diff --git a/packages/docs/package.json b/packages/docs/package.json
index 1b10df9..e4b1c3f 100644
--- a/packages/docs/package.json
+++ b/packages/docs/package.json
@@ -11,7 +11,7 @@
     "typecheck": "tsc --noEmit"
   },
   "dependencies": {
-    "@funstack/router": "^1.2.0",
+    "@funstack/router": "^1.4.0",
     "@funstack/static": "workspace:*",
     "@shikijs/rehype": "^4.4.3",
     "@types/node": "catalog:",
diff --git a/packages/docs/src/pages/learn/FileSystemRouting.mdx b/packages/docs/src/pages/learn/FileSystemRouting.mdx
index 11daafb..1205af8 100644
--- a/packages/docs/src/pages/learn/FileSystemRouting.mdx
+++ b/packages/docs/src/pages/learn/FileSystemRouting.mdx
@@ -118,7 +118,7 @@ export default function BlogPost({ params }: { params: { slug: string } }) {
 }
 ```
 
-This generates `blog/hello.html` and `blog/world.html`. Each page component receives the resolved `params` as a prop.
+This generates `blog/hello.html` and `blog/world.html`. Each page component receives the resolved `params` as a prop (see [Params on Client-Side Navigation](#params-on-client-side-navigation) for how `params` behaves when navigating in the browser).
 
 A dynamic route **must** export `generateStaticParams`; the build fails otherwise. A static site can only serve pages that were enumerated at build time, so a dynamic route without it would produce no output.
 
@@ -132,7 +132,58 @@ export function generateStaticParams() {
 export { default } from "./_page"; // _page.tsx is marked "use client"
 ```
 
-> **Note:** Because static hosting serves one pre-rendered RSC payload per page, soft client-side navigation between different values of the _same_ dynamic route reflects the params of the initially-loaded page. Loading a dynamic URL directly always renders the correct params. Static routes and layouts navigate fully on the client.
+## Params on Client-Side Navigation
+
+Loading any generated URL directly always renders the correct params. During soft client-side navigation between pages of the _same_ dynamic route (say, from `/blog/hello` to `/blog/world`), what the `params` prop holds depends on the kind of the component:
+
+- **Client Components** (pages and layouts marked `"use client"`) are rendered by FUNSTACK Router in the browser, so they receive the **live** params of the URL currently shown. They stay correct across soft navigation.
+- **Server Components** render once at build time, so their `params` prop — and their entire rendered output — currently reflects the values the page was generated with after such a navigation. This is a temporary limitation, not the intended end state: the destination page's pre-rendered RSC payload exists in the build output, and loading it on client-side navigation so that Server Component pages update too is being worked on ([#174](https://github.com/uhyo/funstack-static/issues/174)). Until then, use the route object below to read live params, or make the page body a Client Component if it must fully react to param changes.
+
+### Reading Live Params with the Route Object
+
+Every page and layout receives a `route` prop: an opaque **route object** identifying its route. In a Client Component, hand it to FUNSTACK Router's [`useRouteParams`](https://github.com/uhyo/funstack-router) hook to read the live params of the current URL. A Server Component cannot use hooks itself, but can forward the prop to a Client Component:
+
+```tsx
+// src/pages/blog/[slug]/page.tsx (a Server Component)
+import type { FsRouteComponentProps } from "@funstack/static/fs-routes";
+import { LiveSlug } from "./live-slug";
+
+export function generateStaticParams() {
+  return [{ slug: "hello" }, { slug: "world" }];
+}
+
+export default function BlogPost({
+  params,
+  route,
+}: FsRouteComponentProps<{ slug: string }>) {
+  return (
+    <article>
+      Post generated for: {params.slug}
+      <LiveSlug route={route} />
+    </article>
+  );
+}
+```
+
+```tsx
+// src/pages/blog/[slug]/live-slug.tsx
+"use client";
+import { useRouteParams } from "@funstack/router";
+import type { FsRouteObject } from "@funstack/static/fs-routes";
+
+export function LiveSlug({
+  route,
+}: {
+  route: FsRouteObject<{ slug: string }>;
+}) {
+  const params = useRouteParams(route); // params of the URL currently shown
+  return <p>Now viewing: {params.slug}</p>;
+}
+```
+
+The `FsRouteComponentProps<Params>` helper types the `params` and `route` props any page or layout receives. Like the `params` prop itself, the `Params` type argument is declared by you and not verified against the route's path.
+
+The `route` prop reaches the two kinds of components differently, with the same result: FUNSTACK Static passes it to Server Components at build time, while FUNSTACK Router (v1.4.0 or later) passes it to Client Components at render time — along with the live `params` and its other [route component props](https://github.com/uhyo/funstack-router).
 
