Guides and references for all you need to know about Flow
Never used a type system before or just new to Flow? Let's get you up and running in a few minutes. Read more
Have a question about using Flow? Check here first! Read more
Learn how to add Flow type annotations to your code: Primitives, Objects, Functions, Classes, and more. Read more
Define a fixed set of constants which create their own type. Exhaustively checked in switch statements. Read more
Learn how the type system in Flow works: Subtyping, Variance, Refinements, and more. Read more
How to use Flow from the command line. Including how to manage the Flow background process. Read more
Flow tries to work out of the box as much as possible, but can be configured to work with any codebase. Read more
Learn how to create and use library definitions for the third-party code your code depends on. Read more
Learn how to write types in .flow files. Read more
Learn how to suppress Flow's type errors. Read more
Learn how to use Flow to effectively type common and advanced React patterns. Read more
Detailed guides, tips, and resources on how to integrate Flow with different JavaScript tools. Read more
Detailed guides, tips, and resources on how to integrate Flow with different code editors. Read more
Learn how to configure Flow's linter to find potentially harmful code. Read more
Learn how to enable stricter type checking on a file-by-file basis. Read more