---
title: "@dualmark/sveltekit"
description: SvelteKit adapter -- Vite route generator, handle hook, llms.txt.
---

<Tabs items={["bun", "npm", "yarn"]}>
<Tab value="bun">
```bash
bun add @dualmark/sveltekit @dualmark/core @dualmark/converters
```
</Tab>
<Tab value="npm">
```bash
npm install @dualmark/sveltekit @dualmark/core @dualmark/converters
```
</Tab>
<Tab value="yarn">
```bash
yarn add @dualmark/sveltekit @dualmark/core @dualmark/converters
```
</Tab>
</Tabs>

## `dualmark(config)`

The default export is a Vite plugin factory. Add it **before** `@sveltejs/kit/vite` in your plugin list.

```ts title="vite.config.ts"
import { sveltekit } from "@sveltejs/kit/vite";
import { defineConfig } from "vite";
import dualmark from "@dualmark/sveltekit";
import dualmarkConfig from "./src/dualmark.config";

export default defineConfig({
  plugins: [dualmark(dualmarkConfig), sveltekit()],
});
```

During Vite's `buildStart` (dev and production builds), the plugin writes generated `+server.ts` files into `src/routes`. Generated files start with a fixed header comment -- **do not copy that header into hand-written routes**, or Dualmark may delete them when your config changes.

## `createDualmarkHandle(config)`

Returns a SvelteKit `Handle` function for `hooks.server.ts`.

```ts title="src/hooks.server.ts"
import { createDualmarkHandle } from "@dualmark/sveltekit";
import dualmarkConfig from "./dualmark.config";

export const handle = createDualmarkHandle(dualmarkConfig);
```

The handle:

- Passes through direct `.md` and `/llms.txt` requests to generated route handlers
- Detects 24 known AI bot User-Agents and serves the markdown twin via internal fetch
- Honors `Accept: text/markdown` per RFC 7231
- Returns `406 Not Acceptable` when the request explicitly excludes both `text/html` and `text/markdown`
- Adds `Link: <...>; rel="alternate"; type="text/markdown"` and `Vary: Accept` to HTML responses

Compose with existing hooks via SvelteKit's `sequence` helper.

## Config

```ts
interface DualmarkSvelteKitConfig {
  siteUrl: string;

  /** Path from project root for generated routes to import. Default: src/dualmark.config.ts */
  configPath?: string;

  /** SvelteKit routes directory from project root. Default: src/routes */
  routesDir?: string;

  collections?: Record<string, CollectionConfig>;

  staticPages?: StaticPageConfig[];

  parameterizedRoutes?: ParameterizedRouteConfig[];

  llmsTxt?: {
    enabled?: boolean;
    brandName?: string;
    description?: string;
    sections?: LlmsTxtSection[];
  };

  middleware?: {
    injectLinkHeader?: boolean;
    skipPaths?: ReadonlyArray<string>;
  };

  /** Matches SvelteKit kit.appDir (default _app). Skips negotiation on internal asset paths. */
  appDir?: string;

  headers?: {
    cacheControl?: string;
    noindex?: boolean;
  };
}
```

## Collections

```ts
collections: {
  posts: {
    converter: "blog" | "case-study" | "changelog" | "compare" | "docs"
              | "feature" | "glossary" | "integration" | "legal" | "pricing" | "pseo"
              | "status-page" | "tool" | "video"
              | ((entry) => string),

    route?: string,              // URL prefix; defaults to collection key
    slugStrategy?: "single" | "catch-all",

    getEntries: () => Entry[] | Promise<Entry[]>,

    filter?: (entry) => boolean,
    sort?: (a, b) => number,

    listingMetadata?: { title: string; description: string },
    emitListing?: boolean,
  },
}
```

For each collection, the plugin generates:

- `/<route>/<slug>.md/+server.ts` for every entry
- `/<route>.md/+server.ts` for the listing (when enabled)

## Static pages

```ts
staticPages: [
  { pattern: "/", render: () => "# Home\n\nWelcome." },
  { pattern: "/about", render: () => "# About" },
],
```

Generates route handlers for `/index.md` and `/about.md`.

## Parameterized routes

```ts
parameterizedRoutes: [
  {
    pattern: "/tax/[country]",
    getStaticPaths: async () => [
      { params: { country: "us" } },
      { params: { country: "uk" } },
    ],
    render: ({ country }) => `# Tax in ${country.toUpperCase()}\n\n...`,
  },
],
```

Generates `/tax/us.md` and `/tax/uk.md`. Supported param syntax: `[name]` and `[...name]` (SvelteKit matchers like `[slug=string]` and optional `[[slug]]` are not supported).

## llms.txt

When `llmsTxt.enabled` is `true`, generates `/llms.txt/+server.ts`.

```ts
llmsTxt: {
  enabled: true,
  brandName: "Acme",
  description: "Acme's docs and blog.",
  sections: [
    {
      title: "Pages",
      links: [
        { title: "Home", href: "https://example.com/" },
        { title: "Posts", href: "https://example.com/posts" },
      ],
    },
  ],
}
```

## Programmatic API

```ts
import {
  dualmarkSvelteKit,
  createDualmarkHandle,
  createDualmarkRouteHandler,
  createLlmsTxtHandler,
  resolveConfig,
  resolveBuiltInConverter,
  DualmarkConfigError,
} from "@dualmark/sveltekit";
```

- `dualmarkSvelteKit(config)` -- Vite plugin (also exported as `dualmark` and default)
- `createDualmarkHandle(config)` -- SvelteKit handle hook
- `createDualmarkRouteHandler(config)` -- markdown twin handler (used by generated routes)
- `createLlmsTxtHandler(config)` -- llms.txt handler (used by generated routes)
- `resolveConfig(input)` -- validate + normalize config (throws `DualmarkConfigError` on invalid input)
- `resolveBuiltInConverter({ name, collectionName, baseConfig, basePath? })` -- get a converter by name