Next.js: Route handlers (API) — как это работает на практике

Question

Accepted Answer

Handler на server (Node default или `runtime = 'edge'`). Next augments `Request` → `NextRequest`; responses — `NextResponse` helpers.

## Разбор

**Caching changed Next 15.** Next 14: `GET` cached by default. **Next 15: dynamic (uncached) by default.** Opt static: `export const dynamic = 'force-static'`. Non-GET never cached. Favourite interview probe — silent behaviour change on upgrade.

Dynamic segments: `app/api/posts/[id]/route.ts` получает `{ params }` (async Next 15) second argument.

## Итог

Route handlers = Web Request/Response + Next 15 GET cache flip + async params.