This whole write up is what gives me nightmares, kudos for anyone who works in this field.

You cannot write a test suite to catch regressions. How would you build a ci that detects sd boot failures on commit?

A static analyser couldn't help. Rewriting in rust isn't an advantage. You probably wont get help on stack overflow. Given all the above you might try to approach it as formally as possible, from the top down. That works in some spaces. Except half the writers problem was specs not being clearly laid out.