Staff Firmware Engineer

Lunar Energy is a home energy technology company that designs and sells integrated clean energy systems for residential customers. Its flagship product, the Lunar System, combines solar power generation, battery storage, and smart energy management into a compact, aesthetically designed unit that allows homeowners to produce, store, and use their own clean electricity. The company also offers the Lunar App and Lunar AI to help homeowners monitor and optimize their energy usage, as well as a Virtual Power Plant (VPP) program called Gridshare that enables customers to share stored energy with the broader grid. Lunar Energy's mission centers on making clean energy accessible, affordable, and simple for everyday homeowners, with the broader goal of accelerating the electrification of homes — including solar, EV charging, heating, and cooking. The company has partnered with Octopus Energy to offer innovative battery electricity plans, reflecting its commitment to rethinking how residential energy is produced and consumed. Lunar Energy has raised $232 million in financing to support its growth and expand its installer partner network across the United States. Founded by engineers with backgrounds at Tesla, Lunar Energy differentiates itself through a platform-first approach that goes beyond a standalone battery product, positioning its system as the foundation for whole-home electrification. The company serves both homeowners and a network of certified installer partners, and has received notable press coverage for its role in redefining home energy with smarter, cleaner power solutions.

Staff Firmware Engineer

Embedded/Firmware Engineers at Lunar will be responsible for the full product development lifecycle of our products’ firmware and software, which are important sources of functionality, adaptability, and optimization of our designs. We are looking for people who are passionate about a more sustainable future, and want to make that vision a reality.  An ideal candidate is excited and ready to collaborate closely with a dedicated, cross-functional team to deliver innovative, best-in-class products. Engineers at Lunar are  hands-on and involved in all aspects of the product, and own the design from forming concepts based on first principles to managing high-volume production quality.

Lunar Energy was founded to transition homes to 100% clean energy—making our electricity greener, our air cleaner and our energy more safe, secure and reliable for all. We’re a fast-growing, global company building the world’s best clean energy products to electrify all homes and connect communities to form clean, resilient virtual power plants.

On a given day at Lunar, you’ll likely…

• Develop wireless network communication solutions for high-volume products, ensuring continuous 24/7 reliability
• Design firmware software that runs in our home energy product components: RF communication protocols, mobile app interfaces, system diagnostics and updates.
• Drive design discussions on system architecture to achieve the desired product functionality. 
• Collaborate with the team on design and development, including participating in code reviews. 
• Work collaboratively with other disciplines across the company to continuously refine and improve our understanding of how our products can create the greatest impact, get to market quickly, and operate reliably for our customers

Desired Skills:

• Degree in a computer-engineering related or adjacent field, or demonstrated commensurate ability.
• 5+ years experience delivering firmware for new products as part of a team.
• Proficiency in C, and working familiarity with Python. Rust knowledge is nice to have.
• Experience working with IP stack protocols: Ethernet, WiFi, TCP, UDP, HTTPS, etc
• Working knowledge of Bluetooth/BLE.
• Experience working with WiFi networks and Espressif ecosystem
• Working knowledge of Oscilloscopes, Logic Analyzers and other lab test equipment

Benefits:

We’re dedicated to creating a remarkable employee experience. At Lunar, competitive base pay is one part of our total compensation package. Lunar employees also have the opportunity to become Lunar shareholders by getting equity in a fast-growing company and participating in our employee stock program.

Additional benefits include: 

• Competitive salary and stock options package
• Private Medical Insurance scheme through BUPA (medical history disregarded)
• A wellbeing and lifestyle benefits plan through Medicash
• 5% employer contributions pension matching
• A budget for work related training of £1,000 per financial year and an allowance of 4 training days
• Cycle To Work scheme and Workplace Nursery benefit
• Access to Spill - Mental Health Support platform
• Enhanced Maternity + Paternity Pay
• 25 days annual holiday entitlement + 8 Bank Holidays
• Flexible start and finish times, fully remote working or hybrid depending on preferences

Our DE&I Philosophy: Lunar Energy is an equal opportunity employer. We are committed to attracting, developing and retaining diverse talent by supporting an inclusive workplace. Lunar recruits, hires, trains, promotes, compensates, and administers all personnel actions without regard to race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, disability status or any other status protected by applicable law.