EuroPython 2025

Inside the Black Box: The Anatomy of Virtual Environments
2025-07-16 , North Hall

Virtual environments are a fundamental part of Python development, but to most developers, they’re largely a ‘black box’. In this talk, we’re gonna dissect the code, file structure and utilities that make them up to learn, and not just grok, how venvs actually work.

I'm sure you activate your virtual environment every day, but when was the list time you stopped to think what the process actually does, and what's inside the code that makes the magic work, beyond the abstract idea of the environment isolation? That's what we'll figure out in this talk. We'll learn how Python installs work in modern operating systems (hopefully, the days of xkcd 1987 https://xkcd.com/1987/ are long gone), explore the files and folders inside venvs, examine their purpose, and browse through the venv module source code to understand the CLI tool we use so often.


Expected audience expertise:

Beginner

Daniel is a software engineer with a background in first, local, and then international and VC-backed startups. He's now the lead engineer at Reckon Digital, where he directs and coordinates several projects with clients such as the UN's World Food Programme.