Valtio

Overview

Valtio makes React state management feel like plain JavaScript — mutate objects directly and React re-renders automatically. No reducers, no actions, no selectors. Wrap an object in proxy(), mutate it anywhere, and components that read the changed properties re-render. Based on JavaScript Proxy, it tracks which properties each component uses and only re-renders when those specific properties change.

When to Use

• Want the simplest possible state management
• Tired of Redux boilerplate or Zustand's set() function
• Sharing state between components without prop drilling
• State that's accessed/modified outside React (event handlers, WebSocket callbacks)
• Team prefers mutable patterns over immutable

Instructions

Setup