Tanstack Start

Setup

Installation

npm i fumadocs-mdx fumadocs-core @types/mdx

Create the configuration file:

source.config.ts

import { defineConfig, defineDocs } from 'fumadocs-mdx/config';

export const docs = defineDocs({
  dir: 'content/docs',
});

export default defineConfig();

Add the Vite plugin:

vite.config.ts

import react from '@vitejs/plugin-react';
import { tanstackStart } from '@tanstack/react-start/plugin/vite';
import { defineConfig } from 'vite';
import tsConfigPaths from 'vite-tsconfig-paths';
import tailwindcss from '@tailwindcss/vite';
import mdx from 'fumadocs-mdx/vite';

export default defineConfig({
  server: {
    port: 3000,
  },
  plugins: [
    mdx(await import('./source.config')),
    tailwindcss(),
    tsConfigPaths({
      projects: ['./tsconfig.json'],
    }),
    tanstackStart({
      prerender: {
        enabled: true,
      },
    }),
    react(),
  ],
});

Integrate with Fumadocs

To integrate with Fumadocs, create a lib/source.ts file:

src/lib/source.ts

import { loader } from 'fumadocs-core/source';
import { create, docs } from '../../source.generated';

export const source = loader({
  source: await create.sourceAsync(docs.doc, docs.meta),
  baseUrl: '/docs',
});

The source.generated.ts file will be generated when you run development server or production build.

Done

You can now write content in content/docs folder.

Examples

Rendering Content

As Tanstack Start doesn't support RSC at the moment, use createClientLoader() to lazy load MDX content as a component on browser.

For example:

src/routes/docs/$.tsx

import { createFileRoute, notFound } from '@tanstack/react-router';
import { createServerFn } from '@tanstack/react-start';
import { source } from '@/lib/source';
import { docs } from '../../../source.generated';
import { createClientLoader } from 'fumadocs-mdx/runtime/vite';

export const Route = createFileRoute('/docs/$')({
  component: Page,
  loader: async ({ params }) => {
    const data = await loader({ data: params._splat?.split('/') ?? [] });
    await clientLoader.preload(data.path);
    return data;
  },
});

const loader = createServerFn({
  method: 'GET',
})
  .inputValidator((slugs: string[]) => slugs)
  .handler(async ({ data: slugs }) => {
    const page = source.getPage(slugs);
    if (!page) throw notFound();

    return {
      path: page.path,
    };
  });

const clientLoader = createClientLoader(docs.doc, {
  id: 'docs',
  component({ frontmatter, default: MDX }) {
    return (
      <div className="prose">
        <h1>{frontmatter.title}</h1>
        <MDX />
      </div>
    );
  },
});

function Page() {
  const data = Route.useLoaderData();
  const Content = clientLoader.getComponent(data.path);

  return <Content />;
}

As you see, the source.generated.ts file can be imported directly:

import { docs } from './source.generated';
console.log(docs);