Incremental Static Regeneration (ISR)
A hybrid: the page is generated as static HTML, then transparently rebuilt in the background at a fixed interval (here, 10 seconds). Static speed, with content that stays reasonably fresh without a redeploy.
Expected behaviour
The timestamp shows when the page was last generated. Refresh within 10 seconds and it stays the same, because the cached copy is still valid. After 10 seconds, the next request triggers a background rebuild, and a new timestamp appears on the request after that.
How this page works
- 1The page is generated once at build time.
- 2Next.js caches the static HTML and serves it instantly.
- 3After 10 seconds, the cached version becomes stale.
- 4The next request triggers a background regeneration.
- 5Once regenerated, everyone sees the updated page.
Live result
Page generated at
2026-10-15T20:47:54.290Z
Refresh a few times, more than 10 seconds apart.