Data direction: This is a destination — Upstack sends event and conversion data out to this platform via server-side APIs.
How it works
When a visitor takes an action on your store, Upstack:- Captures the event through the Upstack Pixel and matches it to a known visitor profile using Upstack’s identity resolution.
- Enriches the event with identity data (distinct ID, email, IP, user agent, device info).
- Sends the event to PostHog using your Project API Key via the PostHog Capture API.
- PostHog records the event against the visitor’s distinct ID for analytics, funnels, and session replays.
Set up PostHog
Get your PostHog Project API Key
In PostHog, go to Project Settings → Project API Key. The key starts with
phc_ followed by alphanumeric characters.Note your data region
PostHog offers two data regions:
- US — Data hosted in the United States (
us.posthog.com) - EU — Data hosted in the European Union (
eu.posthog.com)
Add the destination in Upstack
In the Upstack dashboard, go to Destinations → Add Destination → PostHog. Enter:
- Project API Key — Your PostHog project API key (starts with
phc_) - Data Region — Select US or EU based on your PostHog project location
Optional: Configure additional settings
- Enable Auto Capture — Automatically capture pageviews and clicks
- Enable Session Recording — Enable session recording for user replays (requires PostHog session recording to be configured)
Credentials
| Field | Required | Description |
|---|---|---|
| Project API Key | Yes | Your PostHog project API key. Found in Project Settings → Project API Key. Starts with phc_. |
| Data Region | Yes | The region where your PostHog data is hosted: US or EU. |
| Enable Auto Capture | No | Automatically capture pageviews and clicks. |
| Enable Session Recording | No | Enable session recording for user replays. |
Event mapping
Upstack automatically maps e-commerce events to PostHog events with enriched properties.| Upstack event | PostHog event | Description |
|---|---|---|
PageView | $pageview | Page view on any storefront page |
ViewContent | view_item | Product detail page view |
ViewCategory | view_category | Category or collection page view |
ViewCart | $pageview | Cart page view |
AddToCart | add_to_cart | Product added to cart |
InitiateCheckout | initiate_checkout | Checkout started |
Purchase | purchase | Order completed |
Search | search | Search performed on storefront |
SignUp | sign_up | Account created |
Lead | lead | Lead form submitted |
Event properties
Each event sent to PostHog includes enriched properties from Upstack’s identity resolution:| Property | PostHog field | Description |
|---|---|---|
| Distinct ID | distinct_id | Upstack identity ID (resolved across sessions) |
| Current URL | $current_url | Page URL where the event occurred |
| Referrer | $referrer | Referring URL |
| IP Address | $ip | Visitor IP address |
| User Agent | $user_agent | Browser user agent string |
| Browser | $browser | Browser name |
| Device Type | $device_type | Device type (desktop, mobile, tablet) |
| Operating System | $os | Operating system name |
email | Customer email (when identified) |
E-commerce properties
For purchase and cart events, additional e-commerce properties are included:| Property | Description |
|---|---|
value | Total value of the event |
currency | Currency code (e.g., USD) |
order_id | Order ID (for purchases) |
search_query | Search query (for search events) |
items | Array of product items with product_id, product_name, product_brand, product_category, price, quantity, and variant |
FAQ
What is the difference between Upstack and PostHog's native Shopify integration?
What is the difference between Upstack and PostHog's native Shopify integration?
PostHog’s native integration only sees visitors that Shopify can identify. Upstack’s identity resolution matches anonymous sessions to known customer profiles using cookies, click IDs, and cross-session behavioral data. This means your PostHog funnels and cohorts include visitors that would otherwise be anonymous.
How does Upstack identify users in PostHog?
How does Upstack identify users in PostHog?
Upstack uses its identity resolution engine to assign a consistent
distinct_id to each visitor. This ID persists across sessions, devices, and browsers when Upstack can resolve the visitor’s identity. Anonymous visitors receive a temporary ID that Upstack attempts to merge when the visitor is later identified.Will I see duplicate events if I also have PostHog installed via another method?
Will I see duplicate events if I also have PostHog installed via another method?
Possibly. If you have PostHog’s JavaScript snippet or another integration sending the same events, you may see duplicates. Consider disabling overlapping event types in either Upstack or your other PostHog integration to avoid duplication.
How quickly do events appear in PostHog?
How quickly do events appear in PostHog?
Events typically appear in PostHog within 1-2 minutes of occurring on your storefront. Check Activity → Live Events in PostHog to verify events are arriving.
Can I use PostHog session recordings with Upstack?
Can I use PostHog session recordings with Upstack?
PostHog session recordings require PostHog’s JavaScript snippet to be installed on your storefront. Upstack sends server-side events to PostHog, which can be correlated with session recordings if you have both installed. Enable “Session Recording” in the Upstack destination settings to include session replay metadata.
Troubleshooting
Events not appearing in PostHog
Events not appearing in PostHog
If events are showing in the Upstack Live Event Stream but not arriving in PostHog:Steps to fix:
- Confirm the PostHog destination shows Active (green) in the Upstack dashboard
- Verify your Project API Key is correct and starts with
phc_ - Check that you selected the correct data region (US or EU) matching your PostHog project
- In PostHog, go to Activity → Live Events and look for events from Upstack
- If the destination status is red, disconnect and reconnect with a fresh API key
Events showing with wrong distinct_id
Events showing with wrong distinct_id
If events appear in PostHog but users aren’t being properly identified:Steps to fix:
- Verify Upstack’s identity resolution is working by checking the Live Event Stream for resolved identities
- Check that your PostHog project’s person identification settings match how Upstack sends distinct IDs
- Allow 24-48 hours for Upstack to build identity profiles for new visitors
For additional troubleshooting beyond PostHog-specific issues, see Troubleshooting: Events Not Reaching Destination.
Related
Identity Resolution
How Upstack ID connects anonymous sessions to known customers.
Destinations Overview
How Upstack Signal and Upstack Flows power different types of destinations.
Custom Events
Send custom events to PostHog and other destinations.
Events Not Reaching Destination
End-to-end diagnostic guide when events aren’t arriving at any destination.