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 highly motivated Senior Civil Engineer to design and develop critical concrete and precast structural systems supporting Radiant's manufacturing and deployment sites. You will solve unique challenges creating efficient, reliable concrete structures capable of surviving extreme thermal and seismic environments while meeting site and program constraints. You will be responsible for trade studies, material selection, detailed structural analysis, assembly, integration, and testing. You will play a critical role enabling the manufacturing, fueling, and safe storage infrastructure that supports Radiant's microreactors.
Responsibilities & Duties:
- Ownership of critical concrete structures such as spent fuel dry cask storage systems, factory and facility foundations, and precast concrete elements supporting manufacturing and site operations.
- Conduct trade studies and develop designs to meet program requirements for static, thermal, and seismic loading conditions.
- Perform detailed structural analysis (reinforced and precast concrete design, static strength, durability) and dynamic analysis (seismic qualification) to determine structural integrity (margins of safety) using both hand calculations and finite element tools.
- Develop and execute construction, fabrication, and test plans for precast and cast-in-place concrete elements.
- Create and manage a Bill-of-Materials (BOM).
- Find and develop suppliers and fabricators for precast concrete components.
- Own subassembly/structure design, fabrication, and test schedules.
- Own risk analysis (FMEA) for concrete structural subsystems.
- Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.
Required Qualifications & Skills:
- Bachelor's degree from an accredited institution in Civil, Structural, or Mechanical Engineering.
- 5+ years of experience designing concrete or reinforced concrete structures.
- 4+ years of experience performing structural analysis using both hand calculations and finite element tools (Abaqus, Ansys, SAP2000, or similar).
Desired Qualifications & Skills:
- Active PE license (not required)
- Experience with reinforced concrete design codes (ACI 318 or similar).
- Experience designing precast concrete systems, including handling, transport, and erection considerations.
- Experience with dry cask storage design or spent nuclear fuel storage systems.
- Experience with seismic design/qualification of concrete structures.
- Experience with nuclear or other critical-facility structural design.
- Experience designing hardware/structures that were fabricated, deployed, and iteratively improved.
- Experience resolving thermal expansion and thermal gradient issues in concrete designs.
- Experience working with interdisciplinary teams (mechanical, civil, geotechnical).
- Solid understanding and application of GD&T and construction tolerancing.
- Proficiency with both "hand calc" analytical methods and higher-fidelity finite element-based analysis methods.
- Ability to derive free-body diagrams for systems with which one was not previously familiar.
- Self-motivated with strong organizational, written, and oral communication skills.
- Experience with using text-based software development 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.
- 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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
Engineering
28 days ago
Senior Thermofluids Systems Engineer, Power Conversion
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.
Radiant is seeking a Senior Thermofluids Systems Engineer, Power Conversion to own system-level thermodynamic modeling of our power conversion architecture. This architecture converts heat from nuclear fission into electricity for the customer. You will define operating points that balance system performance and constraints, deliver clear boundary conditions for the teams building fluid systems and turbomachinery, and serve as the primary technical bridge into control systems engineering & reactor modeling teams. This role is critical to delivering the first new commercial reactor design in over 50 years.
Responsibilities
- Own system-level thermodynamic performance modeling of the power conversion architecture, including design and off-design operating points across startup, shutdown, transients, and off-nominal conditions.
- Develop and maintain interface requirements and boundary conditions (pressures, temperatures, flow rates, control signals) for fluid system components, pressure equipment, turbomachinery, and power electronics.
- Work with engineers owning hardware and subsystems to develop architectural changes accommodating nominal and off-nominal operation, driving trades across performance, cost, weight, schedule, and safety.
- Serve as the primary interface to control systems engineering, providing plant-level dynamic behavior models, operating envelopes, and control-relevant boundary conditions for reactor control scheme development.
- Build and maintain performance models (e.g., MATLAB, Python, Simulink) characterizing fluid system behavior across all operating states.
- Lead root-cause analysis for cycle performance anomalies, correlating test data with system models to inform engineers owning hardware components.
- Perform or review trade studies to optimize cycle and fluid system architecture against program requirements.
- Own system-level risk analysis (FMEA) for fluid subsystems and cycle performance.
- Communicate clearly with both technical and non-technical audiences across multidisciplinary teams.
Required Qualifications
- Bachelor's degree in Mechanical, Aerospace, Chemical, or Systems Engineering from an accredited institution.
- 5+ years of experience in thermodynamic/power cycle modeling, systems engineering, or performance engineering, including requirements development and system-level verification.
- Strong working knowledge of thermodynamics and fluid dynamics as applied to power generation cycle design.
