This individual establishes technical direction, makes system-level hardware/software tradeoffs, leads resolution of the most complex cross-functional issues, and ensures the HCU achieves vehicle performance, drivability, efficiency, functional safety, diagnostics, cybersecurity, electrical robustness, thermal performance, electromagnetic compatibility, manufacturability, quality, serviceability, and regulatory objectives. Define scalable HCU hardware and software architecture, including processors, power supplies, I/O, communications and network interfaces, sensing and actuation circuits, application software, basic software interfaces, runnables, scheduling, state management, fault handling, diagnostics, calibration, bootloader, and software update strategies.