PostHog Handbook Library / Engineering

2,344 words. Estimated reading time: 11 min.

# MDX components

Auto TL;DR

## At a Glance

This long page covers these main areas. The list is generated from the article headings, so it updates with every handbook rebuild.

1. Images
2. Product screenshots
3. Image slider
4. Videos
5. Embedding Wistia videos
6. Embedding YouTube videos
7. Code blocks
8. Basic codeblock

There are some nifty MDX components available for use in Markdown content. These components are included globally, so you don't need to do anything special to use them (like renaming `.md` to `.mdx` or manually importing them at the top of the file).

### Images

#### Product screenshots

The `` component encapsulates an image with a border and background. It's useful since the app's background matches the website background, and without using this component, it can be hard to differentiate between the screenshot and normal page content. It also optionally supports dark mode screenshots.

You use it by passing image URLs to the `imageLight` and `imageDark` props like this:

    <ProductScreenshot
    imageLight="https://res.cloudinary.com/dmukukwp6/image/upload/posthog.com/contents/handbook/images/tutorials/limit-session-recordings/sampling-config-light.png"
    imageDark="https://res.cloudinary.com/dmukukwp6/image/upload/posthog.com/contents/handbook/images/tutorials/limit-session-recordings/sampling-config-dark.png"
    alt="Sampling config shown set to 100% i.e. no sampling"
    classes="rounded"
    />

Optionally pass `zoom={false}` if you don't want the image to be zoomable, otherwise it will be zoomable by default.

_Note: If you don't have a dark image, just leave out the `imageDark` prop and the light screenshot will be used for both color modes._

#### Image slider

You can create a slider or carousel of images by wrapping them in the `<ImageSlider>` component like this:

    ![posthog](https://res.cloudinary.com/dmukukwp6/image/upload/v1710055416/posthog.com/contents/images/screenshots/hogflix-dashboard.png)
    ![posthog](https://res.cloudinary.com/dmukukwp6/image/upload/v1710055416/posthog.com/contents/images/screenshots/hogflix-dashboard.png)

See an example in our open-source analytics tools post.

### Videos

Th `` component works the same as product screenshots (above) for videos uploaded to Cloudinary but supports light and dark videos.

1. Import the video(s) at the top of the post (directly following the MDX file's frontmatter and dashes):

<!-- prettier-ignore -->

    ---
    export const NewFunnelLight = "https://res.cloudinary.com/dmukukwp6/video/upload/posthog.com/contents/handbook/images/docs/user-guides/funnels/new-funnel.mp4"
    export const NewFunnelDark = "https://res.cloudinary.com/dmukukwp6/video/upload/posthog.com/contents/handbook/images/docs/user-guides/funnels/new-funnel-dark.mp4"

1. Use the component wherever you want the video(s) to appear.

<!-- prettier-ignore -->

    <ProductVideo
    videoLight={NewFunnelLight}
    videoDark={NewFunnelDark}
    classes="rounded"
    />

_Note: If you don't have a dark video, just leave out the `videoDark` prop and the light video will be used for both color modes._

#### Embedding Wistia videos

This can be used in articles like tutorials or blog posts for longer-form videos (where the asset exceeds 20 MB and can't be uploaded to Cloudinary).

#### Embedding YouTube videos

While not an MDX component, a reminder that when embedding a YouTube video, you should do two things:

1. Use the `-nocookie` variant of the YouTube URL. eg:

    https://www.youtube-nocookie.com/embed/{VIDEO_ID}

1. Add the `allowfullscreen` attribute to the iframe so users have the option to watch the video in fullscreen (useful for reading code snippets).

Example:

    <iframe
        src="https://www.youtube-nocookie.com/embed/2jQco8hEvTI?start=375"
        className="rounded shadow-xl"
    />

### Code blocks

The PostHog website has a custom code block component that comes with a number of useful features built-in:

- Syntax highlighting
- Multiple snippets in a single codeblock
- Specifying which file a snippet is from

#### Basic codeblock

Codeblocks in PostHog are created by enclosing your snippet using three backticks (\`\`\`) or three tildes (\~\~\~), as shown below:

{ "name": "Max, Hedgehog in Residence", "age": 2 }

This will produce the following codeblock:

    {
    "name": "Max, Hedgehog in Residence",
    "age": 2
    }

#### Adding syntax highlighting

Syntax highlighting can be added by specifying a language for the codeblock, which is done by appending the name of the language directly after the opening backticks or tildes as shown below.

{ "name": "Max, Hedgehog in Residence", "age": 2 }

This will produce the following output:

    {
    "name": "Max, Hedgehog in Residence",
    "age": 2
    }

#### Using tabs

You can use the `` component to create tabs in your code blocks. This is useful for showing multiple code snippets or examples in a single code block.

