Worked across the dotnet/diagnostics, dotnet/runtime, and microsoft/perfview repositories to deliver cross-platform diagnostic tooling improvements and enhanced test robustness. Focused on expanding test coverage to macOS and Linux, improving memory analysis through new sorting options, and refining error handling for IL stubs and debugger stack dumps. Leveraged C#, C++, and Python to implement features such as symbol server enhancements, alternate signal stack support, and module name display cleanup. Addressed crash regressions and improved reliability in diagnostic tools by introducing targeted bug fixes and code refactoring, resulting in more maintainable codebases and streamlined developer workflows across multiple environments.