Getting started

6-9 minutes read
By Titus Wormer

Getting started

This article explains how to integrate MDX into your project. It shows how to use MDX with your bundler and JSX runtime of choice. To understand how the MDX format works, we recommend that you start with § What is MDX. See § Using MDX when you’re all set up and ready to use MDX.

Prerequisites
Quick start
Integrations
Further reading

Prerequisites

MDX relies on JSX, so it’s required that your project supports JSX as well. Any JSX runtime (React, Preact, Vue, etc.) will do. Note that we do compile JSX to JavaScript for you so you don’t have to set that up.

All @mdx-js/* packages are written in modern JavaScript. A Node.js version of 16.0 or later is needed to use them. Our packages are also ESM only, so they have to be imported instead of required.

Note: Using Rust instead of Node.js? Try mdxjs-rs!

Quick start

Bundler

MDX is a language that’s compiled to JavaScript. (We also compile regular markdown to JavaScript.) The easiest way to get started is to use an integration for your bundler if you have one:

if you use esbuild, install and configure @mdx-js/esbuild
if you use Rollup (or Vite), install and configure @mdx-js/rollup
if you use webpack (or Next.js), install and configure @mdx-js/loader

You can also use MDX without bundlers:

you can import MDX files in Node.js with @mdx-js/node-loader
you can use our core compiler @mdx-js/mdx to compile MDX files
you can use our core compiler @mdx-js/mdx to evaluate (compile and run) MDX files

For more info on these tools, see their dedicated sections: ¶ Next.js, ¶ Node.js, ¶ Rollup, ¶ Vite, ¶ esbuild, and ¶ webpack.

JSX

Now you’ve set up an integration or @mdx-js/mdx itself, it’s time to configure your JSX runtime.

if you use React, that’s the default; optionally install and configure @mdx-js/react
if you use Preact, set jsxImportSource in ProcessorOptions to 'preact'; optionally install and configure @mdx-js/preact
if you use Svelte, install svelte-jsx, and set jsxImportSource in ProcessorOptions to 'svelte-jsx'
if you use Vue, set jsxImportSource in ProcessorOptions to 'vue'; optionally install and configure @mdx-js/vue
if you use Solid, set jsxImportSource in ProcessorOptions to 'solid-js/h'
if you use Emotion, set jsxImportSource in ProcessorOptions to '@emotion/react'
if you use Theme UI, install and configure @mdx-js/react, then wrap your MDX content in a <ThemeProvider />

Other JSX runtimes are supported by setting jsxImportSource in ProcessorOptions.

For more info on these tools, see their dedicated sections: ¶ Emotion, ¶ Preact, ¶ React, ¶ Solid, ¶ Svelte, ¶ Theme UI, and ¶ Vue.

Editor

You can enhance the experience of using MDX by adding support of it to your editor:

if you use VS Code, try mdx-js/vscode-mdx
if you use Vim, try jxnblk/vim-mdx-js
if you use Sublime Text, try jonsuh/mdx-sublime
if you use JetBrains IntelliJ/WebStorm, try JetBrains/mdx-intellij-plugin

The syntax highlighting that powers our VS Code extension and that is used to highlight code blocks on GitHub is maintained at wooorm/markdown-tm-language.

Types

Expand example of typed imports

First install the package:

Shell

npm install @types/mdx

…TypeScript should automatically pick it up:

example.js

import Post from './post.mdx' // `Post` is now typed.

Our packages are typed with TypeScript. For types to work, the JSX namespace must be typed. This is done by installing and using the types of your framework, such as @types/react.

To enable types for imported .mdx, .md, etc., install and use @types/mdx. This package also exports several useful types, such as MDXComponents which represents the components prop. You can import them like so:

example.ts

import type {MDXComponents} from 'mdx/types.js'

Security

MDX is a programming language. If you trust your authors, that’s fine. If you don’t, it’s unsafe.

Do not let random people from the internet write MDX. If you do, you might want to look into using <iframe>s with sandbox, but security is hard, and that doesn’t seem to be 100%. For Node.js, vm2 sounds interesting. But you should probably also sandbox the whole OS using Docker or similar, perform rate limiting, and make sure processes can be killed when taking too long.

Integrations

Bundlers

esbuild

Expand example

example.js

import mdx from '@mdx-js/esbuild'
import esbuild from 'esbuild'

await esbuild.build({
  entryPoints: ['index.mdx'],
  format: 'esm',
  outfile: 'output.js',
  plugins: [mdx({/* jsxImportSource: …, otherOptions… */})]
})

We support esbuild. Install and configure the esbuild plugin @mdx-js/esbuild. Configure your JSX runtime depending on which one (React, Preact, Vue, etc.) you use.

To use more modern JavaScript features than what your users support, configure esbuild’s target.

