Redux vs Relay: What are the differences?

What is Redux? Predictable state container for JavaScript apps. Redux helps you write applications that behave consistently, run in different environments (client, server, and native), and are easy to test. On top of that, it provides a great developer experience, such as live code editing combined with a time traveling debugger.

What is Relay? A JavaScript Framework for Building Data-Driven React Applications, by Facebook. Never again communicate with your data store using an imperative API. Simply declare your data requirements using GraphQL and let Relay figure out how and when to fetch your data.

Redux and Relay are primarily classified as "State Management Library" and "Javascript UI Libraries" tools respectively.

Some of the features offered by Redux are:

• Predictable state
• Easy testing
• Works with other view layers besides React

On the other hand, Relay provides the following key features:

• Build data driven apps
• Declarative style
• Mutate data on the client and server

Redux and Relay are both open source tools. It seems that Redux with 49.2K GitHub stars and 12.7K forks on GitHub has more adoption than Relay with 13K GitHub stars and 1.28K GitHub forks.

According to the StackShare community, Redux has a broader approval, being mentioned in 1021 company stacks & 803 developers stacks; compared to Relay, which is listed in 39 company stacks and 7 developer stacks.