Snow apparently spends 20% of his time at Microsoft working on CPython. Katriel says she has been able to focus on performance thanks to Microsoft hiring her and working with Van Rossum.

CPython is the basis for other implementations of the language such as Anaconda and Cinder, Facebook's implementation of it, which aims to boost Python performance for sharing photos on Instagram. ...

You’ll not only use CPython headers to describe those rich objects, but you’ll contend with the possible performance issues of using them. The Python project Cython has similar limitations.

Python is powerful, versatile, and programmer-friendly, but it isn’t the fastest programming language around. Some of Python’s speed limitations are due to its default implementation, CPython ...