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She wrote all this code by hand to take humanity to the Moon
(thelemmy.club)
Margaret Hamilton, NASA's lead developer for Apollo program, stands next to all the code she wrote by hand that took humanity to the moon in 1969
Also, this is an obscure assembly variant specifically for the computers in the Apollo mission. Not sure about the specifications on that, maybe there is a handbook, but I doubt it.
Rewriting the code to x86 or anything seems improbable since you'd pretty much have to guess what the instructions are actually doing.