Prototype and Test Engineer
Location: Northern Virginia
Overview
The Prototype and Test Engineer is a high-responsibility, hands-on engineering role focused on the design, assembly, and testing of prototype hardware and systems. This position is critical to advancing reactor subsystem validation by converting design concepts into physical test configurations and executing structured test programs. The engineer will support cross-functional teams by ensuring mechanical integrity, test readiness, and traceability of results to design requirements. This role requires a strong understanding of design-for-testability, mechanical integration, and experimental methods in high-consequence environments.
What you Bring
5 - 8 years of relevant experience in mechanical system prototyping, hardware development, and/or system-level testing
Proficiency in 3D CAD tools and technical drawing creation
Hands- on experience with instrumentation and data acquisition tools
Knowledge of thermal-fluid systems, mechanical assembly practices, and basic structural analysis
Demonstrated ability to work in a multidisciplinary, fast-paced development environment
B.S. degree in STEM field
Prototype Design and Integration
Support the design and integration of mechanical and instrumentation components for prototype systems, including thermal loops, test vessels, support structure, etc.
Develop 3D models, fabrication drawings, and bills of material to realize test hardware
Drive design-for-manufacturing and design-for-test outcomes
Interface with vendors and fabricators to support procurement and build activities
Test Planning and Execution
Assist in developing test plans and procedure to validate component and system-level performance
Select and integrate instrumentation, data acquisition systems, and control hardware
Participate in test setup, commissioning, and safe execution of thermal, pressure, or functional tests
Record, analyze, and interpret test data and contribute to technical reports and design updates
Ensure test configuration align with verification objectives and regulatory or safety requirements
Why This Role:
Work directly with team building breakthrough hardware at well-funded, seed-stage hardware startup
Own critical contributions from day one
Join a team that moves fast, thinks big, and builds real things
Competitive salary, benefits, and revenue share when a product realized from your idea gets commercialized. Let us know if you’d like a longer version with compensation, benefits, or more about the company.
Skills Required
- 5-8 years relevant experience in mechanical system prototyping, hardware development, or system-level testing
- Proficiency in 3D CAD tools and technical drawing creation
- Hands-on experience with instrumentation and data acquisition tools
- Knowledge of thermal-fluid systems, mechanical assembly practices, and basic structural analysis
- Demonstrated ability to work in a multidisciplinary, fast-paced development environment
- B.S. degree in a STEM field
What We Do
Mersenne Labs is an advanced energy company dedicated to re-engineering the world's energy systems. The company is designing compact, long-duration nuclear generators and the world's first 'forever batteries' to facilitate a mobile, grid-less world. Their mission is to provide radically autonomous and resilient energy solutions that ensure power is accessible anywhere and anytime, moving beyond traditional grid dependencies.
