Avalanche is a Seattle-based start-up developing compact fusion machines for clean, energy-dense power generation at a scale you can hold in your hands. Our unique approach allows us to build, test, break, learn and iterate in days. The modular design is designed to provide power to applications from austere environments to deep sea vehicles and maritime transport to lunar power.

We know we have an incredibly ambitious mission, and that it requires a wide combination of skills, attitude, and grit to make it happen. If you have a passion for abundant energy, and how we can improve life with it, we want to have a chat with you.

Avalanche might be fit for you if: You are self-motivated, energized by problem solving and working closely with hardware. You enjoy hands-on, creative collaboration with a small, tight-knit team you can work with, laugh with, and learn with on a wide variety of topics. You can learn and pivot between priorities when necessary and you can slide the headphones on, focus, and auger deep into a single topic as needed. You thrive in an atmosphere of development, and you are an ardent learner who’s always looking for ways to grow and improve.

About the Role

Avalanche Energy is seeking a Mechanical Engineer to design, build, and maintain the mechanical systems that support our compact fusion devices. You will work directly on vacuum hardware, structural assemblies, thermal management systems, and supporting laboratory infrastructure, contributing to experiments that are designed, built, and iterated rapidly.

This is a deeply hands-on role. You will be responsible for everything from CAD modeling and component selection to fabrication, assembly, testing, and troubleshooting under demanding conditions. The work spans precision vacuum systems, structural design, thermal and high-voltage management, and integration with experimental hardware. You will be working with materials ranging from stainless steels to refractory metals and ceramics. This is not a desk job or a simulation-first role—this is lab-centered engineering focused on getting complex mechanical systems to work, reliably and repeatably.

Responsibilities

Design, build, and maintain mechanical and vacuum systems supporting fusion experiments, diagnostics, and laboratory infrastructure.

Mechanical Engineer

Work alongside physicists and engineers to conceive, implement, and refine mechanical systems for experimental hardware, from initial concept through fabrication, assembly, and iteration.

Specify, procure, fabricate, and test mechanical hardware including vacuum vessels, structural mounts, thermal interfaces, feedthroughs, and precision mechanical assemblies.

Perform hands-on troubleshooting of mechanical and vacuum systems, diagnosing issues related to leaks, thermal performance, structural loading, alignment, and hardware fit-up.

Support experiment operation by setting up, validating, and maintaining mechanical systems, vacuum hardware, and associated diagnostics.

Provide mechanical insight into experimental results, helping interpret hardware performance, system behavior, and failure modes.

Contribute to continuous improvement of lab mechanical practices, documentation, fabrication standards, and build processes.

Required Qualifications

B.S. degree or higher in mechanical engineering, aerospace engineering, or a closely related field.

2-5 years of post-degree experience in hands-on mechanical engineering roles, preferably in a laboratory or experimental hardware environment.

Strong command of mechanical engineering fundamentals, including structural analysis, thermal systems, fluid mechanics, and materials selection.

Proficiency in 3D CAD tools (e.g., SolidWorks, CATIA, or equivalent) for design, assembly modeling, and drawing generation.

Experience designing, assembling, and operating vacuum systems, including familiarity with pumping systems, gauging, and leak checking.

Experience with thermal management design, including heat transfer analysis, cooling system design, and thermal interface materials.