Developed cross-platform PipeConnection support for inter-process communication in the python/typeshed repository, focusing on enhancing the multiprocessing module’s Listener and Client classes. This work enabled more robust and consistent IPC functionality on non-Windows platforms by aligning type annotations with actual runtime behavior. Leveraging expertise in Python, multiprocessing, and inter-process communication, the developer addressed compatibility gaps that previously limited the use of PipeConnection outside Windows environments. The implementation required careful integration with existing type stubs to ensure accuracy and maintainability. Over the course of the month, the contribution delivered a targeted feature that improved cross-platform development workflows for Python users.