 ## Custom Conventions (Adapters)
 
diff --git a/packages/example-fs-routing/package.json b/packages/example-fs-routing/package.json
index d9aacb3..41c08fc 100644
--- a/packages/example-fs-routing/package.json
+++ b/packages/example-fs-routing/package.json
@@ -10,7 +10,7 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "@funstack/router": "^1.2.0",
+    "@funstack/router": "^1.4.0",
     "@funstack/static": "workspace:*",
     "@types/node": "catalog:",
     "react": "catalog:",
diff --git a/packages/static/e2e/fixture-fs-routing/package.json b/packages/static/e2e/fixture-fs-routing/package.json
index 6683ba8..a94d235 100644
--- a/packages/static/e2e/fixture-fs-routing/package.json
+++ b/packages/static/e2e/fixture-fs-routing/package.json
@@ -3,7 +3,7 @@
   "private": true,
   "type": "module",
   "devDependencies": {
-    "@funstack/router": "^1.2.0",
+    "@funstack/router": "^1.4.0",
     "@funstack/static": "workspace:*",
     "@types/react": "^19.2.18",
     "@types/react-dom": "^19.2.4",
diff --git a/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/_page.tsx b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/_page.tsx
new file mode 100644
index 0000000..448e457
--- /dev/null
+++ b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/_page.tsx
@@ -0,0 +1,26 @@
+"use client";
+import { useRouteParams } from "@funstack/router";
+import type { FsRouteComponentProps } from "@funstack/static/fs-routes";
+
+// A Client Component page: the router renders it with the live params of the
+// current match (and its route object), so it stays correct across soft
+// client-side navigation.
+export default function ClientLangPage({
+  params,
+  route,
+}: FsRouteComponentProps<{ lang: string }>) {
+  const liveParams = useRouteParams(route);
+  return (
+    <div>
+      <p data-testid="page-id">lang-client</p>
+      <p data-testid="client-page-lang">{params.lang}</p>
+      <p data-testid="client-page-hook-lang">{liveParams.lang}</p>
+      <a href="/en/client" data-testid="link-en-client">
+        English client page
+      </a>{" "}
+      <a href="/ja/client" data-testid="link-ja-client">
+        Japanese client page
+      </a>
+    </div>
+  );
+}
diff --git a/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/page.tsx b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/page.tsx
new file mode 100644
index 0000000..770f500
--- /dev/null
+++ b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/client/page.tsx
@@ -0,0 +1,6 @@
+// generateStaticParams runs at build time, so it lives in this Server
+// Component module while the page body is a Client Component.
+export function generateStaticParams() {
+  return [{ lang: "en" }, { lang: "ja" }];
+}
+export { default } from "./_page";
diff --git a/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/layout.tsx b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/layout.tsx
new file mode 100644
index 0000000..7e3dfe9
--- /dev/null
+++ b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/layout.tsx
@@ -0,0 +1,16 @@
+"use client";
+import { Outlet, useLocation } from "@funstack/router";
+
+// A Client Component layout under a dynamic segment: the router renders it
+// with the params of the current match, so `params` stays live across soft
+// client-side navigation.
+export default function LangLayout({ params }: { params: { lang: string } }) {
+  const location = useLocation();
+  return (
+    <section>
+      <p data-testid="lang-layout-pathname">{location.pathname}</p>
+      <p data-testid="lang-layout-lang">{params.lang}</p>
+      <Outlet />
+    </section>
+  );
+}
diff --git a/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/live-lang.tsx b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/live-lang.tsx
new file mode 100644
index 0000000..b920869
--- /dev/null
+++ b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/live-lang.tsx
@@ -0,0 +1,14 @@
+"use client";
+import { useRouteParams } from "@funstack/router";
+import type { FsRouteObject } from "@funstack/static/fs-routes";
+
+// A Client Component under a Server Component page reading the live params
+// of the current URL through the route object.
+export function LiveLang({
+  route,
+}: {
+  route: FsRouteObject<{ lang: string }>;
+}) {
+  const params = useRouteParams(route);
+  return <p data-testid="live-lang">{params.lang}</p>;
+}
diff --git a/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/page.tsx b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/page.tsx
new file mode 100644
index 0000000..6ab1a4b
--- /dev/null
+++ b/packages/static/e2e/fixture-fs-routing/src/pages/[lang]/page.tsx
@@ -0,0 +1,30 @@
+import type { FsRouteComponentProps } from "@funstack/static/fs-routes";
+import { LiveLang } from "./live-lang";
+
+export function generateStaticParams() {
+  return [{ lang: "en" }, { lang: "ja" }];
+}
+
+// A Server Component page: rendered at build time with the concrete params,
+// and given its route object to hand to Client Components for live params.
+export default function LangPage({
+  params,
+  route,
+}: FsRouteComponentProps<{ lang: string }>) {
+  return (
+    <div>
+      <p data-testid="page-id">lang</p>
+      <p data-testid="lang-page-lang">{params.lang}</p>
+      <LiveLang route={route} />
+      <a href="/en" data-testid="link-en">
+        English
+      </a>{" "}
+      <a href="/ja" data-testid="link-ja">
+        Japanese
+      </a>{" "}
+      <a href="/en/client" data-testid="link-en-client">
+        English client page
+      </a>
+    </div>
+  );
+}
diff --git a/packages/static/e2e/tests-dev/fs-routing.spec.ts b/packages/static/e2e/tests-dev/fs-routing.spec.ts
index 57227e4..4c3a65e 100644
--- a/packages/static/e2e/tests-dev/fs-routing.spec.ts
+++ b/packages/static/e2e/tests-dev/fs-routing.spec.ts
@@ -36,4 +36,24 @@ test.describe("File-system routing (dev server)", () => {
     await page.getByRole("link", { name: "About" }).click();
     await expect(page.getByTestId("page-id")).toHaveText("about");
   });
+
+  test("a Client Component layout receives live params on soft navigation", async ({
+    page,
+  }) => {
+    await page.goto("/ja");
+    await expect(page.getByTestId("lang-layout-lang")).toHaveText("ja");
+
+    await page.getByTestId("link-en").click();
+    await expect(page.getByTestId("lang-layout-lang")).toHaveText("en");
+  });
+
+  test("a Client Component reads live params via the route object", async ({
+    page,
+  }) => {
+    await page.goto("/ja");
+    await expect(page.getByTestId("live-lang")).toHaveText("ja");
+
+    await page.getByTestId("link-en").click();
+    await expect(page.getByTestId("live-lang")).toHaveText("en");
+  });
 });
diff --git a/packages/static/e2e/tests/fs-routing.spec.ts b/packages/static/e2e/tests/fs-routing.spec.ts
index 2b128ac..d0f1165 100644
--- a/packages/static/e2e/tests/fs-routing.spec.ts
+++ b/packages/static/e2e/tests/fs-routing.spec.ts
@@ -11,6 +11,10 @@ test.describe("File-system routing build output", () => {
       "/blog/world",
       "/dashboard",
       "/dashboard/settings",
+      "/en",
+      "/ja",
+      "/en/client",
+      "/ja/client",
     ]) {
       const response = await request.get(path);
       expect(response.ok(), `expected ${path} to be served`).toBe(true);
@@ -84,6 +88,17 @@ test.describe("File-system routing rendering", () => {
     await expect(page.getByTestId("page-id")).toHaveText("dashboard");
   });
 
