diff --git a/packages/qwik-router/src/buildtime/types.ts b/packages/qwik-router/src/buildtime/types.ts
index 83aa9c2d0d3..b01ff90a8af 100644
--- a/packages/qwik-router/src/buildtime/types.ts
+++ b/packages/qwik-router/src/buildtime/types.ts
@@ -130,7 +130,13 @@ export interface PluginOptions {
   mdxPlugins?: MdxPlugins;
   /** MDX Options https://mdxjs.com/ */
   mdx?: any;
-  /** The platform object which can be used to mock the Cloudflare bindings. */
+  /**
+   * Extend the `platform` object in RequestEvent, which can be used to e.g. mock Cloudflare
+   * bindings.
+   *
+   * This only works in **dev mode** and only when using the in-process Vite dev server middleware
+   * (the default).
+   */
   platform?: Record<string, unknown>;
   /** Configuration to rewrite url paths */
   rewriteRoutes?: RewriteRouteOption[];
diff --git a/packages/qwik-router/src/buildtime/vite/dev-middleware.ts b/packages/qwik-router/src/buildtime/vite/dev-middleware.ts
index 065315f70fb..aa3d8549046 100644
--- a/packages/qwik-router/src/buildtime/vite/dev-middleware.ts
+++ b/packages/qwik-router/src/buildtime/vite/dev-middleware.ts
@@ -63,7 +63,11 @@ export const makeRouterDevMiddleware =
       const render = (async (opts: RendererOptions) => {
         return await renderer(opts as any);
       }) as Render;
-      const { router, staticFile, notFound } = createQwikRouter({ render });
+      const { router, staticFile, notFound } = createQwikRouter({
+        render,
+        // inject the platform from dev middleware options
+        platform: ctx.opts.platform,
+      } as any);
 
       // Wrap the response to enable HTML transformation
       const wrappedRes = wrapResponseForHtmlTransform(req, res, server);
diff --git a/packages/qwik-router/src/middleware/node/index.ts b/packages/qwik-router/src/middleware/node/index.ts
index ce63c6a5ed5..d0cca053721 100644
--- a/packages/qwik-router/src/middleware/node/index.ts
+++ b/packages/qwik-router/src/middleware/node/index.ts
@@ -1,3 +1,4 @@
+import { isDev } from '@qwik.dev/core';
 import { setServerPlatform } from '@qwik.dev/core/server';
 import type { ClientConn, ServerRenderOptions } from '@qwik.dev/router/middleware/request-handler';
 import {
@@ -42,6 +43,10 @@ export function createQwikRouter(opts: QwikRouterNodeRequestOptions | QwikCityNo
         'server',
         opts.getClientConn
       );
+      // In dev mode, inject platform from options via secret property
+      if (isDev && (opts as any).platform) {
+        Object.assign(serverRequestEv.platform, (opts as any).platform);
+      }
       const handled = await requestHandler(serverRequestEv, opts);
       if (handled) {
         const err = await handled.completion;