Looks very cool and it definitely addresses a problem that not only many organizations have but also many individuals have. I know personally I have struggled with moving my data out of various services many times before.

The question I would have to you is this: if the API (or however a tap extracts information) for a given service changes, who is responsible for updating the tap, and is there any way to verify that a tap will extract the data correctly and that said tap isn't assuming an old version of the API?

(Sorry if I'm misunderstanding the way that Singer or any of its associated services work)