useStore

UseStore is a React hook used by several state-management libraries to access a centralized store from within a component. The most widely known implementation is Zustand’s useStore, but the approach is used by other libraries under similar names. The hook enables components to read state and subscribe to changes without prop drilling, and to invoke mutators or actions defined on the store.

In libraries like Zustand, a store is created by a factory function that defines the initial state and any functions that mutate it. The useStore hook connects a component to that store. When invoked with a selector, such as state => state.user or state => state.counter, the hook returns the selected slice. The component will re-render only when that selected slice changes, based on a configurable equality comparison to avoid unnecessary updates.

The pattern supports partial subscriptions and derived data, improving performance in large applications. State updates can be triggered through actions or setters provided by the store, and many implementations support middleware for persistence, logging, or undo/redo. Although the exact API varies, a typical usage is to call useStore with a selector to read values and with methods to mutate them.

Limitations include tight coupling to a specific store instance and the need to ensure updates remain predictable in server-side rendering or when sharing stores across components. UseStore is not part of the official React API, so portability depends on the chosen library.

See also: Zustand, React hooks, state management patterns.