Redux

Redux is a JavaScript library for predictable and maintainable global state management, created by Dan Abramov and Andrew Clark in 2015 and now downloaded over 6 million times weekly on npm. The library implements a single source of truth pattern where the entire application state lives in one plain JavaScript object tree, updated exclusively through dispatched action objects processed by pure reducer functions. This unidirectional data flow makes application behavior deterministic, enabling undo and redo, state persistence, and server-side rendering from the same state. The Redux DevTools browser extension provides time-travel debugging, allowing developers to step forward and backward through every state change, inspect action payloads, and automatically generate error reports containing the complete state diff. Redux works with any UI layer through its store subscription API, with official React bindings provided by React-Redux using the useSelector and useDispatch hooks for optimized re-rendering. Redux Toolkit, the official batteries-included toolset, reduces boilerplate by up to 75 percent through configureStore, createSlice, createAsyncThunk, and createEntityAdapter utilities, making Redux development efficient for both beginners and large teams. The ecosystem includes Reselect for memoized selectors, Redux Thunk and Redux Saga for async logic, Redux Persist for state rehydration from storage, RTK Query for data fetching and caching, and hundreds of community middleware packages. Redux powers state management at companies including Instagram, WhatsApp, Twitter, Microsoft Teams, and Baidu. Copyright 2015-2026.