Debbie Horsfall developed two core platform features for the flipperdevices/u-boot repository, focusing on the Vexpress64 board. She enabled early entropy provisioning by integrating the DM_RNG virtio RNG driver, allowing the kernel to access secure random data at boot and supporting features like address layout randomization. Additionally, she implemented robust system reset handling by enabling SYSRESET and SYSRESET_PSCI, removing redundant code, and leveraging the sysreset uclass for proper reset management. Working primarily in C, Debbie applied her expertise in driver development, embedded systems, and kernel configuration to improve boot security, reliability, and readiness for capsule-on-disk workflows.