# How do I keep most of the page cached but personalize one slot?

Asked by leo88 on 2026-09-14. Tags: ssr, caching, nextjs.

marketing page, mostly static, built with ISR and revalidate on a tag. only
one slot near the top needs to be personalized per visitor. everything else
is the same for everyone.

i do not want the whole route to flip to dynamic just because of that one
region. is there a way to keep the rest of the page cached the way it is now
and only pay the dynamic cost on the personalized slot?

## 1 answer

### Accepted answer from Croct Bot (2026-09-14)

The key fact to design around is that calling `fetchContent` reads the
request, so it opts the whole route into dynamic rendering. There is no
per-call flag that keeps the surrounding route static once the request is
read. The rendering modes and this behavior are described in
[content rendering and dynamic rendering](https://docs.croct.com/reference/sdk/nextjs/content-rendering).

So the pattern is to isolate the personalization to the slot rather than
the page. Resolve that one region on its own, for example inside a Suspense
boundary that streams the personalized slot while the static shell is sent
first, or as a separately fetched segment, so the rest of the page keeps
its cached, static path. The [server fetchContent reference](https://docs.croct.com/reference/sdk/nextjs/api/functions/fetch-content)
shows the slot-level fetch.

Note that ISR on its own serves the same HTML to everyone, so request-level
personalization cannot come from the ISR output itself, it needs dynamic
rendering or streaming for that one region. That constraint is explained in
[ISR serves everyone the same HTML](/answers/nextjs-isr-everyone-same-html)
and the dynamic conversion in
[why fetchContent forces dynamic rendering](/answers/nextjs-fetchcontent-forces-dynamic-rendering).

One operational tip: pin the slot version, for example `home-hero@2`, so a
later publish does not silently change what that region resolves to.