> In server context I agree, in command line API where you need to wait for the answer either way, it doesn't matter because that you block or wait, you pause the execution for your single user.

CLI tools doesn't mean you can do multiple IO things at once. But that's besides the point. You're doing something with an unexpected side-effects. It doesn't matter the context.

> I don't mind discussing this for 1.0, but we shouldn't add breaking changes before that point.

Uhm, now **is** the time to do breaking changes. Before 1.0 get's too close.