Thanks for the reply. I think if you combine unsafe with raw pointers instead of borrows you relax the rules enough to avoid this. But in this specific corner of things, I haven’t had direct experience so you may very well be right.

There are still some Rust-specific details you would still need to handle—as you mentioned, uninitialized memory—but for that one specifically I haven’t found MaybeUninit to be particularly cumbersome.