JFC. When will open source projects like @rustlang learn that putting toxic people like this in positions of ANY authority is unacceptable. https://github.com/marshallpierce/rust-base64/issues/213 . He’s showing you who he is, and you’re not listening.
simple-base64. It works the way you’d expect:
use simple_base64 as base64; ... let decoded = base64::decode("YmFzZTY0")?;