degree in Mechanical or Aeronautical Engineering from an accredited institution.A minimum of 4 years of experience in mechanism design.Over 4 years of experience conducting stress analysis utilizing both hand calculations and finite element tools (such as Abaqus, Ansys, FEMAP, or equivalent).Desired Skills:Proficient in the design of multi-component assemblies using CAD software (NX or similar).Experience in designing hardware that underwent manufacturing, deployment, and iterative improvements.Familiarity with pneumatic system design.Knowledge in integrating electromechanical components such as motors or encoders.

Senior Mechanical Engineer - Fluid SystemsRadiant Industries is on the lookout for an enthusiastic and experienced Senior Mechanical Engineer specializing in Fluid Systems. This pivotal role involves overseeing the design and development of critical Kaleidos fluid systems, guiding projects from initial design to production. These systems are essential for converting reactor core heat into electrical power.As a key member of our engineering team, you'll engage in trade studies, component selection, thermal hydraulic analysis, piping design, vendor evaluation, assembly, and rigorous testing. Your contributions will play a vital role in launching the first new commercial reactor design in over 50 years by 2026.Responsibilities:Lead the engineering process for fluid systems and components, including compressors, valves, and heat exchangers.Conduct complex thermal and fluid analyses to inform design choices, validate system performance, and maintain structural integrity using hand calculations and finite element analysis tools.Perform trade studies to enhance system performance and fulfill program requirements.Create and implement manufacturing and assembly instructions along with test plans.Manage and maintain a comprehensive Bill of Materials (BOM).Identify and cultivate relationships with suppliers for all components.Oversee the design, manufacturing, and testing schedules for subassemblies.Conduct risk analysis (FMEA) for subsystems.Gather requirements and provide guidance and constructive feedback to engineers across various disciplines.Qualifications:Bachelor’s degree in Mechanical, Materials, Aeronautical, Civil, or Structural Engineering from an accredited institution.Proven experience in fluid system architecture design.A minimum of 4 years of experience in designing, building, and testing fluid systems.In-depth knowledge of fluid dynamics and thermodynamics.Solid understanding of heat exchanger design and analysis techniques.

Senior Motor Design EngineerJoin Radiant Industries as a Senior Motor Design Engineer, where you will play a pivotal role in designing and developing an advanced alternator for our nuclear-powered high-speed generator. This position entails the design of active components as well as conducting structural and thermal analyses of high-speed generators. You will work collaboratively with cross-functional engineering teams and closely engage with the Power Conversion and Electrical Systems team responsible for efficiently converting mechanical energy into electrical energy, ensuring safety and reliability for our clients. As the ideal candidate, you will take ownership of the active part design for generators, and will also be responsible for conducting simulations, performing analysis, and selecting components. Your contributions will directly impact the commercialization of groundbreaking mass-produced nuclear reactors, delivering clean energy to remote areas and critical infrastructure.

About RadiantRadiant, located in El Segundo, CA, is an innovative startup pioneering the development of the world's first mass-produced, portable nuclear microreactors. Our flagship reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor designed for mobility and extended operation, capable of providing power for up to five years without refueling. This revolutionary approach to portable nuclear energy aims to replace traditional diesel generators, delivering essential support for hospitals, data centers, remote locations, and military installations. Founded in 2020, Radiant is poised to test its inaugural reactor at the Idaho National Laboratory in the coming year, with initial customer deployments anticipated to begin in 2028.Position OverviewRadiant is searching for a Senior Advanced Controls Systems Engineer to take the lead in designing, implementing, and validating autonomous control systems for our nuclear microreactors. You will manage the entire control system development process—from defining requirements to operational deployment. Responsibilities include algorithm development, modeling and simulation, embedded implementation, and system validation.This role involves the design and integration of tightly coupled control functions that encompass reactivity control, primary loop mass flow, alternator/generator speed, and coordination across multiple reactors within microgrids. The ideal candidate will possess experience working in regulatory environments, developing autonomous and adaptive control strategies, and conducting system-level analyses of nonlinear, coupled dynamic systems. Close collaboration with multidisciplinary engineering teams focused on hardware, software, and system integration is essential.

About RadiantRadiant Industries, based in El Segundo, CA, is a pioneering startup dedicated to revolutionizing energy solutions through the development of the world's first mass-produced, portable nuclear microreactors. Our flagship reactor, Kaleidos, is a state-of-the-art 1-megawatt, fail-safe microreactor designed for transportability, capable of delivering power for up to five years without refueling. This innovative portable nuclear power source is set to replace conventional diesel generators and provide essential support for hospitals, data centers, remote locations, and military installations. By harnessing modern software engineering, Radiant is committed to rapidly delivering safe, factory-built microreactors using established, high-quality materials. Since our founding in 2020, we are on pace to test our inaugural reactor at the Idaho National Laboratory this summer, with initial customer deliveries anticipated in 2028.About the RoleWe are in search of a Senior Electrical Engineer specializing in PCB design to spearhead the electrical architecture for terrestrial reactor control systems, with aspirations for future applications in space. In this pivotal role, you will act as the technical authority for custom hardware, overseeing the design and development of high-reliability, low-noise printed circuit boards. Your responsibilities will encompass everything from defining requirements and schematic capture to layout, bring-up, validation, and field deployment.This position emphasizes comprehensive PCB development, including mixed-signal design, high-speed interfaces, power distribution, and signal integrity, while also supporting functions crucial for reactor control such as data acquisition, signal conditioning, estimation, and real-time processing.

