Yes, I eyeball the migration code. You could call it code review, whatever. There is no way I am running migration code automatically. In fact I am not sure what you mean by "automatically"? As in a non-human triggers the migration? But do you review the code?

First of all, migrations do not happen in my case that often that I need them to run unattended/automatically.

Second, I don't trust any migration system to spit out flawless code. Maybe I have trust issues.