You're right, it's assuming Rust is installed since it's talking about updating the compiler. But let's install Rust instead then:

`curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`

Now you can `rustup install <version>` easily with everything taken care of. Of course, the latest stable release is automatically installed already. And Rust provides automatic install scripts for Windows, Mac, and Linux. Whereas Go is more involved than is expected for any modern language.