Valtio vs Zustand

Valtio

• React developers who want simple shared state without a lot of boilerplate
• Developers who prefer mutating state directly instead of writing reducers or immutable updates
• Projects that need state outside components, subscribed to by plain JavaScript code
• Teams using React 19 who want to read async data with the use hook inside Suspense

Zustand

• React developers who want simpler shared state than Redux
• Apps that need state shared across many components without wrapping them in providers
• Projects that need to read or update state outside components via getState and setState
• Developers who want fine control over which state changes trigger re-renders

Valtio

• Mutations look like normal JavaScript, so there is little new syntax to learn
• Components re-render only for the state they actually read, according to the README
• Works in React and in vanilla JavaScript from the same core idea

Zustand

• Small, simple API based on hooks, with no providers required
• Components re-render only when the selected state they read changes
• Works with async actions and can be used outside React

Valtio

• Developers who want strictly immutable, reducer-based state, since Valtio uses mutation and snapshots instead
• Beginners who are not yet comfortable with proxies, as the README notes the snapshot and proxy split can be confusing at first
• Apps that need Suspense with useTransition to work smoothly, because the README says that pattern suffers from de-opt issues

Zustand

• Teams that require Redux's conventions, tooling, and strict structure, since the README describes zustand as un-opinionated
• Projects not using React or JavaScript, since the README focuses on JavaScript and React usage and the vanilla core is only a secondary option
• Adding state inside React Server Components, which the README explicitly advises against because it can cause bugs and privacy issues

Valtio

• Its TypeScript types for useSnapshot can be stricter than some users want, and the README points to a workaround
• The README notes that this in methods can behave unexpectedly, so arrow functions are recommended
• Suspense with use still has a de-opt issue that affects useTransition, with a third-party library suggested as a workaround

Zustand

• The README says to set state immutably and be careful when replacing state, which takes care to get right
• Some patterns, such as fetching everything or using custom equality, can cause extra re-renders or require extra setup
• Documentation for the migration to v5 and TypeScript usage is referenced but not included in the truncated README