[AlotOfReading]

I do safety critical code. I would consider banning allocation (e.g. just using Core) or avoiding certain data structures a completely feasible strategy to avoid unsafe if I wanted to exclude it from my safety model. It's what I'm already doing in C++. The difference is that in C++, I can never prove the absence of undefined behavior from any part of the codebase, even if I review every single line. Even if I could, that proof might be invalidated by a single change anywhere.

It's not easy in Rust, but it's possible.