About Mainspring

Mainspring Energy manufactures and delivers fuel-flexible, low-emissions local power solutions that rapidly add new capacity and deliver reliable, affordable, and sustainable electric power. The company began commercial shipments of its Mainspring Linear Generators in 2020 and today has hundreds of megawatts in advanced development and field operations for leading Fortune 500 companies, data centers, and utilities. Mainspring also partners with global energy leaders including AEP, NextEra Energy Resources, Schneider Electric, and more.

The core values that ground our work, guide our decisions, and connect us together:

• Pragmatic Optimism
• Excellence without Ego
• Proactive Collaboration

Job Overview

Mainspring Energy has fundamentally redefined onsite power generation. Our breakthrough product—the Mainspring Linear Generator (LGen)—is a completely new category of energy technology. Distinct from an engine, turbine, or fuel cell, the LGen directly converts straight-line motion into electricity using a low-temperature, non-combustion thermochemical reaction.

With only two moving parts per core, a frictionless air-bearing system, and zero-flame chemical conversions, we deliver over 46% net AC electrical efficiency. More importantly, it is the world’s only commercially available technology capable of real-time fuel-switching under load, seamlessly transitioning between natural gas, biogas/RNG, propane, hydrogen, and ammonia.

Behind this mechanical simplicity lies an incredibly complex software abstraction layer. To achieve dynamic load-following, sub-millisecond grid synchronization, and real-time thermochemical adaptive fuel mixing, our proprietary controls manage thousands of high-frequency variables simultaneously.

As a Senior Staff Software Test & Automation Engineer, you will architect the core validation and automation frameworks that ensure this distributed energy asset operates with 100% safety and utility-scale reliability. You will own the strategy for testing the intersection of real-time embedded software, predictive control loops, and multi-fuel dynamics.

Responsibilities

• Architect Automation & Test Infrastructure: Design, scale, and maintain custom hardware test beds alongside robust, reusable test automation frameworks, software tools, and continuous integration/continuous deployment (CI/CD) pipelines

• System Validation & Integration: Develop comprehensive test plans, test cases, technical test approaches, and traceability matrices to validate complex hardware/software integrations and resolve system-level bottlenecks 

• Root Cause & Failure Analysis: Lead deep-dive failure analysis, debug and diagnose issues found during testing, and champion risk mitigation strategies to ensure test stability and environmental reliability

• Strategic Coverage: Drive risk-based testing strategies, performing risk analysis to ensure 100% comprehensive test coverage of all critical-path functionalities

• Cross-Functional Collaboration: Partner with development teams and support cross-functional engineering initiatives to diagnose system anomalies and vet new technologies

Qualifications (Must Haves)

• Experience & Education: Bachelor’s degree in Computer Science or a related field with 16+ years of professional experience, or a Master’s degree with 15+ years in an SDET, Embedded Test, or Software Engineering role

• Strategic Automation Leadership: A proven track record of leading complex automation projects from design to implementation, combined with the foundational ability to perform deep-dive manual exploratory testing and technical test case design

• Technical Versatility: Strong hands-on software development experience in Python and C++, with the flexibility to navigate, debug, and contribute to diverse codebases (including Bash scripting) as the project requires

• AI Workflow Ownership: Demonstrated proficiency in leveraging AI coding assistants as a force multiplier for productivity, combined with the professional judgment to challenge, validate, and expand upon AI-generated solutions to ensure system integrity and long-term maintainability

• Domain Expertise: Professional experience testing and validating systems in at least three of the following areas: Cloud computing, embedded systems, networking, IoT with RTOS, controls, simulations (MIL/SIL/PIL), emulators, or complex algorithms

Desirable Qualifications

• DevOps & Infrastructure: Experience working with containerization and orchestration tools such as Docker, Kubernetes, and configuration management via Ansible

• Industry Tooling: High proficiency with common industry test and development workflows like Jira, Xray, GitLab, or equivalent tools

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 of our posted requirements? Studies have shown that some people are less likely to apply to positions unless they meet every listed requirement. At Mainspring, we are committed to building a diverse, inclusive, flexible, and collaborative environment, so if you want to help us transition the world to clean and affordable electricity, and don’t meet all posted requirements for a particular role, we’d still love to hear from you. Mainspring can sometimes be flexible enough to shift responsibilities for the right person, or otherwise identify open or upcoming roles that may better fit your professional background.

In more traditional words, Mainspring Energy, Inc is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.

This compensation and benefits information is based on Mainspring Energy's estimate as of the date of publication and may be modified in the future. We generally do not negotiate on salary once we have made an offer. The level of pay within the range will depend on a variety of job-related factors that may include location, relevant prior experience and/or education, or particular skills and expertise. New hires joining the company tend to be paid within the starting base pay range noted above, with opportunities to increase pay over time based on development of additional skills, competencies, and company-specific knowledge.