Welcome to the documentation on the Redux Reducer Toolkit library. It is a library intended to help you build up both complicated reducer functions and complicated selector functions from simple parts. This document is a literate program, arranged as a book that can be read to understand the entirety of the library. The Concepts sections provide an overview of the major concepts and their implementions. They are designed to be read front-to-back. The Cookbook sections provide examples of patterns that are common in daily usage and can be read in any order. The Appendix sections contain useful miscellaneous information and implementation details.