Rollup

Expand example

rollup.config.js

import mdx from '@mdx-js/rollup'
import {babel} from '@rollup/plugin-babel'

/** @type {import('rollup').RollupOptions} */
const config = {
  // …
  plugins: [
    // …
    mdx({/* jsxImportSource: …, otherOptions… */})
    // Babel is optional:
    babel({
      // Also run on what used to be `.mdx` (but is now JS):
      extensions: ['.js', '.jsx', '.cjs', '.mjs', '.md', '.mdx'],
      // Other options…
    })
  ]
}

export default config

We support Rollup. Install and configure the Rollup plugin @mdx-js/rollup. Configure your JSX runtime depending on which one (React, Preact, Vue, etc.) you use.

To use more modern JavaScript features than what your users support, install and configure @rollup/plugin-babel.

See also ¶ Vite, if you use Rollup through it, for more info.

Webpack

Expand example

webpack.config.js

/** @type {import('webpack').Configuration} */
const webpackConfig = {
  module: {
    // …
    rules: [
      // …
      {
        test: /\.mdx?$/,
        use: [
          // Babel is optional:
          {loader: 'babel-loader', options: {}},
          {
            loader: '@mdx-js/loader',
            /** @type {import('@mdx-js/loader').Options} */
            options: {/* jsxImportSource: …, otherOptions… */}
          }
        ]
      }
    ]
  }
}

export default webpackConfig

We support webpack. Install and configure the webpack loader @mdx-js/loader. Configure your JSX runtime depending on which one (React, Preact, Vue, etc.) you use.

To use more modern JavaScript features than what your users support, install and configure babel-loader.

See also ¶ Next.js, if you use webpack through it, for more info.

Build systems

Vite

Expand example

vite.config.js

import mdx from '@mdx-js/rollup'
import {defineConfig} from 'vite'

const viteConfig = defineConfig({
  plugins: [
    mdx(/* jsxImportSource: …, otherOptions… */)
  ]
})

export default viteConfig

We support Vite. Install and configure the Rollup plugin @mdx-js/rollup. Configure your JSX runtime depending on which one (React, Preact, Vue, etc.) you use.

To use more modern JavaScript features than what your users support, configure Vite’s build.target.

Note: If you also use vitejs/vite-plugin-react, you must force @mdx-js/rollup to run in the pre phase before it:

vite.config.js

// …
const viteConfig = defineConfig({
  plugins: [
    {enforce: 'pre', ...mdx(/* jsxImportSource: …, otherOptions… */)},
    react()
  ]
})
// …

See also ¶ Rollup which is used in Vite and see ¶ Vue if you’re using that, for more info.

Compilers

Babel

Expand plugin and sample use

This plugin:

plugin.js

import path from 'node:path'
import parser from '@babel/parser'
import {compileSync} from '@mdx-js/mdx'
import estreeToBabel from 'estree-to-babel'

export function babelPluginSyntaxMdx() {
  // Tell Babel to use a different parser.
  return {parserOverride: babelParserWithMdx}
}

// A Babel parser that parses MDX files with `@mdx-js/mdx` and passes any
// other things through to the normal Babel parser.
function babelParserWithMdx(value, options) {
  if (options.sourceFileName && /\.mdx?$/.test(options.sourceFileName)) {
    // Babel does not support async parsers, unfortunately.
    return compileSync(
      {value, path: options.sourceFileName},
      // Tell `@mdx-js/mdx` to return a Babel tree instead of serialized JS.
      {recmaPlugins: [recmaBabel], /* jsxImportSource: …, otherOptions… */}
    ).result
  }

  return parser.parse(value, options)
}

// A “recma” plugin is a unified plugin that runs on the estree (used by
// `@mdx-js/mdx` and much of the JS ecosystem but not Babel).
// This plugin defines `'estree-to-babel'` as the compiler,
// which means that the resulting Babel tree is given back by `compileSync`.
function recmaBabel() {
  this.compiler = estreeToBabel
}

…can be used like so with the Babel API:

example.js

import babel from '@babel/core'
import {babelPluginSyntaxMdx} from './plugin.js'

// Note that a filename must be set for our plugin to know it’s MDX instead of JS.
await babel.transformAsync(file, {filename: 'example.mdx', plugins: [babelPluginSyntaxMdx]})

You should probably use Rollup or webpack instead of Babel directly as that gives the best interface. It is possible to use @mdx-js/mdx in Babel and it’s a bit faster, as it skips @mdx-js/mdx serialization and Babel parsing, if Babel is used anyway.

Babel does not support syntax extensions to its parser (it has “syntax” plugins but those only turn internal flags on or off). It does support setting a different parser. Which in turn lets us choose whether to use the @mdx-js/mdx or @babel/parser.

Site generators

Astro

Astro has its own MDX integration. You can add the integration with the Astro CLI: npx astro add mdx.

This base setup lets you import markdown, Astro components, and MDX files as components. See Astro’s Framework components guide for info on how to use components from frameworks in your MDX files.

For more on how to combine Astro and MDX, see Astro’s MDX integration docs.

Docusaurus

Docusaurus supports MDX by default. See Docusaurus’ MDX and React guide for info on how to use MDX with Docusaurus.

Gatsby

Gatsby has its own plugin to support MDX. See gatsby-plugin-mdx on how to use MDX with Gatsby.

