Senior Manufacturing Engineer

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 Manufacturing Engineer to help transition Kaleidos from a first-of-a-kind reactor build into a repeatable, scalable production system.

With the initial Kaleidos reactor build complete, Radiant is now applying what we learned through design, fabrication, assembly, integration, and test to the next generation of the product. This includes reducing mass and part count, improving manufacturability and assembly, increasing production repeatability, and developing the processes, tooling, equipment, suppliers, and quality controls required to manufacture reactors at  this role, you will work closely with design, quality, test, supply chain, and operations engineers to influence hardware from the earliest stages of design through fabrication and final assembly.

You will own manufacturing processes for critical reactor components, mechanisms, structures, and integrated assemblies, ensuring designs can be built safely, reliably, and repeatedly while meeting demanding performance and quality requirements.

You will be expected to identify manufacturing constraints early, drive DFM and DFA into the product, develop and qualify production processes, and close the loop between engineering intent and what happens on the factory floor. The ideal candidate is equally comfortable reviewing a CAD model with a design engineer, developing a fixture or manufacturing process, troubleshooting a build issue, working with a supplier, and using production data to improve the next iteration of the product.

This is a hands-on engineering role with significant influence over how Kaleidos evolves from a development program into a manufacturable product.

Responsibilities & Duties Own manufacturing and inspection processes for critical Kaleidos components, mechanisms, structures, and assemblies from design release through fabrication, integration, and final acceptance.

Partner closely with design engineers to drive design for manufacturability and assembly (DFM/DFA), influencing hardware to reduce mass, part count, manufacturing complexity, assembly time, and production risk.

Evaluate designs for manufacturability, inspectability, tolerance stack-up, tooling access, assembly sequence, subsystem integration, and final reactor assembly.

Develop, qualify, document, and continuously improve manufacturing processes for complex mechanical hardware and integrated assemblies.

Translate engineering drawings, CAD models, requirements, and specifications into manufacturing plans, work instructions, inspection strategies, tooling requirements, and production controls.

Define fabrication and assembly approaches for new hardware, including process selection, sequencing, make-versus-buy decisions, and inspection methodology.

Design and develop production tooling, fixtures, assembly aids, lifting equipment, and other manufacturing equipment required to safely…