PostHog

Ace reads PostHog to measure product impact during an incident, finding which events changed, how many users are affected and which feature flags are involved. Insight alerts can open incidents, and Ace can roll a flag out or switch it off as a kill switch.

What Ace readsCopy Anchor Link

Ace reads one PostHog project while it investigates a workload that lists PostHog under Investigation sources or routes its alerts.

• Events whose volume changed most in the incident window, compared with an equal window before it.
• 15-minute counts and distinct users for one event.
• Flags that match a search, with their active state and rollout percentage.
• Exceptions in the window, grouped by error tracking issue, with type, message, event count and affected users.
• Your team's annotations around the incident.
• The incident's failure event after a fix, to confirm the problem stopped.

Ace also adds the connected project to the System Map.

What Ace can changeCopy Anchor Link

Ace proposes PostHog actions only after an admin turns on Allow Ace to run approved actions for the connection. Each one needs approval by default, and earned autonomy can let either one run under an Automatic policy for a workload and environment you confirm. See Actions and approvals.

Ace applies these safeguards:

• Ace writes with the flag version it saw at approval, so PostHog refuses the change if anyone edited the flag since.
• PostHog also refuses a switch when the flag needs a PostHog approval or other active flags depend on it.
• Ace rechecks the incident between stages.

These actions need the feature_flag:write scope, and Settings shows whether the key has it.

What opens an incidentCopy Anchor Link

PostHog alerts open incidents only on workloads that route this connection (Integration alerts on, PostHog selected). Ace accepts insight alerts sent to a webhook destination and drops alerts that no workload routes.

• An $insight_alert_firing event opens or joins an incident at high severity. Each alert is its own group, so repeated firings of one alert join one incident.
• An alert that reports "not firing", "resolved" or "ok" resolves it.
• Ace ignores other events, and it accepts a custom body only if the body names an alert ID.

Ace doesn't poll PostHog, so without the webhook PostHog alerts don't reach Ace.

Before you startCopy Anchor Link

• The admin role in Ace.
• A PostHog insight with an alert, or permission to create one.
• Your Project ID, under Settings > General in Project token & ID.

Credentials and permissionsCopy Anchor Link

Limit the key to this one project. Don't use the Read-only access preset, which grants far more than Ace needs.

Set upCopy Anchor Link

1. Create a personal API key in PostHogCopy Anchor Link

1. Open Settings > Personal API keys and choose Create personal API key.
2. Label it Ace and set Expiration, for example 90 days.
3. Under Organization & project access, choose Projects and select only this project.
4. Leave Select preset alone. Under Scopes, set Read on Project, Query, Feature flag and Annotation. Set Write on Feature flag only if Ace should roll out or switch flags.
5. Create the key and copy it.

2. Connect PostHog in AceCopy Anchor Link

1. Open Settings > Data sources and choose PostHog.

2. Fill in the form:

   Field	What to enter
   Personal API key	The key you created.
   PostHog URL	Optional. Leave blank for https://us.posthog.com. Use https://eu.posthog.com for the EU cloud, or your own host.
   Project ID	The numeric project ID.

3. Select Connect PostHog. Before it saves, Ace checks that the key can read the project, run a query and read feature flags.

A self-hosted PostHog URL must use HTTPS and be reachable from the public internet, because Ace doesn't connect to private or internal network addresses.

3. Send alerts to AceCopy Anchor Link

1. In the Alerts section, copy the webhook URL.
2. Select Generate token and copy the token, which Ace shows only once.
3. In PostHog, open the insight to watch, open Alerts, create an alert and add a Webhook destination.
4. Paste the URL and keep the default JSON body. Under Secret headers, add Authorization with the value Bearer, a space and the token.

4. Route alerts to a workloadCopy Anchor Link

Open the workload in Ace, turn on Integration alerts, and select PostHog as a source.

5. Optional: allow actionsCopy Anchor Link

Turn on Allow Ace to run approved actions. To let flag actions earn Automatic, confirm their workload and environment on the same panel.

Confirm it's workingCopy Anchor Link

• If the host is wrong for your region, the connection's checks suggest the US or EU host.
• The Alerts badge shows Not set up, Waiting for first event, Verified or Last delivery failed. Trigger the alert or send a test from PostHog, and the badge turns Verified when the first delivery with the right token arrives.
• A failed delivery shows the reason, such as a bearer token that doesn't match.
• To rotate the token, select Generate a new token and update the PostHog secret header.

DisconnectCopy Anchor Link

1. In Ace, open the PostHog connection under Settings > Data sources and select Disconnect. To stop actions and keep the connection, turn off Allow Ace to run approved actions instead.
2. In PostHog, remove the webhook destination from your alerts and delete the Ace personal API key. Ace creates nothing in PostHog.

Next stepsCopy Anchor Link

• LaunchDarkly
• Actions and approvals
• All integrations