Getting Started

The headless libraries give you the engine and the plugin system — you own every pixel of the UI. An app depends on two packages: the adapter for your framework, and an engine.

Installation#

npm install @embedpdf/svelte @embedpdf/engine

The Svelte adapter mirrors the React surface subpath-for-subpath — the same verticals, exposed as components and stores.

Your first viewer#

localEngine() creates the engine — synchronously, allocating nothing until first use, so a module-scope const engine = localEngine() is safe (even under SSR). Hand it to <Viewer>: the viewer warms it up on mount and PDFium boots in a worker in the background, so the stage and render layer draw the pages the moment a document is ready — no worker wiring, no lifecycle to manage. This is the whole app:

Loading live preview…

<script lang="ts">
  import { onMount } from 'svelte';
  import type { LocalEngine } from '@embedpdf/engine';
  import PdfPage from './PdfPage.svelte';

  // The Svelte adapter is in progress — this drives the framework-free engine
  // directly: App owns the engine and the document, PdfPage renders one page.
  type PdfDocument = Awaited<ReturnType<LocalEngine['open']>>;

  let doc = $state<PdfDocument>();
  let status = $state('Booting engine…');

  onMount(async () => {
    // `localEngine()` IS the engine — no worker wiring needed; PDFium boots in
    // a worker on first use. The Svelte adapter will own this for you.
    const { localEngine } = await import('@embedpdf/engine');
    const engine = localEngine();

    status = 'Opening document…';
    const response = await fetch('https://snippet.embedpdf.com/ebook.pdf');
    const bytes = new Uint8Array(await response.arrayBuffer());
    doc = await engine.open({ kind: 'bytes', id: 'ebook', bytes });
  });
</script>

{#if doc}
  <PdfPage {doc} pageNumber={1} />
{:else}
  <p>{status}</p>
{/if}

Prefer the viewer to own the engine’s lifetime — created on mount, destroyed on unmount? Pass a thunk instead: engine={() => localEngine()}. See the Engine getting started for the ownership model, fallback fonts, cloud, and SSR.

Was this page helpful?

Your feedback goes directly to the documentation team.