Workspaces
Multi-crate projects.
What Is a Workspace?
A workspace is a set of related crates that share a single Cargo.lock and a common target directory. It's the standard way to manage multi-crate projects.
The Root Manifest
The workspace root has a Cargo.toml with a [workspace] table listing the member crates. The root itself usually has no package.
[workspace]
members = ["app", "core", "utils"]
resolver = "2"