Worked on the pmndrs/zustand repository to enhance type safety within the Immer middleware, focusing on improving compatibility with sliced stores. Introduced a generic type parameter to the middleware, enabling more robust and flexible type definitions that reduce type-related errors in client code. Developed comprehensive tests to validate typing across different slice types, ensuring correctness and maintainability as the codebase evolves. The work emphasized clarity in type definitions and aimed to streamline the developer experience for large-scale TypeScript applications. Utilized TypeScript and middleware development skills to deliver a targeted feature that strengthens type safety without introducing breaking changes or regressions.