On 2018-07-31 12:56, Victor Stinner wrote:

We try to make CPython build as simple as possible. I'm quite sure that Cython rely on the stdlib.

It does rely on modules like "re" and "functools".

Would depending on Cython open a chicken-and-egg issue?

Yes, that's a problem but it's not unsolvable. For example, we could use the PEP 399 pure Python modules for running Cython. Or we could keep certain "core" C modules (which are used by Cython) implemented directly in C. Note that Cython is not all-or-nothing: it is easy to mix pure Python modules, Cython modules and pure C modules. You can also combine pure C code and Cython code in the same module. Anyway, I know that this is probably not going to happen, but I just wanted to bring it up in case people would find it a great idea. But maybe not many CPython core developers actually know and use Cython?

I would be nice to be able to use something to "generate" C extensions, maybe even from pure Python code.

Cython has a "pure Python mode" which does exactly that. There are several ways to include typing information, to ensure that a module remains Python-compatible but can be compiled by Cython in an optimized way. Jeroen.