+  test("renders correct params when a dynamic page is loaded directly", async ({
+    page,
+  }) => {
+    for (const lang of ["en", "ja"]) {
+      await page.goto(`/${lang}`);
+      await expect(page.getByTestId("lang-layout-lang")).toHaveText(lang);
+      await expect(page.getByTestId("lang-page-lang")).toHaveText(lang);
+      await expect(page.getByTestId("live-lang")).toHaveText(lang);
+    }
+  });
+
   test("no JavaScript errors while navigating", async ({ page }) => {
     const errors: string[] = [];
     page.on("pageerror", (error) => {
@@ -96,3 +111,55 @@ test.describe("File-system routing rendering", () => {
     expect(errors).toEqual([]);
   });
 });
+
+test.describe("Dynamic params on soft client-side navigation", () => {
+  test("a Client Component layout receives live params", async ({ page }) => {
+    await page.goto("/ja");
+    await expect(page.getByTestId("lang-layout-lang")).toHaveText("ja");
+
+    await page.getByTestId("link-en").click();
+    await expect(page.getByTestId("lang-layout-pathname")).toHaveText("/en");
+    await expect(page.getByTestId("lang-layout-lang")).toHaveText("en");
+  });
+
+  test("a Client Component page receives live params and its route object", async ({
+    page,
+  }) => {
+    await page.goto("/en/client");
+    await expect(page.getByTestId("client-page-lang")).toHaveText("en");
+    await expect(page.getByTestId("client-page-hook-lang")).toHaveText("en");
+
+    await page.getByTestId("link-ja-client").click();
+    await expect(page.getByTestId("client-page-lang")).toHaveText("ja");
+    await expect(page.getByTestId("client-page-hook-lang")).toHaveText("ja");
+  });
+
+  test("a Client Component reads live params via the route object under a Server Component page", async ({
+    page,
+  }) => {
+    await page.goto("/ja");
+    await expect(page.getByTestId("live-lang")).toHaveText("ja");
+
+    await page.getByTestId("link-en").click();
+    await expect(page.getByTestId("live-lang")).toHaveText("en");
+    // The Server Component page's own output was rendered at build time and
+    // keeps its build-time params — the documented static-hosting limitation.
+    await expect(page.getByTestId("lang-page-lang")).toHaveText("ja");
+  });
+
+  test("no JavaScript errors while navigating between dynamic pages", async ({
+    page,
+  }) => {
+    const errors: string[] = [];
+    page.on("pageerror", (error) => {
+      errors.push(error.message);
+    });
+    await page.goto("/ja");
+    await page.waitForLoadState("networkidle");
+    await page.getByTestId("link-en").click();
+    await expect(page.getByTestId("lang-layout-lang")).toHaveText("en");
+    await page.getByTestId("link-en-client").click();
+    await expect(page.getByTestId("client-page-lang")).toHaveText("en");
+    expect(errors).toEqual([]);
+  });
+});
diff --git a/packages/static/package.json b/packages/static/package.json
index acf63f8..7bf5cb9 100644
--- a/packages/static/package.json
+++ b/packages/static/package.json
@@ -64,7 +64,7 @@
   "author": "uhyo <uhyo@uhy.ooo>",
   "license": "MIT",
   "devDependencies": {
-    "@funstack/router": "^1.2.0",
+    "@funstack/router": "^1.4.0",
     "@playwright/test": "^1.62.1",
     "@types/node": "catalog:",
     "@types/react": "^19.2.18",
@@ -84,7 +84,7 @@
     "srvx": "^0.12.5"
   },
   "peerDependencies": {
-    "@funstack/router": "^1.2.0",
+    "@funstack/router": "^1.4.0",
     "react": "^19.2.3",
     "react-dom": "^19.2.3",
     "vite": "^7.0.0 || ^8.0.0"
diff --git a/packages/static/src/fs-routes/index.ts b/packages/static/src/fs-routes/index.ts
index 35bb34b..173f073 100644
--- a/packages/static/src/fs-routes/index.ts
+++ b/packages/static/src/fs-routes/index.ts
@@ -9,8 +9,10 @@
 export { nextRoutes, type NextRoutesOptions } from "./nextAdapter";
 export type {
   FsRoutesAdapter,
+  FsRouteComponentProps,
   FsRouteFile,
   FsRouteModule,
+  FsRouteObject,
   FsRouteTreeNode,
   FsRootComponent,
   MaybePromise,
diff --git a/packages/static/src/fs-routes/runtime.test.ts b/packages/static/src/fs-routes/runtime.test.ts
new file mode 100644
index 0000000..467964f
--- /dev/null
+++ b/packages/static/src/fs-routes/runtime.test.ts
@@ -0,0 +1,113 @@
+import { isValidElement } from "react";
+import { describe, expect, it } from "vitest";
+import { createFsRoutesEntries } from "./runtime";
+import type { EntryDefinition } from "../entryDefinition";
