2027 New Graduate - Mechanical Engineer

Radiant industries; El Segundo (CA); On-site; USD 90,000 - 120,000; Full time

Benefits offered by this job

Stock plan

Medical plan

One Medical

Vision plan

Dental plan

Voluntary benefits

Parental leave

Lunch & Snacks

Flexible PTO

HQ near Pacific Ocean

Job summary

Radiant is an El Segundo, CA-based startup creating portable nuclear microreactors. The company seeks graduates to contribute to design, analysis, and testing of the Kaleidos project, taking ownership from concept through build and validation under guidance from senior engineers.

Ideal candidates will have a BS/MS in mechanical or aerospace engineering, strong fundamentals in thermodynamics and dynamics, hands-on project experience, and proficiency with CAD and analysis tools.

Qualifications

• BS or MS in Mechanical or Aerospace Engineering; December 2026 or Spring 2027 graduation is expected.
• Strong foundation in engineering first principles, including thermodynamics, fluid mechanics, statics, dynamics, and strength of materials.
• Hands-on design and build experience via projects, research, labs, or internships.
• Proficiency with engineering tools such as CAD, analysis software, and lab instrumentation.

Responsibilities

• Contribute to the design, analysis, and testing of our microreactor.
• Take ownership of deliverables from concept through build and validation, with guidance from senior engineers.
• Collaborate across disciplines to integrate designs and resolve technical challenges.
• Support system-level testing, troubleshooting, and design iteration to accelerate KDU development.
• Communicate results through design reviews, technical reports, and presentations to peers and leadership.

Skills

Engineering fundamentals

CAD

Analysis software

Lab instrumentation

Education

BS or MS in Mechanical Engineering or Aerospace Engineering

Tools

CAD

Analysis software

Lab instrumentation

Job description

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.

Responsibilities

• Contribute to the design, analysis, and testing of our microreactor.
• Take ownership of deliverables from concept through build and validation, with guidance from senior engineers.
• Collaborate across disciplines to integrate designs and resolve technical challenges.
• Support system-level testing, troubleshooting, and design iteration to accelerate KDU development.
• Communicate results through design reviews, technical reports, and presentations to peers and leadership.

Qualifications

• BS or MS in Mechanical Engineering, Aerospace Engineering, or a related discipline.
• Graduating in December 2026 or Spring 2027
• Strong foundation in engineering first principles, including but not limited to thermodynamics, fluid mechanics, statics, dynamics, and strength of materials.
• Hands-on experience in design and build through projects, research, labs, or internships.
• Proficiency with engineering tools (e.g., CAD, analysis software, lab instrumentation).

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.

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.