Software Engineer Jobs at Mainspring Energy with Visa Sponsorship

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.

Job Overview

At Mainspring Energy, we’re redefining how distributed power systems are designed, built, and operated. As a Staff Embedded Software Engineer, you’ll develop the low-level intelligence that drives our next-generation energy systems—bridging hardware, firmware, and cloud interfaces in an environment where milliseconds and microvolts matter. This is not just another embedded role. You’ll work on complex, multidisciplinary systems—real hardware, real-time constraints, and real-world impact. You’ll be part of a highly collaborative team that values innovation, craftsmanship, and curiosity.

What You’ll Do

- Design and implement embedded software in C, C++, and Python for control, monitoring, and communications across a growing family of sensors, actuators, and controllers
- Architect next-generation embedded platforms, shaping the evolution of our system from the kernel level to high-level application logic
- Invent and refine communication protocols for our custom in-house I/O devices—where reliability and performance are non-negotiable
- Collaborate deeply with Electrical and Controls teams to bring new hardware to life, from early prototypes to production systems
- Lead and mentor other engineers, cultivating a culture of technical excellence and curiosity
- Develop simulation, testing, and CI pipelines, ensuring code quality and rapid iteration in a hardware-centric environment
- Select and integrate compute hardware, balancing real-time performance, scalability, and cost
- Shape our software culture, contributing to best practices, process definition, and architecture decisions that scale with our ambitions

Your First Year

- Week 1: You’ll fix your first issue and review a colleague’s merge request
- Month 1: You’ll deliver your first driver for a new hardware module
- Year 1: You’ll play a key role in designing our next-generation embedded architecture that unlocks future products and features

You’ll Thrive Here If You

- Get excited about bridging firmware and hardware—and aren’t afraid to break out the oscilloscope when debugging gets interesting
- Love building things from scratch: maybe you’ve spun up your own home IoT project or run an LLM on your GPU
- Enjoy trading insights with peers on embedded systems design, and learning as much as you teach
- Appreciate craftsmanship in code—from clean abstractions to optimized interrupt routines
- Don’t mind if something smokes now and then (we’ve all been there)

Qualifications

- 12+ years of experience developing software for embedded or real-time systems, including design, implementation, and testing
- Deep expertise in C/C++, with strong Python proficiency for tooling and automation
- Proven experience with Linux kernel builds, customization, and debugging
- Solid understanding of software architecture and interface design in resource-constrained environments
- Hands-on experience with cross-compilation, build systems, and CI/CD
- Basic familiarity with electrical engineering fundamentals to support system-level debugging
- Experience using Docker for embedded development and deployment workflows
- Passion for engineering excellence and delivering complete, reliable systems on time

Why Mainspring

At Mainspring Energy, you’ll help build the technologies that make clean, reliable power accessible everywhere. You’ll join a team that values bold ideas, technical mastery, and collaboration across disciplines—where every line of code helps advance the future of energy. 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.

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.

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.