Hydration state

Server

import { createStaticRouter, stringifyRouterState } from '@cookbook/router';

const router = createStaticRouter({ routes, url: request.url });
await router.start();

const hydrationJson = stringifyRouterState(router);

Escape/embed the JSON using the security rules of your server framework. Serialized router state is data, not markup.

Client

import { createRouter, deserializeRouterState } from '@cookbook/router';

const hydrationData = deserializeRouterState(window.__ROUTER_STATE__);
const router = createRouter({ routes, hydrationData });

The client history pathname and search must match the serialized location. The router rejects mismatched hydration instead of quietly rendering the wrong branch.

Hash behavior

Fragments are not sent in HTTP requests. A client-only hash difference is handled separately from pathname/search mismatch; do not try to reconstruct a server fragment that never existed.

Where this bites

Do not share a static router across requests. Router state, middleware results, and serialized location are request-scoped.