ssz-derive is a procedural macro. It will run at compile time and transform your program's source code.
Adding ssz-derive macro(s) as a dependency
Run this command in a terminal, in your project's directory:
cargo add ssz-derive
To add it manually, edit your project's Cargo.toml file and add to the [dependencies] section:
ssz-derive = "0.2.0"
You may need to import the macro(s) with use ssz_derive::*.
ssz_derive documentation.