Junnan Wu focused on stability and reliability improvements in low-level systems software, contributing to both the denoland/vhost-device and geerlingguy/linux repositories. In vhost-device, Junnan enhanced the SCMI protocol handler by fixing axis descriptor retrieval, reporting descriptors individually to prevent buffer overflows and correcting descriptor calculations to ensure accurate sensor data, thereby improving system robustness. For geerlingguy/linux, Junnan addressed a use-after-free vulnerability in the Virtio Net driver by reordering the driver shutdown sequence during system suspend, reducing the risk of kernel panics. These contributions leveraged expertise in C, embedded systems, device drivers, and protocol implementation, demonstrating strong problem-solving depth.