+import type { FsRouteComponentProps, FsRouteModule } from "./types";
+
+function clientReference(): () => never {
+  return Object.defineProperties(
+    (): never => {
+      throw new Error("Unexpectedly client reference is called on server");
+    },
+    { $$typeof: { value: Symbol.for("react.client.reference") } },
+  );
+}
+
+const Root = ({ children }: { children: React.ReactNode }) => children;
+
+interface DefinitionLike {
+  id?: string;
+  path?: string;
+  component?: unknown;
+  children?: DefinitionLike[];
+}
+
+/**
+ * Renders an entry's `FsRoutesApp` element (a plain function component) to
+ * obtain the Router element and returns its route definitions.
+ */
+function routesOfEntry(entry: EntryDefinition): DefinitionLike[] {
+  const app = entry.app as React.ReactElement<object> & {
+    type: (props: object) => React.ReactElement<{ routes: DefinitionLike[] }>;
+  };
+  return app.type(app.props).props.routes;
+}
+
+function collectDefinitions(
+  definitions: DefinitionLike[],
+  into: DefinitionLike[] = [],
+): DefinitionLike[] {
+  for (const definition of definitions) {
+    into.push(definition);
+    if (definition.children) {
+      collectDefinitions(definition.children, into);
+    }
+  }
+  return into;
+}
+
+async function entriesFor(
+  modules: Record<string, FsRouteModule>,
+): Promise<EntryDefinition[]> {
+  const getEntries = createFsRoutesEntries({
+    modules,
+    base: "./pages",
+    root: Root,
+  });
+  const entries: EntryDefinition[] = [];
+  for await (const entry of getEntries()) {
+    entries.push(entry);
+  }
+  return entries;
+}
+
+describe("createFsRoutesEntries route definitions", () => {
+  const clientLayout = clientReference();
+  const modules: Record<string, FsRouteModule> = {
+    "./pages/[lang]/layout.tsx": { default: clientLayout },
+    "./pages/[lang]/page.tsx": {
+      default: () => null,
+      generateStaticParams: () => [{ lang: "en" }, { lang: "ja" }],
+    },
+    "./pages/about/page.tsx": { default: () => null },
+  };
+
+  it("passes a Client Component as a component type so the router renders it with live params", async () => {
+    const entries = await entriesFor(modules);
+    const routes = routesOfEntry(entries.find((e) => e.path === "en.html")!);
+    const layout = routes.find((d) => d.path === "/:lang")!;
+    expect(layout.component).toBe(clientLayout);
+  });
+
+  it("renders a Server Component with build-time params and its route object", async () => {
+    const entries = await entriesFor(modules);
+    const routes = routesOfEntry(entries.find((e) => e.path === "ja.html")!);
+    const layout = routes.find((d) => d.path === "/:lang")!;
+    const page = layout.children!.find((d) => d.path === "/")!;
+    expect(isValidElement(page.component)).toBe(true);
+    const props = (page.component as React.ReactElement<FsRouteComponentProps>)
+      .props;
+    expect(props.params).toEqual({ lang: "ja" });
+    expect(props.route).toEqual({ id: page.id });
+  });
+
+  it("assigns a unique id to every route definition", async () => {
+    const entries = await entriesFor(modules);
+    for (const entry of entries) {
+      const definitions = collectDefinitions(routesOfEntry(entry));
+      const ids = definitions.map((d) => d.id);
+      expect(ids.every((id) => typeof id === "string" && id !== "")).toBe(true);
+      expect(new Set(ids).size).toBe(ids.length);
+    }
+  });
+
+  it("assigns the same ids on every page so route objects stay portable", async () => {
+    const entries = await entriesFor(modules);
+    const idsPerEntry = entries.map((entry) =>
+      collectDefinitions(routesOfEntry(entry)).map((d) => `${d.path} ${d.id}`),
+    );
+    for (const ids of idsPerEntry) {
+      expect(ids).toEqual(idsPerEntry[0]);
+    }
+  });
+});
diff --git a/packages/static/src/fs-routes/runtime.tsx b/packages/static/src/fs-routes/runtime.tsx
index a8ecff2..546317f 100644
--- a/packages/static/src/fs-routes/runtime.tsx
+++ b/packages/static/src/fs-routes/runtime.tsx
@@ -3,7 +3,9 @@ import { Router } from "@funstack/router";
 import type { RouteDefinition } from "@funstack/router/server";
 import type {
   FsRootComponent,
+  FsRouteComponentProps,
   FsRouteModule,
+  FsRouteObject,
   FsRoutesAdapter,
   FsRouteTreeNode,
 } from "./types";
@@ -14,6 +16,7 @@ import {
   modulesToRouteFiles,
   urlPathToFilePath,
 } from "./tree";
+import { isClientReference } from "../util/clientReference";
 
