There''s also the checked crate which introduces a Checked type similar to core::num::Wrapping: checked::Checked - Rust
It provides a pretty good example of what a self-contained addition of checked arithmetic wrappers might look like if added to the standard library.
There was a pre-RFC about it posted here cc @pdolezal: Where is std::num::Saturating? (Going to pre-RFC!) - #27 by pdolezal