SSR

Svelte Scoped Props runs before Svelte compiles the component. That means literal scoped props are present in the server-rendered HTML.

<ChildCard scoped:class="parent-owned" />

<ChildCard scoped:class="parent-owned" />

is compiled as if the parent wrote:

<ChildCard class="parent-owned svelte-abc123" />

<ChildCard class="parent-owned svelte-abc123" />

There is no client effect that waits for hydration to add the parent scope hash. The server and client compile from the same transformed source.

Dynamic values

Dynamic values use the runtime helper on both server and client.

<ChildCard scoped:class={['parent-owned', { active }]} />

<ChildCard scoped:class={['parent-owned', { active }]} />

The helper is pure string normalization. It does not read the DOM, start observers, or wait for the browser.

Test route

The package includes a visual SvelteKit test page at /tests/scoped-props and an SSR check route at /tests/scoped-props/ssr-check. Those routes are intentionally test fixtures, not marketing docs.