Stackless Python

Stackless Python is a version of CPython that implements 'microthreads,' allowing for massive concurrency without the overhead of standard OS threads. It is designed for applications that require thousands of simultaneous tasks, such as game servers, high-traffic networking applications, and complex simulations. By removing the reliance on the C call stack, Stackless enables lightweight task switching. While modern Python's asyncio has reduced the need for Stackless in some areas, it remains a powerful tool for specific high-concurrency use cases.