Principal Firmware Engineer
Lunar Energy· Mechanical Or Industrial Engineering· Jul 22, 2026 · 3mo agoPosted 97 days ago
Mountain View, CA
In office
Full-time
Principal
$230K–$260K
12+ years exp
Before you apply
Ghost Signal:
Open since July 22, 2026 — 97 days, and still accepting applications.
Job description
Principal Embedded firmware engineer
As an Principal Embedded Firmware Engineer, you'll play a central role in shaping the intelligence inside our hardware, writing the code that makes our devices perform reliably, efficiently, and safely in homes around the world. You'll work across the full embedded stack, from low-level bootloader to high-level application firmware, in a fast-moving team where your contributions have real and immediate impact.
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 firmware for our hardware devices, including optimisation on the edge.
Design, code, and test sub-systems that provide high-performance functionality on constrained hardware.
Write code across the full embedded stack — from bootloader to high-level application firmware. Develop platform firmware to support components like flash file systems, communication stacks, and build tool management.
Work in a RTOS environment, including porting and maintenance of the RTOS.
Build component firmware that integrates with other parts of the Lunar system.
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.
Support system test, reliability, and manufacturing teams with special firmware features and debugging.
Review performance data from the Lunar system gathered at internal and external test sites.
Desired skills
12+ years of experience developing and architecting software, with exposure to the full lifecycle from prototype to production.
Experience developing C in bare-metal systems and/or RTOS.
Experience implementing power electronics firmware control functionality.
Ability to integrate hardware and software to develop end-to-end solutions.
Comfortable working in a small, fast-moving team where individual initiative and contributions have a big impact.
Able to contribute in a multi-disciplinary team following modern software engineering practices (e.g. Git, continuous integration).
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:
Medical, dental, and vision insurance for employees and dependents
Flexible Paid Time Off plus 10 paid holidays
Tax deferred 401(k) plan
Paid parental leave for all full time employees including 12 weeks paid parental leave for the birthing mother and 6 weeks paid parental leave for the non-birthing parent
Subsidized EV charging and pre-tax commuter benefits
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.
Our Compensation Philosophy: Our goal is to ensure that all Lunar Energy employees are fairly compensated. Please note that the salary range information that follows is a good faith estimate for this position provided pursuant to the Pay Transparency for Pay Equity Act for California applicants. The salary range estimate for this position depending on level of experience is $230,000-$260,000 USD
The actual offer, reflecting the total compensation package & benefits, will be at the company’s sole discretion, and determined by factors including but not limited to years of experience, job level, geographic location, and other relevant business considerations. The company also reserves the right to amend or modify this job description, employee perks, and benefits at any time.
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Benefits
Benefits detected in the listing.
Dental
Vision
401(K)
Paid Time Off
Parental Leave