Senior Structures EngineerRadiant Industries is on the lookout for a dynamic and innovative Senior Structures Engineer to lead the design and development of essential structures within the Kaleidos project. In this role, you will tackle unique engineering challenges, crafting efficient and robust structures that endure extreme temperatures and satisfy volumetric constraints. Your expertise will play a crucial role in advancing the first new commercial reactor design in over 50 years, set to launch by 2026.Key Responsibilities:Lead the design of critical structures, including mass-efficient transportable shielding systems, container systems, and high-temperature graphite and metallic systems.Conduct thorough trade studies and develop innovative designs to meet program specifications.Perform detailed thermomechanical (static strength, durability/fatigue) and dynamic analyses (vibration, shock) to ensure structural integrity, utilizing both manual calculations and finite element analysis tools.Create and implement manufacturing and assembly instructions, along with comprehensive test plans.Manage a Bill of Materials (BOM) and collaborate with suppliers for component development.Oversee subassembly design, manufacturing, and testing schedules.Conduct risk analysis (FMEA) for subsystems.Gather requirements and provide constructive guidance to engineers across different functional areas through effective communication.

Radiant Industries is hiring a Senior Engineering Technician specializing in Welding & Fabrication at its El Segundo, CA site. This technician partners with the Lead Welding Engineer and plays a central role in advancing nuclear reactor technology. The position blends hands-on welding and fabrication with a strong focus on quality assurance and production support. Main responsibilities Develop, implement, and maintain Welding Procedure Specifications (WPS), Procedure Qualification Records (PQRs), and Welder Performance Qualifications (WPQs) for both structural and pressure vessel welds. Interpret engineering drawings, CAD models, and technical specifications to plan and carry out welding and fabrication tasks. Collaborate with production and engineering teams to organize welding and fabrication operations from raw materials through final assembly. Design, build, and refine weld tooling, fixtures, and prototype assemblies to support manufacturing and product development. Deliver hands-on welding training to technicians, ensuring techniques and standards meet requirements. Perform precision fabrication, including cutting, forming, fit-up, and assembly of components and subassemblies. Lead welding and fabrication projects, ensuring all processes and inspections meet regulatory standards. Audit welding processes performed by suppliers to confirm quality and compliance. Identify and procure new equipment to expand in-house welding capabilities. Oversee procurement of consumables, tooling, and materials for welding operations. Support rapid prototyping and iterative development, working with engineering to improve designs for manufacturability. Work environment This position operates within a collaborative startup culture that values adaptability and practical problem-solving. The Senior Engineering Technician in Welding & Fabrication will influence both daily operations and long-term product development at Radiant Industries.

Radiant Industries, based in El Segundo, CA, develops portable nuclear microreactors. The company’s flagship product, Kaleidos, is a 1-megawatt reactor built for safe transport and designed to run for up to five years without refueling. These microreactors are intended to replace diesel generators and provide reliable power for critical infrastructure, including hospitals, data centers, remote locations, and military bases. Radiant uses established materials and advanced software to produce factory-built reactors. Founded in 2020, the company expects to test its first reactor at Idaho National Laboratory this summer, with customer deliveries planned for 2028. Role overview The Senior Software Engineer in Simulation Technologies will develop and maintain software systems supporting Radiant’s reactor simulation and Digital Twin initiatives. This role centers on designing the architecture, tools, and infrastructure that allow simulation engineers to model, test, and validate reactor systems. The work is closely tied to Radiant’s progress toward commercial deployment.

About Radiant IndustriesRadiant Industries is an innovative startup headquartered in El Segundo, California, pioneering the development of the world’s first mass-produced, portable nuclear microreactors. Our inaugural reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor designed for transportation to any location requiring power, capable of operating for up to 5 years without refueling. This cutting-edge technology offers a sustainable alternative to conventional diesel generators, providing essential power support for critical infrastructures such as hospitals, data centers, remote sites, and military bases. Since our inception in 2020, we have adopted a unique approach that combines advanced software engineering with proven materials to safely deliver factory-built microreactors. We are set to commence testing our first reactor at the Idaho National Laboratory next year, with initial customer deliveries projected to begin in 2028.Position OverviewWe are on the lookout for a motivated Senior FPGA Engineer to join our Embedded Systems team. In this role, you will play a crucial part in the design, development, and validation of FPGAs utilized in the reactor's instrumentation and control systems, focusing on safety-critical applications, sensor and actuator management, and communication systems. Collaboration with hardware engineers, embedded software engineers, and test engineers will be essential to create integrated designs that fulfill the operational requirements for monitoring and controlling fission reactors. Your contributions will be pivotal in testing our first commercial reactor design in over half a century.This position is full-time and based onsite in El Segundo, California.