 /**
  * Options for {@link createFsRoutesEntries}.
@@ -82,25 +85,52 @@ export function createFsRoutesEntries(
   function buildRouteDefinitions(
     nodes: FsRouteTreeNode[],
     params: Record<string, string>,
+    idPrefix: string,
   ): RouteDefinition[] {
-    return nodes.map((node): RouteDefinition => {
+    return nodes.map((node, index): RouteDefinition => {
       const Component = node.module.default;
+      // Unique id (by tree position) so that the route object passed to the
+      // component resolves to this route's context in the typed hooks; the
+      // file path is appended for legible debugging output.
+      const id = `${idPrefix}${index}${
+        node.filePath === undefined ? "" : ` ${node.filePath}`
+      }`;
       const definition: {
+        id: string;
         path?: string;
-        component?: React.ReactNode;
+        component?: React.ComponentType<object> | React.ReactNode;
         children?: RouteDefinition[];
-      } = {};
+      } = { id };
       if (node.path !== undefined) {
         definition.path = node.path;
       }
       if (Component) {
-        definition.component = createElement(
-          Component as React.ComponentType<{ params: Record<string, string> }>,
-          { params },
-        );
+        if (isClientReference(Component)) {
+          // A Client Component crosses the RSC boundary as a reference, so
+          // the router can render it in the browser. Pass the component
+          // itself so it receives the params of the current match, keeping
+          // them live across soft client-side navigation.
+          definition.component = Component as React.ComponentType<object>;
+        } else {
+          // A Server Component crosses the RSC boundary only as its rendered
+          // output, so it must be rendered here with the build-time params.
+          // The route object lets Client Components below it read the live
+          // params through FUNSTACK Router's typed hooks.
+          // The typed hooks resolve a route object by its runtime `id`; the
+          // branding symbol of `RouteHandle` is type-level only.
+          const route = { id } as unknown as FsRouteObject;
+          definition.component = createElement(
+            Component as React.ComponentType<FsRouteComponentProps>,
+            { params, route },
+          );
+        }
       }
       if (node.children) {
-        definition.children = buildRouteDefinitions(node.children, params);
+        definition.children = buildRouteDefinitions(
+          node.children,
+          params,
+          `${idPrefix}${index}.`,
+        );
       }
       return definition;
     });
@@ -115,7 +145,7 @@ export function createFsRoutesEntries(
     path: string;
     params: Record<string, string>;
   }): React.ReactNode {
-    const routes = buildRouteDefinitions(tree, params);
+    const routes = buildRouteDefinitions(tree, params, "");
     return createElement(Router, { routes, fallback: "static", ssr: { path } });
   }
 
