You have to version your apis or make everything backwards compatible. For data migrations if there's some big breaking change the you typically need some out o

You have to version your apis or make everything backwards compatible. For data migrations if there's some big breaking change the you typically need some out of band sync process. There's no magic bullet once something is out in the wild. When you introduce a breaking change you have to either a, accept it will break people and that's their problem, b, figure out a way not to make it breaking, c, support old and new for a while, or d, drop the feature. It's just a cost that you have to factor in while planning, and frequently one of the more significant ones. We've chosen d many times.