[taneq]

I'd think a happy medium would be using an open source CI system and testing new versions on a test server before deploying them to prod.

Then again, I come from a largely non-web background where external dependencies aren't just accepted as inescapable. I guess if your entire business is producing an add-on for some other company's web service (not saying yours is but many out there seem to be) then what's one more on the pile?

[Heliosmaster]

that's exactly what their CI is. An open source CI system that you can deploy on your own server (and plug to either gitlab.com or your self-hosted instance of Gitlab).