Installing Binaries from Crates.io with cargo install

The cargo install command allows you to install and use binary crates locally. This isn’t intended to replace system packages; it’s meant to be a convenient way for Rust developers to install tools that others have shared on crates.io. Only packages that have binary targets can be installed. A binary target is the runnable program that gets created if the crate has a src/main.rs or another file specified as a binary, as opposed to a library target that isn’t runnable on its own but is suitable for including within other programs. Usually, crates have information in the README file about whether a crate is a library, has a binary target, or both.

All binaries from cargo install are put into the installation root’s bin folder. If you installed Rust using rustup.rs and don’t have any custom configurations, this will be $HOME/.cargo/bin. Add that directory to your $PATH to be able to run programs you’ve gotten through cargo install.

For example, we mentioned in Chapter 12 that there’s a Rust implementation of the grep tool for searching files called ripgrep. If we want to install ripgrep, we can run:

$ cargo install ripgrep
Updating registry `https://github.com/rust-lang/crates.io-index`
 Downloading ripgrep v0.3.2
 ...snip...
   Compiling ripgrep v0.3.2
    Finished release [optimized + debuginfo] target(s) in 97.91 secs
  Installing ~/.cargo/bin/rg

The last line of the output shows the location and the name of the installed binary, which in the case of ripgrep is rg. As long as the installation directory is in your $PATH as mentioned above, you can then run rg --help and start using a faster, rustier tool for searching files!