Chenjun developed a D-Bus caller tracing feature for the linuxdeepin/dde-session-shell repository, focusing on improving diagnostics for unexpected screen locks and system shutdowns. Using C++ and system programming techniques, Chenjun extended the D-Bus interface to allow querying the caller’s process ID and recursively tracing parent PIDs, making it possible to identify the originating application behind lock or shutdown events. This enhancement streamlines troubleshooting by reducing the time needed to pinpoint the source of user-facing issues. The work demonstrated a solid grasp of debugging and inter-process communication, delivering a targeted solution that integrates cleanly with existing session management infrastructure.