Test Engineer – Nuclear Microreactor (Onsite El Segundo)

Radiant; El Segundo (CA); On-site; USD 106,500 - 146,475; Full time

Benefits offered by this job

Stock options

Medical benefits

One Medical

Dental coverage

Flexible PTO

Lunch provided

Job summary

Radiant, an El Segundo, CA-based startup, is building portable nuclear microreactors. We seek a Test Engineer to drive mission-critical test operations for development, qualification, and acceptance of Kaleidos reactor technology.

You will bridge engineering, operations, and human factors, translating complex hardware and software designs into executable test procedures, while contributing to risk assessment, data review, and hardware performance analysis.

Qualifications

• 2+ years of full-time engineering experience in design, analysis, or testing.
• Bachelor’s degree in mechanical, manufacturing, or related engineering.
• Ability to apply first principles thinking in uncertain or ambiguous situations.
• Background in highly regulated industries (nuclear, aerospace, aviation, maritime).

Responsibilities

• Lead testing as a Test Conductor/Test Director, ensuring procedures align with real-world execution.
• Collaborate with engineers to improve test system interfaces, workflows, and software tools.
• Support testing and iterative improvements of reactor hardware through development, qualification, and acceptance testing.
• Support one-off test campaigns in a fast-paced environment to drive hardware risk reduction.
• Ensure compliance with DOE and NRC standards, maintaining clear procedural documentation.

Skills

Engineering problem-solving

First principles thinking

Regulated industry experience

Project leadership

Thermodynamics fundamentals

Strong communication

Self-driven / flexible mindset

Education

Bachelor’s degree in mechanical/manufacturing or related engineering

Tools

Ion

Epsilon3

NX CAD

Teamcenter

Beckhoff PLC

Job description

Radiant, an El Segundo, CA-based startup, is building portable nuclear microreactors. We seek a Test Engineer to drive mission-critical test operations for development, qualification, and acceptance of Kaleidos reactor technology.

You will bridge engineering, operations, and human factors, translating complex hardware and software designs into executable test procedures, while contributing to risk assessment, data review, and hardware performance analysis.