Generic Webhook?

Good afternoon - I'm building an API integration from a third party app to Constant Contact. The upload portion of the integration is working fine, but now I'm stuck on how to sync back from Constant Contact to the third part app.

Can a generic webhook be setup to send data to a third party app? The webhook would ideally fire when a patron unsubscribes / subscribes, and ideally another webhook trigger if there are profile updates made on the patron account.

Thank you.