<Tab.Group tabs={[ 'Preview', 'Markdown']}> Preview Markdown

    console.log('Hello, world!')

console.log('Hello, world!')

##### Supported languages

Here is a list of all the languages that are supported in codeblocks:

Frontend

| | | | ----------------- | -------------- | | HTML | `html` | | CSS / SCSS / LESS | `css` / `less` | | JavaScript | `js` | | JSX | `jsx` | | TypeScript | `ts` | | TSX | `tsx` | | Swift | `swift` | | Dart | `dart` | | Objective-C | `objectivec` |

Backend

| | | | ------- | ----------- | | Node.js | `node` | | Elixir | `elixir` | | Golang | `go` | | Java | `java` | | PHP | `php` | | Ruby | `ruby` | | Python | `python` | | C / C++ | `c` / `cpp` |

Misc.

| | | | -------- | ----------------- | | Terminal | `bash` or `shell` | | JSON | `json` | | XML | `xml` | | SQL | `sql` | | GraphQL | `graphql` | | Markdown | `markdown` | | MDX | `mdx` | | YAML | `yaml` | | Git | `git` |

> Note: If you want syntax highlighting for a snippet in another language, feel free to add your language to the imports in languages.tsx and open a PR.

#### Multi-language code blocks

You can use the `<MultiLanguage>` component to show code blocks in multiple languages.

<Tab.Group tabs={[ 'Preview', 'Markdown']}> Preview Markdown

    console.log('Hello, world!')

    print('Hello, world!')

console.log('Hello, world!')

print('Hello, world!')

#### Multiple code snippets in one block

With PostHog's `MultiLanguage` component, it's possible to group multiple code snippets together into a single block.

console.log('Hello world!')

<div>Hello world!</div>

> Note: Make sure to include empty lines between all your code snippets, as well as above and below the `MultiLanguage` tag

This will render the following codeblock:

    console.log('Hello world!')

    <div>Hello world!</div>

#### Specifying which file a snippet is from

You can specify a filename that a code snippet belongs to using the `file` parameter, which will be displayed in the top bar of the block.

cloud: 'aws' ingress: hostname: <your-hostname> nginx: enabled: true cert-manager: enabled: true

> Note: Make sure not to surround your filename in quotes. Each parameter-value pair is delimited by spaces.

This produces the following codeblock:

    cloud: 'aws'
    ingress:
    hostname: <your-hostname>
    nginx:
    enabled: true
    cert-manager:
    enabled: true

#### Code highlighting

Especially in long tutorials, you can highlight the important differences between steps using highlighting comments. It's much easier to read visual diffs than reading through the code block line by line.

| Comment | Effect | Usage | | -------------- | ---------------- | ---------------------------------------- | | `// +` | Green highlight | Represents additions in diffs | | `// -` | Red highlight | Represents removals in diffs | | `// HIGHLIGHT` | Yellow highlight | General emphasis without special meaning |

<Tab.Group tabs={[ 'Preview', 'Markdown']}> Preview Markdown

    const a = 1
    const b = 2
    const c = a + b // +

    console.log(a + b) // -
    console.log(c) // +

    console.log('end') // HIGHLIGHT

const a = 1 const b = 2 const c = a + b // +

console.log(a + b) // - console.log(c) // +

console.log('end') // HIGHLIGHT

#### Collapsed code blocks

In some cases, such as large nested config files, you need readers to focus on a specific part of the code block while maintaining the context. You can do this by adding `focusOnLines=` to the code block. This collapses the code block and only shows the lines of code you specify.

<Tab.Group tabs={[ 'Preview', 'Markdown']}> Preview Markdown

    {
    "projects": {
    "my-app": {
    "architect": {
    "build": {
    "builder": "@angular-devkit/build-angular:application",
    "options": {
    "sourceMap": {
    "scripts": true, // +
    "styles": true, // +
    "hidden": true, // +
    "vendor": true // +
    }
    }
    }
    }
    }
    }
    }

{ "projects": { "my-app": { "architect": { "build": { "builder": "@angular-devkit/build-angular:application", "options": { "sourceMap": { "scripts": true, // + "styles": true, // + "hidden": true, // + "vendor": true // + } } } } } } }

#### Mermaid diagrams

Code blocks can also be used to show mermaid UML diagrams. When using these diagrams, make sure to include a text description of the diagram afterwards for accessibility and LLMs.

<Tab.Group tabs={[ 'Preview', 'Markdown']}> Preview Markdown

    sequenceDiagram
    Alice->John: Hello John, how are you?
    John-->Alice: Great!
    Alice->John: See you later!

sequenceDiagram Alice->John: Hello John, how are you? John-->Alice: Great! Alice->John: See you later!

