Thanks, this is the exact kind of intel I was looking for. Especially that they have a API connector and REST API - I was betting they DID have that, as it's a moderately easy thing for them to ad that makes custom extensions possible.

(With Zapier, I have used their so-called "Webhook" connector for that - set up an endpoint on my webapp that accepts a POST with a JSON payload, then make a zap that send data there in response to some trigger.)