YuuState

A unified state model for sync & async data.

Built on the patterns you know. Refined into something simpler.
Inspired by Zustand & TanStack-Query.

Fine-grained reactivity, minimal boilerplate, zero dependencies.

Demo: https://afiiif.github.io/yuustate/

Installation:

npm install yuustate

Read the docs → https://yuustate.vercel.app

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Like Zustand, but has additional capabilities:

• No selectors: automatically optimizes re-renders
• Store events: onFirstSubscribe, onSubscribe, onUnsubscribe, onLastUnsubscribe
• Easier to set initial state on SSR/SSG
• Smaller bundle

Like TanStack Query, but:

• DX is very similar to Zustand → One mental model for sync & async
• Much smaller bundle than TanStack Query → With nearly the same capabilities

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Store (Global State)

A store is a global state container that can be used both inside and outside React.
With YuuState, creating a store is simple:

import { createStore } from "yuustate/react";

const useLawn = createStore({
  plants: 3,
  zombies: 1,
});

Use it inside a component:

function MyPlants() {
  const { plants } = useLawn(); // No selectors needed.

  return <div>Plants: {plants}</div>; // Only re-render when plants state changes
}

Update the state anywhere:

const addPlant = () => {
  useLawn.setState(prev => ({ plants: prev.plants + 1 }));
};

Query Store for Async State

Create a query store for async data with createQuery:

import { createQuery } from "yuustate/react";

const plantDetailQuery = createQuery(
  async ({ id }) => {
    const res = await fetch(`/api/plants/${id}`);
    return res.json();
  },
);

Use it in your component:

function PlantDetail({ id }) {
  const usePlantDetailQuery = plantDetailQuery({ id });
  const { data, error } = usePlantDetailQuery();

  if (!data && !error) return <div>Loading...</div>;
  if (error) return <div>Error: {error.message}</div>;

  return <div>Name: {data.name}, damage: {data.damage}</div>;
}

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Read the docs → https://yuustate.vercel.app