Reliability Test Engineer

Company Overview

Mainspring Energy is revolutionizing power generation with the world’s most flexible and adaptable local power generation technology, the Mainspring Linear Generator. Commercial, industrial, and utility leaders are choosing Mainspring over traditional options like engines, turbines, and fuel cells to quickly and reliably deliver local power for EV charging, commercial facilities, data centers, and grid‑scale operations.

The Mainspring Linear Generator is fuel flexible, ramps up and down to meet demand, and utilizes a flameless reaction with near‑zero NOx emissions. Backed by top‑tier investors including Khosla Ventures, Bill Gates, American Electric Power, Lightrock, and General Catalyst, Mainspring designs, manufactures and delivers its products to customers across the U.S. today, and we’re quickly scaling for international expansion.

Inspired by our vision of the affordable, reliable, net‑zero carbon grid, Mainspring is rapidly expanding within the $816B global electricity equipment market, and we’re hiring the best talent to meet growing customer demand around the globe.

We welcome a broad range of backgrounds, experiences, and talents to bring fresh perspectives and ongoing innovation to our customers.

We are looking to build relationships with people who share our values:

Pragmatic Optimism. Building a new category of world‑class power generation requires the optimism of ambition and creativity, balanced with practicality to solve problems efficiently. The challenges that arise are opportunities for growth.

Excellence without Ego. We bring expertise and commitment to creating the best customer experience, from sales to deployment and service, just as we apply deep technical rigor to building and delivering world‑class products. We strive for excellence and behave as leaders with the humility to acknowledge our challenges, both collectively and as individual contributors.

Proactive Collaboration. The integration and cross‑disciplinary nature of Mainspring’s business requires intentionally seeking out others who bring different skills, perspectives, and priorities. Our culture of inclusion and respect extends beyond our team to interactions with our partners and customers.

More information can be found at

• Operate our Linear Generator units

• Perform hands‑on troubleshooting working in close collaboration with other engineering disciplines such as Mechanical, Electrical and Software & Controls.

• Work directly with technicians to coordinate repairs and retrofits

• Review test plans and provide expert guidance on test setup and execution plan

• Setup and maintain instrumentation to collect critical data

• Manage test priorities on a daily basis to meet higher level deadlines with a focus on throughput and maintaining high uptime

• Analyze data, generate reports and communicate results with engineering teams to facilitate learning and design releases

• Develop & improve processes and infrastructure to support testing on our next generation products

• Master’s degree in mechanical engineering, electrical engineering, physics, or equivalent with 3+ years of applicable experience

• Proven experience of conducting experimental hardware projects in industrial environment in the context of product qualification or reliability testing

• Strong organizational and communication skills

• Demonstrated proficiency in complex project management in context of product development

• Proficiency in programming with Python / MATLAB / C++ (at least one)

• Advanced data analysis

• Proficiency with root cause analysis methods

• Proficiency with safety protocols / LOTO procedures for high voltage equipment (and other safety critical systems)

• Proficiency with programming DAQ devices / working with a wide variety of instrumentation/sensors

• Experience communicating with customers/external stakeholders is a plus

$108,000 - $123,600 a year

This position is onsite at our Menlo Park HQ. The salary will be adjusted to reflect local market conditions based on employee location as well as the experience of the employee. Along with the base salary, Mainspring offers pre‑IPO stock options + benefits.

Does your experience not meet all…