diff --git a/packages/static/src/fs-routes/tree.ts b/packages/static/src/fs-routes/tree.ts
index 0108c4f..1df89e0 100644
--- a/packages/static/src/fs-routes/tree.ts
+++ b/packages/static/src/fs-routes/tree.ts
@@ -1,3 +1,4 @@
+import { isClientReference } from "../util/clientReference";
 import type { FsRouteFile, FsRouteModule, FsRouteTreeNode } from "./types";
 
 /**
@@ -94,21 +95,6 @@ function isDynamicSegment(segment: string): boolean {
   return segment.startsWith(":");
 }
 
-const CLIENT_REFERENCE = Symbol.for("react.client.reference");
-
-/**
- * Whether a module export is a client reference, meaning the module is marked
- * `"use client"`. React's `registerClientReference` tags every such export
- * with `$$typeof`.
- */
-function isClientReference(value: unknown): boolean {
-  return (
-    typeof value === "function" &&
-    "$$typeof" in value &&
-    value.$$typeof === CLIENT_REFERENCE
-  );
-}
-
 /**
  * Formats the source file of a route for an error message, when known.
  */
diff --git a/packages/static/src/fs-routes/types.ts b/packages/static/src/fs-routes/types.ts
index 9872ac2..bfefa43 100644
--- a/packages/static/src/fs-routes/types.ts
+++ b/packages/static/src/fs-routes/types.ts
@@ -1,7 +1,51 @@
+import type { RouteHandle } from "@funstack/router";
 import type { ComponentType, ReactNode } from "react";
 
 export type MaybePromise<T> = T | Promise<T>;
 
+/**
+ * Opaque route object identifying the route of a page or layout, received as
+ * the `route` prop. Give it to FUNSTACK Router's typed hooks
+ * (`useRouteParams(route)`, in a Client Component) to read the params of the
+ * URL currently shown, which may differ from a Server Component's build-time
+ * `params` prop after soft client-side navigation between pages of the same
+ * dynamic route.
+ *
+ * The `Params` type argument describes the route's dynamic params; like the
+ * `params` prop it is not verified against the route's actual path.
+ *
+ * @experimental File-system routing is experimental and not yet subject to
+ * semantic versioning.
+ */
+export type FsRouteObject<
+  Params extends Record<string, string> = Record<string, string>,
+> = RouteHandle<string, Params, unknown, undefined>;
+
+/**
+ * Props received by every page or layout under file-system routing: the
+ * route's dynamic `params`, and the {@link FsRouteObject | route object}
+ * identifying its route.
+ *
+ * A Server Component receives exactly these props, with the `params` the
+ * page was generated with. A Client Component is rendered by FUNSTACK Router
+ * with the live `params` of the current match, plus the router's other route
+ * component props; these two are the subset shared by both kinds.
+ *
+ * @experimental File-system routing is experimental and not yet subject to
+ * semantic versioning.
+ */
+export interface FsRouteComponentProps<
+  Params extends Record<string, string> = Record<string, string>,
+> {
+  /**
+   * Dynamic route params. Build-time values for a Server Component; live
+   * values for a Client Component.
+   */
+  params: Params;
+  /** Opaque route object for FUNSTACK Router's typed hooks. */
+  route: FsRouteObject<Params>;
+}
+
 /**
  * Module shape for a discovered route file (a page or a layout).
  *
@@ -11,7 +55,10 @@ export type MaybePromise<T> = T | Promise<T>;
  */
 export interface FsRouteModule {
   /** The component for this page or layout. */
-  default?: ComponentType<{ params: Record<string, string> }> | ComponentType;
+  default?:
+    | ComponentType<FsRouteComponentProps>
+    | ComponentType<{ params: Record<string, string> }>
+    | ComponentType;
   /**
    * Function used to statically generate a dynamic route. Required for pages
    * whose route contains a dynamic segment; the build fails without it, since
diff --git a/packages/static/src/util/clientReference.ts b/packages/static/src/util/clientReference.ts
new file mode 100644
index 0000000..49cc812
--- /dev/null
+++ b/packages/static/src/util/clientReference.ts
@@ -0,0 +1,14 @@
+const CLIENT_REFERENCE = Symbol.for("react.client.reference");
+
+/**
+ * Whether a module export is a client reference, meaning the module is marked
+ * `"use client"`. React's `registerClientReference` tags every such export
+ * with `$$typeof`.
+ */
+export function isClientReference(value: unknown): boolean {
+  return (
+    typeof value === "function" &&
+    "$$typeof" in value &&
+    value.$$typeof === CLIENT_REFERENCE
+  );
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 521667a..161e7a3 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -42,8 +42,8 @@ importers:
   packages/docs:
     dependencies:
       '@funstack/router':
-        specifier: ^1.2.0
-        version: 1.2.0(react@19.2.8)
+        specifier: ^1.4.0
+        version: 1.4.0(react-dom@19.2.8(react@19.2.8))(react@19.2.8)
       '@funstack/static':
         specifier: workspace:*
         version: link:../static
@@ -125,8 +125,8 @@ importers:
   packages/example-fs-routing:
     dependencies:
       '@funstack/router':
-        specifier: ^1.2.0
-        version: 1.2.0(react@19.2.8)
+        specifier: ^1.4.0
+        version: 1.4.0(react-dom@19.2.8(react@19.2.8))(react@19.2.8)
       '@funstack/static':
         specifier: workspace:*
         version: link:../static
@@ -172,8 +172,8 @@ importers:
         version: 0.12.5
     devDependencies:
       '@funstack/router':
-        specifier: ^1.2.0
-        version: 1.2.0(react@19.2.8)
+        specifier: ^1.4.0
+        version: 1.4.0(react-dom@19.2.8(react@19.2.8))(react@19.2.8)
       '@playwright/test':
         specifier: ^1.62.1
         version: 1.62.1
@@ -232,8 +232,8 @@ importers:
   packages/static/e2e/fixture-fs-routing:
     devDependencies:
       '@funstack/router':
-        specifier: ^1.2.0
-        version: 1.2.0(react@19.2.8)
+        specifier: ^1.4.0
+        version: 1.4.0(react-dom@19.2.8(react@19.2.8))(react@19.2.8)
       '@funstack/static':
         specifier: workspace:*
         version: link:../..
@@ -383,8 +383,8 @@ packages:
       '@csstools/css-parser-algorithms': ^4.0.0
       '@csstools/css-tokenizer': ^4.0.0
 
