# Server-Side Rendering \[Dehydrate on the server, hydrate with no refetch] SSR is on-demand; there is no prefetch API. Components declare their data with `useStateData` exactly as on the client; on the server (``) a cache miss suspends until the fetch settles. Results (fulfilled or rejected) are captured in the registry, serialized into the HTML, and ingested on the client so the first paint is already fulfilled: no loading flash, no re-fetch, no hydration mismatch. :::info\[Requirements] models carry a `name` and states a `key` (stable string identities — both required by their types), and `fetchFn` must work in both environments (it runs on the server during SSR and on the client for reloads). [Plain value fields](/rxfy/define-state#plain-value-fields) (bare Zod schemas in `model`) don't need a model `name` — they travel inside the keyed state's dehydrated value. Keep them JSON-serializable. ::: :::tip\[Building a synced app?] SSR also signs the channel **grants** a Sync Client uses to receive pushes. See [Grants](/framework/server/grants). ::: ## Buffered mode (any Node server) Wait for every Suspense boundary with `onAllReady`, then send the complete document. This is the recommended non-Next mode. Here it is wired end to end: a render function that resolves once every `useStateData` fetch has settled, an HTTP handler that injects the HTML and the dehydrated snapshot into an `index.html` template, and the client entry that hydrates it. :::code-group ```tsx [entry-server.tsx] import { PassThrough } from "node:stream"; import { StrictMode, Suspense } from "react"; import { renderToPipeableStream } from "react-dom/server"; import { createModelRegistry, dehydrate, hydrationScript } from "rxfy"; import { StoreProvider } from "rxfy-react"; import { App } from "./App"; // Runs on the server per request. Returns the rendered HTML plus the