About the Role Moonwatt designs and builds battery energy storage systems. We're growing our engineering team to lead the design and development of firmware for our Battery Management System, and the Firmware Engineer will play a central role in architecting, building, and validating the embedded systems that monitor and control battery performance. You will set technical standards for firmware development, mentor future team members, and work closely with hardware engineers as we bring our next generation of products to market. This is a unique opportunity to own firmware architecture from the ground up in a team small enough that you shape the outcome. What You'll Do Lead the full-stack design, development, and optimization of embedded firmware for our Battery Management System, ensuring robust monitoring and control of battery performance (e.g., state-of-charge, state-of-health, thermal management, fault detection, balancing). Architect scalable, modular, and reliable firmware systems for the BMS, defining system-level requirements, communication protocols, and integration with hardware components. Act as the lead engineer for firmware development, mentoring future team members, setting technical standards, and driving best practices in firmware design and implementation. Collaborate with hardware engineers to integrate firmware with battery system components, including microcontrollers, sensors, and communication interfaces. Design and execute comprehensive testing protocols to validate firmware functionality, reliability, and safety in real-world conditions. Diagnose and resolve complex hardware-firmware issues using tools like oscilloscopes, logic analyzers, and debuggers. Create detailed documentation for firmware architecture, code, and testing procedures to ensure scalability and team collaboration. What We're Looking For Experience 3 to 15 years of experience in embedded firmware development, with a focus on designing and implementing firmware for real-time, safety-critical systems. We will tailor the role based on seniority. Proven expertise in designing firmware architectures for complex embedded systems, preferably for industrial-grade systems. Experience with battery management systems is a plus. Hands-on experience integrating firmware with hardware components, preferably in energy storage, automotive, or similar industries, including testing and debugging. Skills Bachelor's or Master's degree in Electrical Engineering, Computer Engineering, Computer Science, or a related field. Expert proficiency in C/C++ for embedded systems programming. Strong experience with microcontrollers (e.g., STM32, PIC, AVR) and real-time operating systems (RTOS). In-depth knowledge of communication protocols (e.g., CAN, Modbus, SPI, I2C, UART). Proficiency with hardware debugging tools (e.g., oscilloscopes, multimeters, JTAG debuggers). Experience with version control systems (e.g., Git) and agile development methodologies. Familiarity with Python or other scripting languages for automation and testing. Preferred Qualifications Experience in utility-scale energy storage or renewable energy systems, or on battery management systems. Knowledge of functional safety standards (e.g., ISO 26262, IEC 61508). Proven leadership and mentorship skills, with the ability to guide technical teams and drive projects to completion. Strong problem-solving skills and ability to work independently in a fast-paced startup environment. Excellent communication and collaboration skills to work effectively with a small, cross-functional team. Passion for clean energy and sustainability.