- Proficiency in system modeling tools such as MATLAB, Simulink, or Python for performance and simulation analysis.
- Strong first-principles analytical skills, with the ability to manage competing priorities and communicate program status clearly.
Desired Qualifications
- Experience with fluid system architecture, including piping, compressors, valves, and heat exchangers.
- Experience supporting control scheme development for thermal or power generation plants.
- Familiarity with process piping and pressure vessel codes such as ASME B31.3, BPVC Section VIII, and BPVC Section III.
- Experience with turbomachinery performance modeling or heat rejection system design (e.g., cooling towers, air-cooled condensers).
- Experience supporting hardware build, assembly, and test in a production or development environment.
- Prior experience with FMEA and formal risk management processes.
- Nuclear industry experience is a plus but not required.
Additional Requirements
- Must be willing to work extended hours and weekends as necessary to accomplish our mission.
- Must work 100% on-site 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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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.
THE ROLE
We are looking for a Supply Quality Engineer who builds supplier programs that prevent problems rather than react to them. You will own the development, qualification, and long-term reliability of Radiant's supply base — establishing the processes, standards, and supplier capabilities that ensure the right part arrives to the right standard, every time. While you'll have the technical depth to handle non-conformances and corrective actions when they arise, your primary focus is upstream: strengthening supplier processes, closing capability gaps, and building a supply base that performs without constant intervention.
This is a builder role: the old house is being brought down, and a new foundation is being poured, but we still need to build the structure, apply the finishes, and pass final inspection. You'll own what exists, upgrade aging systems, and create something the industry hasn't seen before.
We're not here to maintain the status quo in nuclear quality — we're here to raise the bar. Radiant is building a supplier reliability program from the ground up with a singular goal: the right part, to the right standard, on time, every time. If you want to do the most meaningful quality work of your career in an industry that hasn't been disrupted in decades, this is that opportunity.
Responsibilities & Duties:
- Own the supplier qualification and onboarding process end-to-end — pre-assessments, capability reviews, audit execution, and formal approval to the Approved Supplier List.
- Own, refine, and expand quality program documentation — including quality clauses, commodity-specific requirements, and the Supplier Quality Manual — building on existing foundations and authoring what doesn't yet exist.
- Develop supplier capability improvement plans — identify process gaps, partner with suppliers to close them, and track progress against defined milestones before problems reach Radiant's dock.
- Own Radiant's procurement assurance and acceptance framework — define how items are accepted across supplier types and quality levels, establish purchase order quality requirements, certifications, material traceability, and compliance documentation, and build toward a graded, systematized model.
- Execute supplier audits and manage supplier performance — audit against Radiant quality program requirements, author findings to closure, and drive structured improvement plans with emphasis on early intervention over lagging indicators.
- Partner cross-functionally with design engineering, manufacturing, and materials teams to translate technical requirements into supplier-facing quality requirements before parts are ordered.
- Process and disposition supplier quality issues when they arise — deviation requests, non-conformance reports, supplier corrective action requests, root cause analysis, and verification of corrective action effectiveness.
Required Qualifications & Skills:
- Bachelor's degree in Engineering, Quality, Materials Science, or a related technical field
- 3–6 years of hands-on experience in supplier quality, supplier development, or supplier reliability engineering in a regulated industry (nuclear, aerospace, defense, or medical device)
- Demonstrated ability to independently process supplier quality transactions: deviation requests, non-conformance reports, supplier corrective action requests, purchase order quality reviews, and cert package review — without step-by-step guidance
- Proven experience owning or drafting quality program documents: quality clauses, supplier requirements, inspection instructions, or equivalent
- Working knowledge of ISO 9001, AS9100, or equivalent quality management systems, including supplier audit methods and corrective action management
Desired Qualifications & Skills:
- Experience in the nuclear industry or direct familiarity with NQA-1, 10 CFR 50 Appendix B, 10 CFR 21, ASME BPVC Section III and/or VIII
- Manufacturing process depth in one or more of the following: machining, welding, casting, forming, special processes, or precision fabrication — sufficient to audit a supplier's process controls and identify gaps
- Certified NQA-1 Lead Auditor, or documented progress toward certification
- Qualified Inspector status (ASME Section III) or working toward it
- Exposure to ISO 17025 accredited laboratories or third-party inspection bodies
- Experience at an early-stage company or program where processes were built or advanced, not inherited
Who You Are:
- You take full ownership of your domain — you identify what needs to be built or improved, write the procedure when one doesn't exist, and drive it without waiting to be asked.
