Xargo is “a drop-in replacement for cargo”, so every cargo command also works with xargo. You can do e.g. xargo --help, xargo clean, or xargo doc. However, the build command gains additional functionality: xargo build will automatically cross compile the core library when compiling for custom targets.

https://os.phil-opp.com/set-up-rust/#target-specifications

https://os.phil-opp.com/set-up-rust/#compiling

switch to nigthly:
https://github.com/rust-lang-nursery/rustup.rs#working-with-nightly-rust

rustup install nightly
rustup default nightly
rustup update