Next.js

Expand example

next.config.js

import nextMdx from '@next/mdx'

const withMdx = nextMdx({
  // By default only the `.mdx` extension is supported.
  extension: /\.mdx?$/,
  options: {/* otherOptions… */}
})

const nextConfig = withMdx({
  // Support MDX files as pages:
  pageExtensions: ['md', 'mdx', 'tsx', 'ts', 'jsx', 'js'],
})

export default nextConfig

Next.js has its own MDX integration. Install and configure @next/mdx.

Do not use providerImportSource and @mdx-js/react with Next to inject components. Add an mdx-components.tsx (in src/ or /) file instead. See Configuring MDX on nextjs.org for more info.

Parcel

Parcel has its own plugin to support MDX. See @parcel/transformer-mdx on how to use MDX with Parcel.

JSX runtimes

Emotion

Expand example

example.js

import {compile} from '@mdx-js/mdx'

const js = String(await compile('# hi', {jsxImportSource: '@emotion/react', /* otherOptions… */}))

Emotion is supported when jsxImportSource in ProcessorOptions is set to '@emotion/react'. You can optionally install and configure @mdx-js/react to support context based component passing.

See also ¶ React, which is used in Emotion, and see ¶ Rollup and ¶ webpack, which you might be using, for more info.

Ink

Expand example

example.mdx

# Hi!

example.js

import React from 'react'
import {Text, render} from 'ink'
import Content from './example.mdx' // Assumes an integration is used to compile MDX -> JS.

const components = {
  h1(props) {
    return React.createElement(Text, {bold: true, ...props})
  },
  p: Text
}

render(React.createElement(Content, {components}))

Can be used with:

Shell

node --loader=@mdx-js/node-loader example.js

Ink uses the React JSX runtime, so set that up. You will need to swap HTML elements out for Ink’s components. See § Table of components for what those are and Ink’s docs on what they can be replaced with.

See also ¶ Node.js and ¶ React for more info.

Preact

Expand example

example.js

import {compile} from '@mdx-js/mdx'

const js = String(await compile('# hi', {jsxImportSource: 'preact', /* otherOptions… */}))

Preact is supported when jsxImportSource in ProcessorOptions is set to 'preact'. You can optionally install and configure @mdx-js/preact to support context based component passing.

See also ¶ Rollup, ¶ esbuild, and ¶ webpack, which you might be using, for more info.

React

React is supported by default. You can optionally install and configure @mdx-js/react to support context based component passing.

See also ¶ Rollup, ¶ esbuild, and ¶ webpack, which you might be using, for more info.

Theme UI

Expand example

Example w/o @mdx-js/react

example.js

import {base} from '@theme-ui/preset-base'
import {ThemeProvider, components} from 'theme-ui'
import Post from './post.mdx' // Assumes an integration is used to compile MDX -> JS.

<ThemeProvider theme={base}>
  <Post components={components} />
</ThemeProvider>

Example w/ @mdx-js/react

example.js

import {base} from '@theme-ui/preset-base'
import {ThemeProvider} from 'theme-ui'
import Post from './post.mdx' // Assumes an integration is used to compile MDX -> JS.

<ThemeProvider theme={base}>
  <Post />
</ThemeProvider>

Theme UI is a React-specific library that depends on context to access its effective components. You can install and configure @mdx-js/react to support context based component passing.

See also ¶ Emotion, ¶ React, ¶ Rollup, and ¶ esbuild, ¶ webpack, which you might be using, for more info.

Svelte

Expand example

example.js

import {compile} from '@mdx-js/mdx'

const js = String(await compile('# hi', {jsxImportSource: 'svelte-jsx', /* otherOptions… */}))

Svelte is supported when jsxImportSource in ProcessorOptions is set to 'svelte-jsx'.

See also ¶ Rollup, ¶ esbuild, and ¶ webpack, which you might be using, for more info.

Vue

Expand example

example.js

import {compile} from '@mdx-js/mdx'

const js = String(await compile('# hi', {jsxImportSource: 'vue', /* otherOptions… */}))

Vue is supported when jsxImportSource in ProcessorOptions is set to 'vue'. You can optionally install and configure @mdx-js/vue to support context based component passing.

See also ¶ Vite, which you might be using, for more info.

Solid

Expand example

example.js

import {compile} from '@mdx-js/mdx'

const js = String(await compile('# hi', {jsxImportSource: 'solid-js/h', /* otherOptions… */}))

Solid is supported when jsxImportSource in ProcessorOptions is set to 'solid-js/h'.

See also ¶ Rollup and ¶ Vite, which you might be using, for more info.

JavaScript engines

Node.js

MDX files can be imported in Node by using @mdx-js/node-loader. See its readme on how to configure it.

Getting started

Contents

Prerequisites

Quick start

Bundler

JSX

Editor

Types

Security

Integrations

Bundlers

esbuild

Rollup

Webpack

Build systems

Vite

Compilers

Babel

Site generators

Astro

Docusaurus

Gatsby

Next.js

Parcel

JSX runtimes

Emotion

Ink

Preact

React

Theme UI

Svelte

Vue

Solid

JavaScript engines

Node.js

Further reading