As a best-selling author, I invite you to explore my books on Amazon . Don't forget to follow me on Medium and show your support. Thank you! Your support means the world! I remember the first time I saw a project with more than one crate. I was working on a small command-line tool, and the codebase was growing. All the logic lived in a single src/main.rs . Functions were long, tests were a mess, and I kept accidentally breaking something while fixing something else. That’s when I learned about Cargo workspaces. A workspace lets you split a project into multiple crates that live in the same repository. They share the same Cargo.lock file and compile together. It’s like having several small workshops instead of one giant garage. Setting up a workspace is simple. You create a root Cargo.toml that lists the members. Each member has its own Cargo.toml and source tree. The workspace ensures that every crate uses the exact same version of every dependency.…