Worked on the protocolbuffers/protobuf repository to improve codebase hygiene and maintainability by refactoring C# code and removing obsolete artifacts. Focused on internal cleanup, this effort involved eliminating the FeatureSetDescriptor.g.cs file and deprecating the canonical serialized defaults, which reduced the maintenance burden and simplified the build process. No user-facing features were introduced, but the changes clarified ownership of descriptor data and lowered the risk of future technical debt. By streamlining generated code and preparing the repository for upcoming refactors, this work enhanced build stability and positioned the codebase for safer, more efficient development in future iterations.