Crystal Book

Welcome to the documentation for the Crystal language.

Crystal is a language for humans and computers. These materials help humans understand the language and its ecosystem.

Learning Materials

These instructions and courses help you get to know the language and how to use it.

Install Crystal and get it running.

Introductory courses for beginners and advanced learners.

Detailed examples for practical applications.

The core documentation of the Crystal language, standard library, and tooling.

Specification of the language.

Documentation of the standard library.

Discover the ecosystem of Crystal libraries.

Instructions on how to use the compiler and tools.

Announcements about the language development.

If you want to dive into the development of Crystal, these materials give some guidance.

A guide on how to open issues and contribute code to the Crystal project.

Our standards and expectations about working together as a community.

How we take the decisions that guide the language and its community.