ArchLinux's PKGBULD generator from Cargo.toml manifest file
At first install rust and cargo:
$ pacman -S rust cargo
Then install this package:
$ cargo install cargo-pkgbuild
Now you can create PKGBUILD from your project Cargo.toml:
$ cd my-rust-project
$ cargo pkgbuild
Edit the resulting PKGBUILD to your taste and enjoy!