Yes, presuming that the author of the unsafe code in question has manually verified the effective safety in all relevant scenarios. `unsafe` is an assertion to

Yes, presuming that the author of the unsafe code in question has manually verified the effective safety in all relevant scenarios. `unsafe` is an assertion to the Rust compiler that you know what you're doing, and you will preserve its guarantees as far as external observers are concerned. I might point out to the grandparent post that even the basic vector collection in Rust is full of unsafe {} blocks.