- You solve problems from first principles — when a standard doesn't map cleanly to the situation, you reason from the underlying requirement rather than defaulting to precedent or guesswork.
- Attention to detail is non-negotiable — in a safety-critical, auditable environment, imprecision in a quality record, a clause, or an audit finding has real downstream consequences.
- You hold suppliers — and yourself — to a high standard, and you're energized by preventing failures rather than resolving them — you'd rather fix the supplier's process than write the corrective action.
- You care about the mission: bringing clean, reliable energy to places that need it most, and you understand that quality in this industry is not bureaucratic overhead — it's a safety imperative.
- You thrive in a fast-paced, resource-constrained environment where the work is hard and the stakes are real.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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 Stress Engineer to own and execute structural loads, vibration, and dynamic analyses for complex mechanical systems associated for Kaleidos, the world's first portable microreactor and supporting hardware. You will play a critical role in ensuring structural integrity and survivability across all phases of the product lifecycle, including manufacturing, transportation, handling, deployment, and operational environments.
This role requires a hands-on engineer who is comfortable working in ambiguous, fast-paced environments and collaborating closely with structures, mechanical design, thermal, nuclear, and test teams.
Responsibilities & Duties:
- Develop and own static, dynamic, and transient loads for reactor systems, support structures, and transport configurations.
- Perform structural dynamics analyses, including modal, random vibration, shock, sine vibration, and fatigue assessments.
- Implement explicit dynamics simulations to model nonlinear reactor response under transient seismic and transportation event cases.
- Define and analyze transportation and handling environments, including shock and vibration from road, rail, air, or sea transport.
- Generate load cases and environments to support structural sizing, design margins, and verification plans.
- Conduct finite element analyses (FEA) using tools such as ANSYS, Abaqus, or similar tools.
- Collaborate with design engineers to influence hardware architecture, material selection, and joint design.
- Support test planning and correlation, including shaker tests, modal surveys, and structural verification testing.
- Develop and maintain analysis documentation, reports, and requirements for internal reviews and regulatory interfaces.
- Contribute to failure investigations, root cause analyses, and design improvements
- Help establish best practices for loads, dynamics, and structural verification within a growing engineering organization.
Required Qualifications & Skills:
- Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, Structural Engineering, or a related field.
- 4+ years of professional experience in stress, loads, dynamics, or structural analysis for complex mechanical systems.
- Strong fundamentals in structural mechanics, dynamics, and vibration.
- Experience with finite element modeling and analysis of metallic and composite structures.
- Proficiency with industry-standard FEA tools (e.g., ANSYS, Abaqus, Nastran).
- Familiarity with design allowables, safety factors, and margin-of-safety methodologies.
- Ability to work cross-functionally and communicate analysis results clearly to both technical and non-technical stakeholders.
Desired Qualifications & Skills:
- Experience in aerospace, launch, defense, nuclear, or heavy industrial hardware environments.
- Dynamics modeling software experience (LD-Dyna, Abaqus explicit, or other).
- Background in shock and vibration testing and test-article correlation.
- Knowledge of fatigue, fracture mechanics, and bolted joint analysis.
- Experience defining or interpreting environmental specifications and requirements.
- Master’s degree or PhD in a relevant engineering discipline.
- Familiarity with nuclear, spaceflight, or safety-critical system requirements.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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 with a strong focus on full-stack PCB development, including mixed-signal design, high-speed interfaces, power distribution, and signal integrity, while supporting data acquisition, signal conditioning, estimation, and real-time processing functions critical to reactor control. To lead the electrical architecture for terrestrial reactor control systems, with a long-term path toward space reactor applications. You will serve as the technical authority for custom hardware, owning the design and development of high-reliability, low-noise printed circuit boards - from requirements definition and schematic capture through layout, bring-up, validation, and field deployment
RESPONSIBILITIES AND DUTIES
- Own the design and development of multilayer PCBs for reactor control and instrumentation systems (terrestrial, with future space applications).
- Define the electrical architecture for mixed-signal systems, including power distribution, analog front-ends, and digital control interfaces.
- Design low-noise analog front-end circuits and ensure robust integration with ADC/DAC and digital subsystems.
- Perform schematic capture, component selection, and PCB layout with a focus on signal integrity, power integrity, grounding, and EMI/EMC mitigation.
- Develop and review high-speed and precision layouts (e.g., sensor interfaces, data acquisition paths, communication buses).
- Bring up, debug, and validate hardware, including board-level testing, instrumentation, and root-cause analysis.
- Create and execute hardware validation and qualification test plans for performance, reliability, and environmental conditions.
