TanStack Query and Router intro

Book 1 closes on the browser ship stack: SolidJS + TanStack Query + TanStack Router.

Three layers

Layer	Tool	Responsibility
Routes	TanStack Router	URL → page component, type-safe params
Server state	TanStack Query	fetch, cache, stale, refetchInterval
UI state	Solid signals	toggles, form focus, SSE merge into view

Animate one poll cycle in TanStackDataFlow.

Dev proxy

Radar dev server proxies /api/* to the gateway — same-origin from the browser’s perspective (lesson 0.7).

useQuery(() => ({
  queryKey: ["metrics", "summary"],
  queryFn: () => fetch("/api/metrics/summary").then((r) => r.json()),
  refetchInterval: 5000,
}));

Book 1 complete

You can read ingestion Rust and radar TypeScript. Book 2 starts with why events beat synchronous chains.

Teach-back prompt

Why keep SSE live feed separate from Query polling?