Is Existential Existence Preceding Existence?

In the classical philosophical tradition, essence precedes existence. So you exist, but it's up to you to decide exactly what type of thing you are. We have no nature that determines things for us; we get to determine things on our nature. But in order to hold that as Simone de Beauvoir does is you have to declare war against those physical realities which anchor you and constantly remind you about who and what you are.