Cartographer from the end of the world

Hi! I don't expect this to get any traction at all cause it's just a thing I'm doing for fun but this is a story thing in the form of an epistolary (story told through letters)
(Please note that Étole uses Xe/Xem and Atlas uses They/Them)
This also isn't a fan fiction of any sort, it's all my original characters and story
And it's set in a crumbling dystopian world! Where everyone lives in 'forts' on concrete pillars above the ground, or huge robotic cranes (birds)