States the framework's identity clearly: Start is built on TanStack Router + Vite, not Next.js — no getServerSideProps, no "use server" directives, no app/layout.tsx. Routes live in src/routes/, server-only code uses createServerFn, code is isomorphic by default (loaders run on both server and client), and types are fully inferred (never cast or annotate inferred values).

Documents the two hand-written wiring files every app needs (src/router.tsx, src/routes/__root.tsx) plus the one generated file that must never be edited (routeTree.gen.ts), a minimal Vite config, and the CLI scaffolding shortcut.

Do NOT use this skill for server-only vs isomorphic execution boundaries in depth (use start-execution-model), for SOLID/code organization (use solid-tanstack-start), or for a plain React SPA without Start.

TanStack Start Core

TanStack Start is a full-stack React framework built on TanStack Router + Vite (Rsbuild also supported). It adds SSR, streaming, server functions (type-safe RPCs), middleware, and universal deployment. This skill targets @tanstack/react-start v1.166.2.