- Collaborate cross-functionally with firmware, FPGA, DSP, and responsible engineers to ensure seamless hardware/software integration.
REQUIRED QUALIFICATIONS AND SKILLS
- Bachelor’s degree in Electrical Engineering or a related field.
- 5+ years of experience designing custom PCBs, including multilayer and mixed-signal boards.
- Strong experience with schematic capture and PCB layout tools (e.g., Altium, Cadence, or similar).
- Solid understanding of signal integrity, power integrity, grounding strategies, and EMI/EMC mitigation techniques.
- Experience with analog and mixed-signal design, including sensor interfaces, ADC/DAC integration, and low-noise design practices.
- Familiarity with high-speed interfaces (e.g., SPI, I2C, UART, Ethernet) and layout constraints.
- Hands-on experience with board bring-up, debugging, and lab instrumentation (oscilloscopes, spectrum analyzers, VNAs, etc.).
- Ability to work across disciplines and support system integration in a complex engineering environment.
DESIRED QUALIFICATIONS AND SKILLS
- Master’s degree in Electrical Engineering or a related field.
- Experience designing for high-reliability or harsh environments (nuclear, aerospace, defense, or industrial).
- Familiarity with radiation effects and radiation-tolerant electronics design.
- Experience with power electronics or power distribution design.
- Exposure to FPGA or embedded systems to support hardware/software co-design.
- Familiarity with nuclear instrumentation or detector interface electronics.
- Experience with design for manufacturability (DFM), design for test (DFT), and production bring-up.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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 highly motivated Senior Structural Engineer to design and develop critical structures within Kaleidos. You will solve unique challenges creating efficient and reliable structures that facilitate fission while surviving extreme temperature environments and meeting volumetric constraints. You will be responsible for the following: trade studies, material selection, detailed structural analysis, assembly, integration, and testing. You will have an instrumental impact of fueling the first new commercial reactor design in over 50 years by 2026.
Responsibilities & Duties:
Ownership of critical structures such as mass-efficient transportable shielding systems, container system, and high temperature graphite and metallic systems.
Conduct trade studies and develop designs to meet program requirements.
Perform detailed thermomechanical analysis (static strength, durability/fatigue) and dynamic analysis (vibration, shock) to determine structural integrity (margins of safety) using both hand calculations and finite element tools.
Develop and execute manufacturing/assembly instructions and test plans.
Create and manage a Bill-Of-Materials (BOM).
Find and develop suppliers for components.
Own subassembly design, manufacturing, and test schedules.
Own risk analysis (FMEA) for subsystems.
Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.
Required Qualifications & Skills:
Bachelor’s degree from an accredited institution in Mechanical, Aeronautical, Civil or Structural Engineering.
6+ years of experience designing structures.
4+ years of experience performing stress analysis using both hand calculations and finite element tools (Abaqus, Ansys, FEMAP, or similar).
Desired Qualifications & Skills:
Experience with design of multi-component assemblies in CAD (NX or similar).
Experience designing hardware that was manufactured, deployed, and iteratively improved.
Experience resolving thermal expansion issues in designs.
Experience working with interdisciplinary teams.
Solid understanding and application of GD&T.
Proficiency with both “hand calc” analytical methods and higher fidelity finite element-based analysis methods.
Ability to derive free-body diagrams for systems with which one was not previously familiar.
Self-motivated with strong organizational, written, and oral communication skills.
Experience with using text-based software development 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.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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 highly motivated Nuclear Engineer responsible for developing nuclear engineering solutions for our Kaleidos microreactor. This may include nuclear engineering areas such as radiation shielding, criticality safety, accident dose consequence, reactor physics modeling and design, transient analysis, and radiation detection. You will lead and own nuclear engineering initiatives and studies, strategic direction, and work closely with a collaborative nuclear and engineering team in a fast-paced startup environment. The ideal candidate is passionate about advanced reactor design, detail-oriented, effectively communicates, and a tenacity to solve interesting technical challenges.
Responsibilities & Duties :
Ownership of Nuclear design and analysis, examples include:
Shielding: Operational dose and shutdown activation analysis, waste categorization, and alignment of shielding design to customer and regulatory requirements.
Neutronics: Analysis of ex-vessel reactor fluxes and energy deposition, criticality safety, and verification and validation (V&V) of the nuclear toolbox and reactor models.
Accident and Dose Consequence: Radiological dose consequence from different accident scenarios for the Kaleidos demonstration and production units.
Transient Analysis: Run coupled neutronics and thermal calculations to further understanding of the reactor dynamics of the Kaleidos reactor design.
Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.