-  '@csstools/css-color-parser@4.2.0':
-    resolution: {integrity: sha512-5+5LEmFuY1AjXdYhmgjTJogtQnP1evJ1zrBZGUNZ0thkpwnnmKxcHdAMn/OtFjAb25zA+jKDVYVRl+5G7rjv1A==}
+  '@csstools/css-color-parser@4.2.1':
+    resolution: {integrity: sha512-YpAJZhaHplYQkG8ib+/Fx5Y0eF2lVWi3tIvMJA6i39TLyUNp2439cifzW8VMjhlqrBjHzK5hVGugRRm2zTKI/A==}
     engines: {node: '>=20.19.0'}
     peerDependencies:
       '@csstools/css-parser-algorithms': ^4.0.0
@@ -396,8 +396,8 @@ packages:
     peerDependencies:
       '@csstools/css-tokenizer': ^4.0.0
 
-  '@csstools/css-syntax-patches-for-csstree@1.1.8':
-    resolution: {integrity: sha512-CpMLjAvwQg3BL5S0IeqsZNMH7EQrEWi0kLKOC13ZBF0ZwERiLWlibNPJr8G1kdU3Ms/r2KiNrF81pUh2HwAHdg==}
+  '@csstools/css-syntax-patches-for-csstree@1.1.9':
+    resolution: {integrity: sha512-iGGw4OsAYsS6pD29MdJ2bX/nJx65a04ZZiw6x+VwWlP2DdXf6f++Zmuv/OzALpdyfVhjbduIIF2cXM7HWBIe9A==}
     peerDependencies:
       css-tree: ^3.2.1
     peerDependenciesMeta:
@@ -750,11 +750,12 @@ packages:
       '@noble/hashes':
         optional: true
 
-  '@funstack/router@1.2.0':
-    resolution: {integrity: sha512-Y2OLyxcqx+TaijRa/MyA2ue7bk5svIPhjx/yvKHeQ1gB6O7gdI+D5gnuWn4W6zLuGmAXeopWd9Qco1AdnPWwQQ==}
+  '@funstack/router@1.4.0':
+    resolution: {integrity: sha512-hGBtHzNGWiCWzM+THX30oMk4wIzpfEVuIjFbh7vDz2F2gOZhHh+pbUB86VxxbWj+mLoadxts7d0JLDVK3IFRNw==}
     hasBin: true
     peerDependencies:
       react: ^19.2.0
+      react-dom: ^19.2.0
 
