Analytics Integrations

Koryla can forward experiment assignment events to your analytics platform automatically. When a new visitor is assigned to a variant, the Worker fires a background event (using waitUntil — so it never blocks the page load).

Supported platforms

Setting up an integration

1. Go to Integrations in your workspace dashboard
2. Select your analytics platform
3. Enter your credentials (Measurement ID, API key, etc.)
4. Toggle it on

Changes take effect within 60 seconds (the KV cache TTL).

Event schema

All integrations receive the same event data:

Google Analytics 4

Setup

You need a GA4 Measurement ID (G-XXXXXXXXXX) and a Measurement Protocol API secret.

To get the API secret:

1. Open GA4 → Admin → Data Streams → your stream
2. Scroll to Measurement Protocol API secrets
3. Create a new secret and copy the value

Enter both in the Integrations settings.

What gets sent

Koryla sends a experiment_viewed custom event via the GA4 Measurement Protocol:

{
  "name": "experiment_viewed",
  "params": {
    "experiment_id": "...",
    "experiment_name": "Homepage CTA Test",
    "variant_id": "...",
    "variant_name": "Blue button"
  }
}

Analyzing in GA4

In Explore → Free form:

• Dimension: experiment_name, variant_name
• Metric: conversions, sessions, or your goal metric
• Filter: event name = experiment_viewed

PostHog

Setup

Enter your PostHog Project API key (starts with phc_). If you're using PostHog Cloud EU, also update the host to https://eu.i.posthog.com.

What gets sent

{
  "event": "$experiment_started",
  "distinct_id": "[session_id]",
  "properties": {
    "experiment_name": "Homepage CTA Test",
    "variant": "Blue button",
    "$experiment_id": "...",
    "$variant_id": "..."
  }
}

Analyzing in PostHog

Use PostHog's Experiments feature or build a funnel in Insights:

1. Filter by $experiment_started where experiment_name = "Your Test"
2. Break down by variant
3. Add a goal event as the next step in the funnel

Plausible

Setup

Enter your Plausible domain (e.g. yoursite.com). Plausible Analytics must be set up on that domain.

What gets sent

Koryla sends a custom event named Experiment with props:

event: Experiment
props: {
  experiment: "Homepage CTA Test",
  variant: "Blue button"
}

Analyzing in Plausible

Go to your Plausible dashboard → Goal conversions → filter by Experiment.

Mixpanel

Setup

Enter your Mixpanel Project token (found in Project Settings → Access Keys).

What gets sent

{
  "event": "Experiment Viewed",
  "properties": {
    "distinct_id": "[session_id]",
    "token": "...",
    "experiment_id": "...",
    "experiment_name": "Homepage CTA Test",
    "variant_id": "...",
    "variant_name": "Blue button"
  }
}

Amplitude

Setup

Enter your Amplitude API key (found in Project Settings).

Custom Webhook (Growth)

For any platform not listed above, you can configure a custom webhook URL. Koryla will POST a JSON payload to your URL on every new variant assignment.

Payload

{
  "event": "experiment_viewed",
  "experimentId": "...",
  "experimentName": "Homepage CTA Test",
  "variantId": "...",
  "variantName": "Blue button",
  "sessionId": "...",
  "timestamp": "2026-04-10T22:00:00Z"
}

Authentication

Set a secret token in the integration settings. Koryla includes it as a header:

X-Koryla-Secret: your-secret-token

Verify this header on your server to ensure the request is coming from Koryla.

Events fire only once per visitor

Analytics events are fired only on new variant assignments — not on every page view. A returning visitor who already has the sp_ cookie will not trigger another event. This keeps your data clean and prevents inflating event counts.