Senior Software Engineer – Site Controller, Energy Storage 

We are at the precipice of a global energy transition. At Redwood Materials, we are moving beyond battery recycling to build the most advanced, circular energy ecosystem on the planet. Our goal is to move the industry away from static, hardware-heavy infrastructure toward agile, software-controlled energy assets. 

The Site Controller is the "Central Nervous System" of our modular Battery Energy Storage Systems (BESS). It is the platform that allows us to harmonize new and repurposed batteries into a single, high-performance energy asset. We are looking for engineers to build the digital backbone that finally makes renewable energy baseload-ready and turns the grid into a truly digital, responsive network. As a Site Controller Software Engineer, you will be responsible for the high-level orchestration of our grid-scale storage sites. Operating at the "System Coordination" layer, you will design and implement the mission-critical logic that dictates how GWh-scale sites interact with the utility, industrial assets, and the Redwood Cloud. You will build the scalable, resilient software platform that makes our proprietary "Pack Manager" technology possible. 

Responsibilities will include:

• Distributed System Architecture: Design and implement a scalable, resilient software architecture for the Site Controller, ensuring it can coordinate thousands of distributed microcontrollers with zero downtime. 
• Tiered Control Logic: Lead the development of multi-rate control systems, balancing high-level site coordination with real-time grid execution. You will collaborate with simulation and controls teams to optimize state-of-charge and battery longevity at the site coordination layer, while leading the integration of high-speed closed-loop controls to ensure sub-cycle grid synchronization and precise command execution. 
• System Resilience & Fault Handling: Architect robust fault-management frameworks, designing the state machines responsible for autonomous error recovery and failsafe modes. 
• Deterministic Networking: Architect the physical and real-time networking layers. You will define the communication interfaces and network protocols that ensure low-latency, reliable data flow between the site controller, local assets, and upstream telemetry. 
• Hardware Abstraction & Integration: Design and define the critical software interfaces that enable our "Pack Manager" to serve as a universal translator. You will architect the communication layers to ensure high-availability and resilient data exchange between the centralized site controller and a heterogeneous fleet of downstream microcontrollers.  
• Testable Software Excellence: Design and implement highly modular, testable software. You are responsible for ensuring that all site controller logic is built with automated unit and integration testing in mind, providing a robust foundation for system-wide validation. 
• System Diagnostics: Familiarity with distributed logging tools and optimizing telemetry data flows for real-time system health and performance tracking. 

Desired Qualifications: 

• Background: A BS or MS in Computer Science or Electrical Engineering, combined with 2+ years of professional experience developing application-layer software for hardware-constrained systems. 
• Modern Toolchain: Proficiency in Rust and Python. You understand when to leverage Rust’s safety and performance for site orchestration and how to utilize Python for rapid tooling and simulation. 
• Industrial Networking: Deep familiarity with industrial communication protocols (Modbus TCP and CAN). Experience with DNP3 or IEC 61850 is a significant plus. 
• System Administration: Strong experience with Linux system administration and modern containerization technologies (Docker, Kubernetes) for edge computing. 
• Fleet Orchestration: Experience implementing and managing high-availability Firmware Over-the-Air (OTA) pipelines, ensuring secure and reliable updates from the cloud through to downstream controllers. 
• Data Lifecycle: Experience with time-series databases and data visualization tools for monitoring system health and energy flows. 
• Hardware Integration: Proven track record of integrating vendor-off-the-shelf (VOTS) components—such as PV systems, industrial inverters, fire safety systems, and HVAC controllers—into a unified software platform.