What is rustc-dev-guide?

The rustc-dev-guide is a collaborative book that explains how the Rust compiler works under the hood. Its main goal is to help new contributors get oriented when they want to help build or improve the compiler, and to serve as a reference for experienced developers who need to understand a specific part of the compiler they haven't touched before. You can read the published guide online, and the repository contains all the source material that goes into it. At its core, the project is a collection of written documentation built using a tool called mdbook, which turns text files into a readable, navigable website. Contributors write explanations about how different pieces of the compiler function and link out to the official reference docs for the compiler's code. The project also uses tools to automatically check that all web links in the guide are valid and to generate tables of contents for longer sections, so everything stays organized and easy to navigate. The people who would use this are developers who want to contribute to the Rust compiler itself, whether they are newcomers trying to find their footing or seasoned compiler engineers exploring an unfamiliar area of the codebase. Notably, the project actively encourages people who don't know how the compiler works to contribute to the guide. If you want to help but don't understand a part of the compiler, the maintainers will pair you with someone who does, and together you figure it out so you can write up what you learned. This means the project isn't just a documentation effort but also a mentorship pipeline for the Rust compiler community. The project is built entirely from plain-text files that get compiled into a static website, making it straightforward for anyone to propose edits or improvements without needing special software. The maintainers are upfront that the guide is useful today but still has a lot of work left to do, and they actively invite contributions through a public issue tracker where you can claim tasks or suggest topics that are missing.