Software Engineer (Backend)

Software Engineer (Backend) Location: Burlingame, CA Department: ESS Engineering Reports to: Senior Manager, Software Engineering Position Type: Full-time About the Company Peak Energy is the first American venture to advance globally proven sodium-ion battery systems as the storage standard for the new era of renewable energy on a resilient grid. Sodium-ion is cheap, readily available, and safe — making it the leading contender in a rapidly evolving market. Our leadership team is powered by decades of expertise in scaling gigawatt-level innovation at world-class companies such as Tesla, Northvolt, Apple, Powin, Enovix, Zipline, Solid Power, SunPower, and Fluence. We are backed by strategic investment and product partners including TDK Ventures, Eclipse Ventures, and GM Ventures. We recently announced America's first sodium-ion grid storage factory in Sacramento with production starting Q1 2027, and over $1B in signed customer commitments including Jupiter Power and Energy Vault. About the Role Peak Energy is looking for a Software Engineer, Backend to help improve and scale the software platform that manages, ingests, processes, and surfaces operational data from our grid-scale battery storage systems. Our platform transforms raw telemetry from batteries deployed in the field into meaningful data and metrics that customers, operators, and engineers rely on every day. As Peak grows from pilot deployments to gigawatt-scale production, this software becomes increasingly critical to our operations. This is a hands-on backend software engineering role focused on application development, API design, data processing, and system integration. You'll build and improve the services that connect our battery systems, manufacturing operations, and cloud applications, ensuring data is processed reliably and accessible across the organization. You'll join a small software team with significant ownership over the systems you build, working closely with ESS Engineering, Manufacturing Engineering, and Product. What You'll Do Design, develop, and maintain backend applications and services that manage, ingest, process, and surface operational data from deployed battery systems. Build and maintain APIs and application interfaces that enable communication between battery systems, cloud services, and internal applications. Develop data processing pipelines that support critical battery performance metrics, including round-trip efficiency, availability, and cycle tracking. Design and optimize database schemas, queries, and data models to support operational applications, reporting, and analytics. Develop software integrations connecting manufacturing systems, physical devices, and cloud applications. Improve the reliability, scalability, and performance of backend services as Peak's deployment footprint grows. Collaborate with hardware, firmware, and systems engineering teams to integrate new functionality and support evolving product requirements. Troubleshoot production issues, improve application observability, and continuously enhance software quality. What You'll Bring (Minimum Qualifications) <li data-leveltext="" data-font="Symbol" data-listid="2" data-list-defn-props="{"335552541":1,"335559685":720,"335559991":360,"469769226":"Sym