Python from the inside out

From processes, threads and coroutines down to the kernel, then inside the CPython interpreter itself.

Series · 2 parts

Part 1 · Oct 16, 2026 · 13 min read

How Python runs concurrent code: from processes, threads and coroutines down to the kernel, and back up to FastAPI

Processes, threads, the GIL, coroutines, the event loop, epoll and FastAPI: what each layer does when a Python server holds thousands of requests at once, with experiments you can run.
Part 2 · Oct 16, 2026 · 16 min read

Inside CPython: everything is an object, from numbers to modules, and what import really does

What an object looks like in memory, how types and functions are objects too, then import step by step: sys.modules, finders, loaders, packages, .pyc files, up to the moment uvicorn loads a FastAPI app.

How Python runs concurrent code: from processes, threads and coroutines down to the kernel, and back up to FastAPI