What are Astro's UI framework integrations?

Astro supports using components from multiple UI frameworks in the same project through official integrations. Add integrations: npx astro add react vue svelte solid. Use in Astro components: import Counter from '../components/Counter.jsx'; <Counter client:load />. You can mix frameworks in a single page — a React sidebar, a Vue slider, and a Svelte form can coexist. Each framework component is an independent island with its own hydration. Supported frameworks: React, Preact, Vue, Svelte, SolidJS, Lit, Alpine.js. Sharing state between islands: since islands are isolated, use nanostores (tiny, framework-agnostic state library) or native browser APIs (LocalStorage, URL params, CustomEvents) for cross-island communication. Important: Astro components (.astro) cannot be used as interactive islands — only framework components can be hydrated client-side. Astro components are always server-rendered.