At the moment, our member site has its own email preferences area. These preferences are fed into Marketing Cloud data extensions and are used when segmenting for email sends. We use the global Marketing Cloud unsubscribe to manage unsubscribes. The issue we have is that we're not syncing the unsubscribe status back to the member preferences.
I can see it would be possible to run extracts and imports etc, but this isn't really acceptable when real-time integration is required.
Can SSJS be used to call an external API when someone unsubscribes, or will a data extension log be needed that is referenced by the SSJS in an automation?