[yarwelp_]

That is the official way that you install the Rust toolchain. https://www.rust-lang.org/en-US/install.html

Rust is still undergoing changes frequently enough that most package manager repos have a very old version of the Rust toolchain in terms of what it is capable of doing.

For example the version of rustc that you get from Ubuntu default repositories was too old to compile my pgen when I checked some weeks ago.

And exactly because the tool is for generating passwords I don't want to distribute pre-compiled binaries of my tool myself, and therefore until I get pgen itself into package manager repos I tell people to download the Rust toolchain and to build my tool from source themselves as I did above.