QuakeML is both an executable binary that can be run, and a library that can be used in Rust programs.
Installing quakeml usgs executables
Assuming you have Rust/Cargo installed, run this command in a terminal:
cargo install quakeml
It will make quakeml usgs commands available in your PATH if you've allowed the PATH to be modified when installing Rust. cargo uninstall quakeml uninstalls.
Adding quakeml library as a dependency
Run this command in a terminal, in your project's directory:
cargo add quakeml
To add it manually, edit your project's Cargo.toml file and add to the [dependencies] section:
quakeml = "0.1.8"
The quakeml library will be automatically available globally.
Read the quakeml library documentation.