Svelte Web Components and SvelteKit SSR — @awc-ui/svelte

@awc-ui/svelte supplies types for AWC UI's native custom elements in Svelte 5.57 or later. Property types and custom-event payloads come from the core declarations.

npm install @awc-ui/svelte @awc-ui/core

For a client-rendered Vite application, load the theme and register the components you use through static imports. Import the Svelte package's types once:

// main.ts
import type {} from '@awc-ui/svelte';
import '@awc-ui/core/css/tokens.css';
import '@awc-ui/core/components/md-text-field';
import '@awc-ui/core/components/md-button';

Then use the native properties and custom events directly:

<script lang="ts">
  let name = '';
</script>

<md-text-field
  label="Project name"
  value={name}
  on:mdInput={(event) => name = event.detail}
></md-text-field>
<md-button variant="filled">Create project</md-button>

The mdInput payload is inferred as a string, and invalid component property values are reported by svelte-check. Svelte 5 also supports the event-handler property spelling onmdInput. Use value plus the component's mdInput or mdChange event to synchronize forms; the custom elements do not expose a Svelte bind:value contract.

defineCustomElements remains available from @awc-ui/svelte for applications that deliberately deploy the lazy loader and its runtime chunks. Static component imports work with Vite's module graph and keep registration limited to the components you use.

SvelteKit server-side rendering

Use SvelteKit 2.70.3 or later for the client initialization hook. On the server, transform the completed HTML response with renderToString from @awc-ui/core/hydrate; createPageTransform from @awc-ui/core/ssr/sveltekit buffers response chunks until the document is complete.

On the client, create a shared createSvelteHydration() instance from @awc-ui/core/ssr/sveltekit. Call capture() from hooks.client.ts's init before Svelte hydrates, then call restore() in the root layout's onMount before dynamically importing the SSR-capable component entries. This preserves AWC shadow roots while Svelte claims the surrounding document.

The helper must come from the same AWC UI release as the core components. Follow the complete SvelteKit reference app and shared SSR guide for the server hook and client lifecycle.