What problem does it solve? Building React applications with routing often leads to runtime errors from untyped route params, scattered data-fetching logic in useEffect hooks, and fragile search parameter handling. This Skill provides the patterns and APIs to implement fully type-safe routing with TanStack Router, covering route trees, loaders, search validation, and navigation. ## Core Features & Use Cases - File-Based and Code-Based Routing: Define routes via file conventions (dynamic $param, pathless _layout, splat routes) or programmatic route trees with automatic type generation. - Type-Safe Data Loading: Use route loaders with loaderDeps, staleTime, deferred streaming via defer/Await, and TanStack Query integration through router context. - Search Param Validation & Navigation: Validate URL search params with Zod schemas, navigate with typed Link components or useNavigate, and guard routes with beforeLoad redirects. - Use Case: Build a dashboard where the posts list page validates ?page and ?filter search params, preloads data on link hover, blocks navigation away from dirty forms, and redirects unauthenticated users to login. ## Quick Start Ask the AI to set up TanStack Router in your React app with file-based routing, a posts route with a loader, and validated search parameters.