The standard #Rust types for IPv4 and IPv6 addresses are in std, not core, so embedded developers can't use them (the smoltcp folks had to roll their own almost identical ones) -- and nor can people writing crates aimed at both embedded and hosted use. But there's a PR to fix this by moving them into core (unstable at first), hopefully to appear in a new Rust release soon: https://github.com/rust-lang/rust/pull/104265 #embedded #network #smoltcp