### Product list

Use ``to render a list of products sourced from` useProduct`hooks. It links each product to` /{slug}` by default using the product's icon, color, and name.

Auto-source from a product data field (e.g. every product where `wizardSupport` is set):

<!-- prettier-ignore -->

    <ProductList
        sourceField="wizardSupport"
        sourceValues={[true, { value: "In development", color: "red" }, { value: "Coming soon", color: "yellow" }]}
    />

<ProductList className="grid gap-4 grid-cols-2 not-prose" sourceField="wizardSupport" sourceValues={[true, { value: "In development", color: "red" }, { value: "Coming soon", color: "yellow" }]} />

Products are grouped in `sourceValues` order. Plain values (`true`, `"some string"`) filter without an indicator. Object values (`{ value, color }`) also render a colored dot with tooltip text.

Manual list of products:

<!-- prettier-ignore -->

<ProductList className="grid gap-4 grid-cols-2 not-prose" products={["product_analytics", "web_analytics", "session_replay"]} />

Manual list with field-based filtering and indicators:

<!-- prettier-ignore -->

    <ProductList
        products={["product_analytics", "web_analytics", "feature_flags", "llm_analytics"]}
        sourceField="wizardSupport"
        sourceValues={[true, { value: "Coming soon", color: "yellow" }]}
    />

<ProductList className="grid gap-4 grid-cols-2 not-prose" products={["product_analytics", "web_analytics", "feature_flags", "llm_analytics"]} sourceField="wizardSupport" sourceValues={[true, { value: "Coming soon", color: "yellow" }]} />

Only the products whose `wizardSupport` value matches a `sourceValues` entry will render. Other props: `urlPrefix` (default `/`), `className`, `itemClassName`, `iconSize`.

### Wizard command

Use `` to render a copyable install button for the PostHog wizard CLI. Clicking the button copies the command to the clipboard and shows a toast notification.

The command automatically includes `--region eu` or `--region us` based on the user's feature flags.

Props:

| Prop | Type | Default | Description | | --- | --- | --- | --- | | `latest` | `boolean` | `true` | Appends `@latest` to the package name | | `slim` | `boolean` | `false` | Hides the "Learn more" link below the button | | `className` | `string` | `''` | Additional classes for the button element |

Slim mode (button only, no "Learn more" link):

<!-- prettier-ignore -->

Without `@latest` (used on the homepage and wizard page):

<!-- prettier-ignore -->

### Call to action

Adding `` to any article will add this simple CTA:

Don't overuse it, but it's useful for high intent pages, like comparisons.

### Feature comparison tables

When comparing features between two or more products, use the ``component which sources data from the` src/hooks/competitorData/` directory and lets you compare specific features across multiple competitors.

<!-- prettier-ignore -->

    <ProductComparisonTable
    competitors={['posthog', 'amplitude']}
    rows={['product_analytics']}
    />

Read more in the product & feature comparisons handbook page.

### Captions

You can add captions below images using the following code:

    Add you caption copy here

Here's an example of what it looks like:

Image: PostHog webshare pricing experiment

Adding the 'Buy Now' call to action and adjusting the text enabled Webshare to boost conversion by 26%

### Customer quotes

Add a styled quote component using the following code:

Product-specific quote

<!-- prettier-ignore -->

    <OSQuote
    customer="significa"
    author="tomas_gouveia"
    product="web_analytics"
    />

Generic quote

<!-- prettier-ignore -->

    <OSQuote
    customer="lovable"
    author="viktor_eriksson"
    quote={0}
    />

We mainly use them in customer stories and some product pages.

Quotes are sourced from the `useCustomers` hook and can reference product-specific quotes or general quotes by someone at a company. Be sure to add the customer's information to the `useCustomers` hook in `src/hooks/useCustomers.tsx`.

Example

<!-- prettier-ignore -->

    quotes: {
    viktor_eriksson: {
    name: 'Viktor Eriksson',
    role: 'Software Engineer',
    image: {
    thumb: 'https://res.cloudinary.com/dmukukwp6/image/upload/q_auto,f_auto/viktor_00c779a706.jpg',
    },
    quotes: [
    "PostHog is super cool because it is such a broad platform. If you're building a new product or at a startup, it's a no-brainer to use PostHog. It's the only all-in -one platform like it for developers.",
    ],
    },
    },

### Collapsible sections

The combination of `<details>` and `<summary>` components enables you to add a collapsible section to your page. Useful for FAQs or details not relevant to the main content.

    <details>
    <summary>Can I specify some events to be identified and others to be anonymous for the same users?</summary>

    Not if you already identified them. Once a user is identified, all _future_ events for that user are associated with
    their person profile and are captured as identified events.
    </details>

### Tabs

Tabs enable you to display different content in a single section. We often use them to show different code examples for different languages, like in installation pages.

