Lazy Islands
You can mark islands with mochi:hydrate:visible so each one fetches its JS and CSS only when it scrolls into view, via an IntersectionObserver. Lazy islands also have the benefit of not loading their CSS until they come into view, great for secondary content far down the page.
Lazy Island #1
#1 Waiting to hydrate...
Lazy Island #2
#2 Waiting to hydrate...
Lazy Island #3
#3 Waiting to hydrate...
Lazy Island #4
#4 Waiting to hydrate...
Lazy Island #5
#5 Waiting to hydrate...
Lazy Island #6
#6 Waiting to hydrate...
<script>
import LazyDemo from './LazyDemo.svelte';
</script>
<div class="stack">
{#each Array(6) as _, i (i)}
<div class="item">
<h3>Lazy Island #{i + 1}</h3>
<LazyDemo mochi:hydrate:visible index={i + 1} />
</div>
{/each}
</div>
Styles
<style>
.stack {
display: flex;
flex-direction: column;
gap: 1.5rem;
}
.item h3 {
font-size: 0.95rem;
font-weight: 600;
color: var(--text-muted);
margin-bottom: 0.5rem;
}
</style>
More demos
Captcha How the captcha works — slide-to-verify backed by a hash chain and proof-of-work, with no third party and no tracking. isHydratable() How isHydratable() works — detect from any depth whether the current subtree will hydrate, for SSR-only fallbacks without prop forwarding. Image: Events How image events work — subscribe to image:store / image:delete on mochiEvents to mirror the <Image> cache to durable storage like S3.