Puts your migration projects to shame.
Although I suppose it could actually be easier depending on how the code works- perhaps it's just simple bare metal assembly without the approx 10^99999 libraries a modern python stack has.
What's hard about their work is 1) it's really, really slow to communicate with, so you can't iterate quickly, 2) the tech is really old and unlike today's stuff, so it's very specialized domain knowledge.