Worked on establishing the foundational architecture for a To-Do List Management Program, focusing on early-stage design within the eunbi-kim/24_2_W_SeProj repository. Created an initial system diagram using diagramming tools and XML to document core components and data flows, providing a clear architectural reference for future development. This design artifact aimed to streamline subsequent implementation, support project alignment, and facilitate onboarding for new contributors. No bug fixes were required during this period, as the work centered on planning and documentation. Maintained repository hygiene and comprehensive documentation to ensure efficient collaboration and a solid base for upcoming engineering tasks.