Docusaurus

To easily track your Docusaurus site, you can install the PostHog plugin. This enables you to autocapture pageviews, clicks, session replays, as well as use the other features of PostHog such as surveys.

Install

Once you have your Docusaurus site set up, install the PostHog plugin:

npm install --save posthog-docusaurus

or

yarn add posthog-docusaurus

If your site sets a Content-Security-Policy, it needs to allow PostHog. This applies to the snippet and to package installs alike: the SDK lazy-loads extra bundles (session replay, surveys) from PostHog's CDN, and sends events to the ingestion host. PostHog serves from subdomains of posthog.com that change over time, so allow the wildcard:

PostHog AI

script-src 'self' https://*.posthog.com;
connect-src 'self' https://*.posthog.com;
worker-src 'self' blob: data:;

script-src covers the snippet and the lazy-loaded bundles, connect-src covers event ingestion and feature flags, and worker-src covers session replay. The toolbar needs a few more, or use a reverse proxy so everything is first-party. Failing to do so causes silent failures where capture and identify calls never send, so the integration looks complete while zero events arrive. Remember connect-src falls back to default-src, so default-src 'self' blocks event delivery even when the script itself is bundled.

Next, add it to your Docusaurus config with your project token and instance address, both of which you can find in your project settings.

// docusaurus.config.js
module.exports = {
  plugins: [
    [
      "posthog-docusaurus",
      {
        apiKey: "<ph_project_token>",
        appUrl: "https://us.i.posthog.com", // optional, defaults to "https://us.i.posthog.com"
        enableInDevelopment: false, // optional
      },
    ],
  ],
};

Run your site again to see events autocaptured by PostHog.

Note:You can pass additional PostHog config options to the plugin, but they are passed through JSON.stringify(), so functions (such as before_send) are not supported.

Identifying users

Identifying users is required. Call posthog.identify('your-user-id') after login to link events to a known user. This is what connects frontend event captures, session replays, LLM traces, and error tracking to the same person — and lets backend events link back too.

Use a stable ID from your auth system when possible, not an email or display name. Send those as person properties instead. If your app has no other stable key, email works as a fallback if they are unique. Never a shared literal like "anonymous" or "user", which pools many people onto one person and corrupts their data. When no ID is available at all, skip the identify and retain the anonymous distinct ID that's automatically assigned.

Call posthog.reset() on logout, so the next person to use the browser doesn't inherit the last one's identity.

See our guide on identifying users for how to set this up.