I was just following the example from the docs, my use case is more like this:
.
├── lib.rs
└── foo/
└── mod.rs
└── one.rs
└── two.rs
└── three.rs
└── four.rs
└── bar/
└── mod.rs
└── one.rs
└── two.rs
└── three.rs
└── four.rs
Which feels to me like a very common folder structure in other languages.