Worked on reliability and maintenance improvements in the zingolabs/zingolib repository, focusing on wallet development and backend systems using Rust. Addressed a bug that preserved the newest wallet checkpoint window across saves, ensuring recent Sapling checkpoints were not lost during reloads and maintaining transaction reliability after chain reorganizations. Refactored the read_shardtree function to enhance code readability and removed an unnecessary constraint, making future maintenance easier. All changes were validated with end-to-end tests and standardized formatting, emphasizing long-term stability. The work demonstrated a methodical approach to backend and blockchain development, prioritizing maintainability and reducing the risk of reorg-related failures.