diff --git a/src/integrations/supabase/auth-attacher.ts b/src/integrations/supabase/auth-attacher.ts
new file mode 100644
index 0000000..5bc57b7
--- /dev/null
+++ b/src/integrations/supabase/auth-attacher.ts
@@ -0,0 +1,15 @@
+// This file is automatically generated. Do not edit it directly.
+import { createMiddleware } from '@tanstack/react-start'
+import { supabase } from './client'
+
+// Must be registered as a global `functionMiddleware` in `src/start.ts`; otherwise
+// the browser never attaches the bearer token to serverFn RPCs.
+export const attachSupabaseAuth = createMiddleware({ type: 'function' }).client(
+  async ({ next }) => {
+    const { data } = await supabase.auth.getSession()
+    const token = data.session?.access_token
+    return next({
+      headers: token ? { Authorization: `Bearer ${token}` } : {},
+    })
+  },
+)