Cosmopolitan Libc allows you to build programs that run on six operating systems (Linux, Mac, Windows, FreeBSD, NetBSD, OpenBSD). I ported Python 2.7.18 and 3.6.14 to build on Cosmopolitan Libc because I wanted to have the same Python executable and my scripts with me everywhere :) I've updated the blog post for context.

The flask demo is unnaturally slow because my old computer is slow (running python tests in the background). plus I was using `_dummy_thread` Python3.6's pure-python threads implementation.