Worked on the valkey-io/valkey repository to streamline and simplify the API surface by removing unused callback parameters from several core functions. Focused on maintainability, the approach involved refactoring C code across modules such as src/functions.h/.c, src/db.c, and src/lazyfree.c, making certain internal functions static and explicitly passing NULL for callbacks that were no longer needed. This effort in API design and code refactoring reduced potential misuse and eliminated unnecessary type-cast workarounds, laying the groundwork for safer and more maintainable future development. No user-facing features were introduced, but the changes improved code clarity and consistency throughout the codebase.