How does Remix optimize performance with headers and caching?

Remix provides the headers export for controlling HTTP cache headers on routes. export function headers({ loaderHeaders, parentHeaders }) { return { "Cache-Control": "max-age=300, stale-while-revalidate=604800" }; }. This enables aggressive CDN caching for routes with cacheable data. Cache-Control strategies: immutable static pages: max-age=31536000, immutable. Cacheable dynamic: max-age=60, s-maxage=3600, stale-while-revalidate. Never cache (auth required): no-store. Vary header: Vary: Cookie, Accept-Language for per-user/language caching. CDN edge caching: deploy Remix on Cloudflare Workers — loaders run at the edge closest to users. Cache loader responses in env.KV_NAMESPACE. Streaming: use defer to stream slow data, letting the browser receive and render fast content immediately. Resource hints: the links export can add <link rel="preload"> for critical resources. Remix's standard HTTP cache model is simpler than Next.js's multi-layer caching but well-understood and works with any CDN.