   '@funstack/skill-installer@1.1.0':
     resolution: {integrity: sha512-reB4V8FE8foqDULiqOhrlMq5ZqrdKpqlM8ulU/gtklf9OW71O4w5z5EZWjzygmIthmTriDo745EcRGm5+DQR1w==}
@@ -2764,11 +2765,11 @@ packages:
     resolution: {integrity: sha512-yau8yJdTt989Mm0Bd/236QnzEiPf2xLLTqUZRUJOo/3CB078LSwzei343DgtJVmfJKJE3TMINY1u42SQsP6mXw==}
     engines: {node: '>=14.0.0'}
 
-  tldts-core@7.4.10:
-    resolution: {integrity: sha512-KnQjp53ZekKgm/r3l+u8kJGGzYgrWdP8+Mql7a4vijh2WE0IrZWspQj/TpTxDho/YxO+AnOZnIjQcCD+q6iJsw==}
+  tldts-core@7.4.11:
+    resolution: {integrity: sha512-CW3WN2rIIE/Of21mulhgnGOwoDyEFNygyIBOONSdyAuSATgMMUCpLeUlB+E8sAwA5xRV9hYPl+kyZ9citHCaKg==}
 
-  tldts@7.4.10:
-    resolution: {integrity: sha512-GgouD1B+sWwvkaEq8vXC15DjQitxbvs12oIXELpconwm+Tg3zfcEv4jgzq3vtKverDXsg3VI8aRgNL2Nra0Iog==}
+  tldts@7.4.11:
+    resolution: {integrity: sha512-aBiNayCfTQxuIJBm06M+xR14cYaYlDlSXZbgsnKzKNxDKUVq7KFwTjwBSsb7m9Y5xO8WfPnBc63WaYFMTGlvqw==}
     hasBin: true
 
   tough-cookie@6.0.2:
@@ -3068,7 +3069,7 @@ snapshots:
     dependencies:
       '@asamuzakjp/generational-cache': 1.0.1
       '@csstools/css-calc': 3.3.0(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)
-      '@csstools/css-color-parser': 4.2.0(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)
+      '@csstools/css-color-parser': 4.2.1(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)
       '@csstools/css-parser-algorithms': 4.0.0(@csstools/css-tokenizer@4.0.0)
       '@csstools/css-tokenizer': 4.0.0
     optional: true
@@ -3129,7 +3130,7 @@ snapshots:
       '@csstools/css-tokenizer': 4.0.0
     optional: true
 
-  '@csstools/css-color-parser@4.2.0(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)':
+  '@csstools/css-color-parser@4.2.1(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)':
     dependencies:
       '@csstools/color-helpers': 6.1.1
       '@csstools/css-calc': 3.3.0(@csstools/css-parser-algorithms@4.0.0(@csstools/css-tokenizer@4.0.0))(@csstools/css-tokenizer@4.0.0)
@@ -3142,7 +3143,7 @@ snapshots:
       '@csstools/css-tokenizer': 4.0.0
     optional: true
 
-  '@csstools/css-syntax-patches-for-csstree@1.1.8(css-tree@3.2.1)':
+  '@csstools/css-syntax-patches-for-csstree@1.1.9(css-tree@3.2.1)':
     optionalDependencies:
       css-tree: 3.2.1
     optional: true
@@ -3346,10 +3347,11 @@ snapshots:
   '@exodus/bytes@1.15.1':
     optional: true
 
-  '@funstack/router@1.2.0(react@19.2.8)':
+  '@funstack/router@1.4.0(react-dom@19.2.8(react@19.2.8))(react@19.2.8)':
     dependencies:
       '@funstack/skill-installer': 1.1.0
       react: 19.2.8
+      react-dom: 19.2.8(react@19.2.8)
 
   '@funstack/skill-installer@1.1.0': {}
 
@@ -4520,7 +4522,7 @@ snapshots:
       '@asamuzakjp/css-color': 5.1.11
       '@asamuzakjp/dom-selector': 7.1.1
       '@bramus/specificity': 2.4.2
-      '@csstools/css-syntax-patches-for-csstree': 1.1.8(css-tree@3.2.1)
+      '@csstools/css-syntax-patches-for-csstree': 1.1.9(css-tree@3.2.1)
       '@exodus/bytes': 1.15.1
       css-tree: 3.2.1
       data-urls: 7.0.0
@@ -5334,17 +5336,17 @@ snapshots:
 
   tinyrainbow@3.1.1: {}
 
-  tldts-core@7.4.10:
+  tldts-core@7.4.11:
     optional: true
 
-  tldts@7.4.10:
+  tldts@7.4.11:
     dependencies:
-      tldts-core: 7.4.10
+      tldts-core: 7.4.11
     optional: true
 
   tough-cookie@6.0.2:
     dependencies:
-      tldts: 7.4.10
+      tldts: 7.4.11
     optional: true
 
   tr46@6.0.0: