Worked on stabilizing PPP networking support for embedded deployments in the zephyrproject-rtos/hal_rpi_pico repository by addressing a linker error that occurred when using LWIP with NO_SYS configurations. Implemented a weak sys_jiffies fallback in lwip_nosys.c, ensuring that builds no longer failed due to missing symbol definitions and that PPP connectivity remained reliable without requiring additional user implementation. The solution was scoped to minimize risk, affecting only the relevant source file and PPP integration. Demonstrated expertise in C programming, embedded systems, and networking, with a focus on linker-level debugging and maintaining robust RTOS-based build environments for embedded applications.