How to use a local unpublished crate in Rust?

Hi everyone! I've just started learning Rust and I'm trying to structure my project. I have a main application, and I want to extract some common logic (e.g., API work or utilities) into a separate crate so I can use it in multiple projects. The problem is that this crate is not yet ready for publication on crates.io — it's an internal library that I want to test locally.\n\nI created a `my_lib` folder next to the main project. Inside it, there's `Cargo.toml` and `src/lib.rs`. In the main project's `Cargo.toml`, I tried specifying the dependency in different ways, but Cargo complains. Here's an example structure:\n\n```\n/workspace\n├── main_project\n│ ├── Cargo.toml\n│ └── src\n│ └── main.rs\n└── my_lib\n ├── Cargo.toml\n └── src\n └── lib.rs\n```\n\nIn `main_project/Cargo.t