Other nuclear design and analysis duties as assigned.
Required Qualifications & Skills:
Bachelor’s degree in nuclear engineering or equivalent degree from an accredited institution.
1-2+ years of nuclear engineering industry experience (MS equivalent to 2 yrs).
Experience with radiation transport methods, including with codes such as MCNP/OpenMC/Serpent.
Proficient in at least one of the following programming languages: Python, C++, C#, FORTRAN, or another scientific computing language.
Basic knowledge of thermal hydraulic principles.
Self-motivated with strong organizational, written, and oral communication skills.
Experience working in an engineering organization and developing high-quality work.
Desired Qualifications & Skills
Experience with variance reduction techniques and associated software (Attila4MC and/or ADVANTG), is a plus.
Strong experience with OpenMC, Serpent, MCNP, Attila4MC, MOOSE, RELAP, Pronghorn, GRIFFIN, or other similar nuclear software packages.
Competency in distributed software development processes and high-performance computing environments.
Familiarity with CAD design software (NX, SolidWorks, and/or SpaceClaim), is a plus.
Familiarity with dose consequence methods and software such as MAACS or NRC-RADTRAN.
At least 1 year of software development or scripting experience.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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 a seeking a Nuclear Engineer, Core Physics responsible for designing and implementing nuclear-specific testing operations at our 2026 demonstration. You will be responsible for the design of a large portion of the test campaign, which includes providing analysis to verify that the proposed testing is both safe and meets the test’s objectives. This position will work closely with nuclear engineers to establish test success criteria and systems / operations engineers to implement written procedures.
Responsibilities & Duties:
Collect testing requirements, objectives, and success criteria from nuclear engineers.
Develop procedures that satisfy test requirements within the operational bounds of Kaleidos.
Perform various reactor physics calculations (neutronic and transient analyses) to verify proposed testing sequence addresses all requirements.
Document testing procedures and support operator training and control room GUI development.
Required Qualifications & Skills:
Bachelor’s degree in nuclear engineering or equivalent degree from an accredited institution.
2+ years of experience with reactor operations.
Experience with radiation transport methods, including with codes such as MCNP/OpenMC/Serpent.
Knowledge of thermal hydraulic fundamentals.
Desired Qualifications & Skills:
4+ years of experience with reactor operations.
Direct experience as a reactor operator of an existing nuclear reactor.
Hands-on experience in developing technical procedures, human factors engineering, or operational interface design.
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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
Engineering
33 days ago
Senior Mechanical Engineer (Sheet Metal Structures)
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 highly motivated Senior Mechanical Engineer to design and develop critical structures within Kaleidos. You will solve unique challenges creating efficient and reliable structures that facilitate fission while surviving extreme temperature environments and meeting volumetric constraints. You will be responsible for the following: trade studies, material selection, detailed structural analysis, assembly, integration, and testing. You will have an instrumental impact of fueling the first new commercial reactor design in over 50 years by 2026.
Responsibilities & Duties:
- Ownership of critical structures such as mass-efficient transportable shielding systems, container system, and high temperature graphite and metallic systems.
- Conduct trade studies and develop designs to meet program requirements.
- Perform detailed thermomechanical analysis (static strength, durability/fatigue) and dynamic analysis (vibration, shock) to determine structural integrity (margins of safety) using both hand calculations and finite element tools.
- Develop and execute manufacturing/assembly instructions and test plans.
- Create and manage a Bill-Of-Materials (BOM).
- Find and develop suppliers for components.
- Own subassembly design, manufacturing, and test schedules.
- Own risk analysis (FMEA) for subsystems.
- Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.
Required Qualifications & Skills:
- Bachelor’s degree from an accredited institution in Mechanical, Aeronautical, Civil or Structural Engineering.
- 6+ years of experience designing structures.
- 4+ years of experience performing stress analysis using both hand calculations and finite element tools (Abaqus, Ansys, FEMAP, or similar).
Desired Qualifications & Skills:
- Experience with design of multi-component assemblies in CAD (NX or similar).
- Experience designing hardware that was manufactured, deployed, and iteratively improved.
- Experience resolving thermal expansion issues in designs.
- Experience working with interdisciplinary teams.
- Solid understanding and application of GD&T.
- Proficiency with both “hand calc” analytical methods and higher fidelity finite element-based analysis methods.
- Ability to derive free-body diagrams for systems with which one was not previously familiar.
- Self-motivated with strong organizational, written, and oral communication skills.
- Experience with using text-based software development 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.
- 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.
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.
Listed by Radiant for a position based in the United States. Employers on this board attest they are hiring domestically.
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