To use them:

1. Import the `Tab` component.
2. Set up `Tab.Group`, `Tab.List`, and `Tab.Panel` for each tab you want to display. The `tabs` prop in `Tab.Group` should be an array of strings, one for each tab. This enables you to link to each tab by its name.
3. Add the content for each tab in the `Tab.Panel` components. You should use snippets for readability, maintainability, and to avoid duplication, but you can use multiple snippets in a single tab.

For example, here's how we set up the tabs for the error tracking installation page:

    Error tracking enables you to track, investigate, and resolve exceptions your customers face. Getting this working requires installing PostHog:

    <!-- prettier-ignore -->
    Web
    Next.js
    Python

You can default to a specific tab by passing the tab name in the query string like:

    /docs/product-analytics/installation?tab=web

### Links

#### Linking internally

Use Markdown's standard syntax for linking internally.

    [Link text](/absolute-path/to/url)

Be sure to use _relative links_ (exclude `https://posthog.com`) with _absolute paths_ (reference the root of the domain with a preceding `/`).

| | | | -------------------- | ------------------------------------------ | | Correct syntax | `/absolute-path/to/url` | | Incorrect syntax | `https://posthog.com/absolute-path/to/url` |

Open a new PostHog window

To open a link in a new window within the PostHog.com OS interface, use `state={{ newWindow: true }}` like:

<!-- prettier-ignore -->

    Link text

#### Linking externally

The ``component is used throughout the site, and is accessible within Markdown. (When used _internally_, it takes advantage of <Link to="https://www.gatsbyjs.com/docs/reference/built-in-components/gatsby-link/" external>Gatsby's` ` features like prefetching and client-side navigation between routes).

While that doesn't apply here, using it comes with some handy parameters that you can see in action via the link above:

- Add `external` to a) open the link in a new tab, and b) add the _external link_ icon (for UX best practices if forcing a link to open in a new window)
- If, for some reason, you need to hide the icon, use `externalNoIcon` instead

Example:

    click here

#### Private links

Sometimes we link to confidential information in our handbook. Since the handbook is public, it's useful to indicate when a link is private so visitors aren't confused as to why they can't access a URL (like a Slack link or private GitHub repo). Use the `` component for this. See an example (on our share options page.)

    click here

Private links will always open in a new browser tab.

### Mention a team member

Use this component to mention a team member in a post. It will link to their community profile and appears like this: Cory Watilo

There's also a `photo` parameter which will inline their photo next to their name like this: Cory Watilo

### Mention a small team

Use this component to mention a small team in a post. It will link to their team page and appears like this:

The default version shows the team's mini crest and name in a bordered "chip" style. There's also a `noMiniCrest` parameter to omit the mini crest and border for inline usage like this:

Both versions will show the full team crest on hover. Clicking the tooltip will open the team page in a new window.

### Embedded posts

You can embed what looks like ~~a Tweet~~ an X post using the `<Tweet>` component. It's used on the terms and privacy policy pages, but was componentized for use in blog posts to break up bullet points at the top of the post.

_Note: This does not actually embed an X post ; it's just styled to look like one._

Here's what a post looks like. It's designed to have a familiar look that makes it easy to scan.

If you show multiple posts in a row, they'll be connected by a vertical line to make it look like a thread.

Usage

Be sure to change the alert message which appears if you click one of the action buttons (reply, repost, like).

<!-- prettier-ignore -->

    <Tweet
    className="mx-auto"
    alertMessage="Gen Z? Don't get distracted. You're here to read our exciting embedded post component."
    >
    If you show multiple posts in a row, they'll be connected by a vertical line to make it look like a thread.

You can optionally center the post with the `mx-auto` class (shown in the example code, but _not_ used in the preview above).

Canonical URL: https://posthog.com/handbook/engineering/posthog-com/markdown

GitHub source: contents/handbook/engineering/posthog-com/markdown.mdx

Content hash: `0d073b8ca527413c`

Static reader notes

- `MDX_COMPONENT_STATIC_ADAPTER`: Adapted interactive MDX components for static reading: ArrayCTA, Caption, ImageSlider, JSWebErrorTracking, Link, MultiLanguage, NextJSErrorTracking, OSQuote, PrivateLink, ProductComparisonTable, ProductList, ProductScreenshot, ProductVideo, PythonErrorTracking, PythonInstall, SmallTeam, Tab, Tab.Group, Tab.List, Tab.Panel, Tab.Panels, TeamMember, Tweet, UploadSourceMaps, UploadSourceMapsSteps, WebInstall, WistiaEmbed, WizardCommand.