Thanks for the response. Unfortunately that kind of announcement doesn’t really help us determine if the image change will break our build. It is helpful after the fact to give us guidance in what may have gone wrong.
The reason it doesn’t really help us determine if our builds will break is because usually the problem is with some subtle interaction. For example, in this case there is a bug with how ChromeDriver 2.23 interacts with Chrome 53. When you post an announcement that you’re going to update the Circle environment, we simply don’t have the engineering resources to go through that list, find all the things that are updated, update our local environment to match, and see if everything works. All we can reasonably do is say, “Well, if builds start breaking in 3 days, it’s probably because Circle pushed out their update.”
A better stopgap solution might be to enable us to start a build on a circle release candidate image. That way we can click a button, see if the build passes, and if it doesn’t we can know something critical broke and can prepare to deal with it. But even this is a poor solution because it requires our direct interaction and vigilance, and if something is broken we still have to go fix it before the change goes live.
I realize this is a hard thing to get right, and I appreciate you and your team’s work. I’m glad to hear this is something that’s actively being thought about and worked on.