To get notified when a flow execution fails outside of testing, set a URL for AP_NOTIFICATION_URL. To make a personalized notification channel, you use activepieces to create a flow with a webhook trigger and choose your notification preference (e.g. Slack, Email). Copy the webhook URL and set it for AP_NOTIFICATION_URL. Here’s an example payload send by activepieces: 
{
  "body": {
    "type": "run.failed",
    "payload": {
      "run": {
        "id": "0km7v4Ke44TgEtA3HUnts",
        "flowId": "oyvBZc2seQ4LTPXLamgOo",
        "status": "FAILED",
        "created": "2023-03-31T22:07:42.513Z",
        "updated": "2023-03-31T22:07:43.536Z",
        "projectId": "g1EcUOGl2LaNQQA3AsQmN",
        "startTime": "2023-03-31T22:07:42.511Z",
        "finishTime": "2023-03-31T22:07:43.535Z",
        "environment": "PRODUCTION"
        "flowVersionId": "6nxv1FXCQaaa2pxzLDfIx",
        "flowDisplayName": "Flow 1"
      },
      "owner": {
        "id": "LFknXPv6FMhiUQFfVMZl0",
        "email": "mo@example.com",
        "lastName": "Doe",
        "firstName": "John"
      }
    }
  },
  "method": "POST",
  "headers": {},
  "queryParams": {}
}