I don't know how, but they found me

You thought you had left them behind. You thought that crash landing in an abandoned spaceport junkyard on an obscure planet would be enough.
It wasn’t. 
The first nuke impacted not far from your camp. You haven’t finished making repairs to your ship yet. Now, the pressure is on to get the repairs done and get off this rock before they get lucky and hit you

Race through the junkyard, collecting parts for your spaceship while hoping a nuke doesn't fall on you.

Get through the launch sequence before the spreading radiation overwhelms you. 

Escape.