codecrafters-io/build-your-own-x

What it does

CodeCrafters' famous tutorial index, founded on Feynman's 'What I cannot create, I do not understand'. It collects step-by-step 'build your own X' tutorial links across ~30 categories: databases, operating systems, Git, Docker, programming languages, neural networks, web browsers and more.

What's inside

Essentially one huge README list organized by 'Build your own X' categories, each entry tagged with its language and link (e.g. write an LLM in Python, a raytracer in C++); no code of its own.

Tech stack

Pure Markdown; the tutorials themselves span C/C++/Python/Go/Rust and more.

Use cases

• Students & career switchers — truly understand databases and OS internals by building them
• Senior engineers — shore up fundamentals before interviews by hand-rolling Git / Docker
• Tech writers — find writing and talk material by category

Why it's trending

Its learn-by-building catalog remains useful because it turns abstract computer-science concepts into concrete implementation projects.

Current chart placements