Worked on the facebook/zstd repository to improve the robustness of memory allocation in C. Addressed a critical stability issue by introducing a NULL pointer check after the custom allocator invocation within the ZSTD_customCalloc function. This change prevents potential NULL dereference and application crashes when the allocator fails, thereby strengthening error handling in the memory management path. Focused on enhancing product reliability and user safety, the work involved careful analysis of allocation failure scenarios and precise modification of C code. Demonstrated skills in C programming, memory management, and software development, contributing to a more stable and resilient codebase.