Cache tags, soft-stale ISR, and after()

Purge by cache tag across the edge CDN, Runtime Cache, and Incremental Static Regeneration (ISR) together. Next.js revalidateTag, revalidatePath, and after() follow the same multi-layer model as Vercel.

Tag once, expire everywhere

Attach the same tag string to CDN responses (Cache-Tag) and Runtime Cache writes. When you call revalidateTag or expireTag, Easel updates the shared tag clock, marks matching ISR pages soft-stale, clears tagged Runtime Cache entries when you expire them, and purges matching edge objects for the deployment.

Schedule work after the response

Schedule revalidation after you return:

import { after } from "next/server";
import { revalidateTag } from "next/cache";

export async function POST() {
  after(() => {
    revalidateTag("products");
  });
  return Response.json({ ok: true });
}

The response goes out first. Tag expiry runs in the background for that request. See Invalidate and revalidate cached content and Runtime Cache.