Worked on the PKUHPC/CraneSched repository, focusing on backend reliability and correctness in C++ over a two-month period. Addressed three critical bugs affecting task execution, environment variable handling, and network stability. Improved the assignment of the CRANE_PARTITION environment variable, ensuring default-partition tasks were configured accurately and reducing runtime errors. Enhanced the retrieval of environment variables by querying the task manager, which improved consistency and correctness in task configuration. Strengthened inter-service communication by adding gRPC keepalive channel arguments, increasing connection stability. The work emphasized backend development, bug fixing, and network programming, prioritizing system reliability and risk reduction over new feature delivery.