During June 2025, this developer focused on modernizing the moonbitlang/core repository by delivering targeted API updates and internal refactoring. Using MoonBit and mbt, they removed deprecated usages across core modules, updated function calls, and aligned example syntax with current API patterns. Their work emphasized maintainability by reducing technical debt and ensuring API consistency, which lowers the risk of breaking changes and streamlines onboarding for new contributors. The developer’s approach centered on careful documentation and code review, resulting in a more predictable and stable foundation for future features. This effort improved the long-term evolution and reliability of the core library.