Senior Engineering TechnicianJoin Radiant Industries as a Senior Engineering Technician and leverage your diverse skill set in the fabrication and assembly of our cutting-edge microreactor unit. As a vital member of our team, you will play a key role in developing both large and small-scale test rigs, crafting prototype parts and tooling, and managing material handling. With significant autonomy, you will help establish and maintain our prototype shop at our new headquarters in El Segundo, California, utilizing your expertise in machining, welding, metal forming, electrical work, and plumbing. Your contributions will be instrumental in achieving the successful fueling of a groundbreaking reactor design by 2026.

Role overview Radiant Industries is hiring a Principal Turbomachinery Engineer to act as the Responsible Engineer for advanced turbomachinery within a nuclear-driven power generation system. The focus is on the mechanical design, reliability, and performance of the main rotating assembly in a 1MW closed-loop Brayton cycle. This position requires deep technical ownership of complex, high-speed rotating equipment. What you will do Lead the mechanical architecture for high-speed rotating equipment that operates under extreme temperatures, pressures, and rotational speeds. Guide technical work in rotor dynamics, structural integrity, bearings, seals, and system integration. Collaborate with electrical, thermal, and manufacturing teams to ensure integration across disciplines. Maintain end-to-end responsibility from concept through production, emphasizing technical rigor and sound engineering judgment. Requirements Extensive experience designing and analyzing turbomachinery, with a focus on high-speed rotating hardware. Strong knowledge of rotor dynamics, structural assessment, bearing and seal selection, and system-level integration. Hands-on approach with a track record of delivering production-ready hardware. Ability to work effectively with specialists in electrical, thermal, and manufacturing engineering. Location This position is based in El Segundo, CA.

Radiant Industries is on the lookout for a Lead Electrical Motor Design Engineer to spearhead the architecture, technical direction, and implementation of high-speed alternators and primary loop motors for our cutting-edge nuclear-driven power generation systems. This pivotal role will oversee the electric machine design function that is essential for the commercialization of the world's first mass-produced nuclear reactors.In this position, you will establish a technical vision for motor design while steering efforts in structural, thermal, and system integration. As a player-coach, you will actively engage in design work while mentoring a team of engineers to ensure the delivery of safe, reliable, and production-ready generator systems.This hands-on technical leadership position comes with substantial cross-functional impact.

About Radiant IndustriesRadiant Industries, headquartered in El Segundo, CA, is pioneering the development of the world’s first mass-produced portable nuclear microreactors. Our flagship reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor designed for mobility, capable of providing power for up to five years without the need for refueling. This innovative technology serves as a sustainable alternative to diesel generators, delivering essential power to hospitals, data centers, remote sites, and military bases. Leveraging modern software engineering and advanced materials, we aim to revolutionize nuclear energy. Founded in 2020, we are poised to test our inaugural reactor at the Idaho National Laboratory in the coming year, with commercial deployments targeted for 2028.About the RoleWe are looking for a dynamic and driven early-career Mechanical Engineer to join our team and contribute to the design and integration of electrical systems within our innovative projects. In this role, you will collaborate with seasoned mechanical and electrical engineers to tackle complex challenges related to packaging, thermal management, structural design, and overall system integration for cutting-edge hardware. This position offers a unique opportunity for hands-on experience throughout the entire hardware development process, from CAD design and analysis to testing and validation, all while supporting our mission to successfully launch the first commercial nuclear reactor in over five decades by 2026.Responsibilities & DutiesContribute to the mechanical design and oversight of electrical components and subsystems, including:Designing mechanical assemblies for electrical components such as control panels, enclosures, brackets, mounts, and supports.Routing and securing cables and wiring harnesses, ensuring strain relief, compliance with bend radius, and serviceability.Integrating sensors, actuators, connectors, and electrical hardware within limited spaces.Creating 3D CAD models and 2D drawings using Siemens NX, including tolerance stack-ups and GD&T fundamentals.Conducting initial load calculations (static, shock, vibration) to guide structural design.Performing thermal analyses and heat transfer evaluations for electrical components and assemblies.Assisting in the selection of suitable materials, fasteners, and finishes based on electrical, thermal, and environmental considerations.

Join Our Team as a Reactor Operations EngineerRadiant Industries is on the lookout for a skilled Reactor Operations Engineer to develop and implement essential procedures for our innovative nuclear microreactor technology. This position presents an extraordinary chance to merge engineering, operations, and human factors in a highly technical and regulated setting. You will work alongside a diverse team to transform intricate hardware and software designs into clear, actionable procedures that comply with DOE and NRC standards. Your efforts will empower Reactor Operators (ROs) and Senior Reactor Operators (SROs) to efficiently and safely conduct testing, commissioning, and operational activities.This role transcends traditional systems engineering; you'll also gain practical experience as a Reactor Operator (RO), directly shaping the development of operational software, procedures, and digital twin simulations. Your contributions will play a vital role in enhancing operator efficiency, safety, and the real-world execution of our state-of-the-art microreactors.