# Google Cloud Client Libraries for Rust - Authentication
The Client Libraries for Rust are under active development. We are creating
placeholder crates so we can reference them in our code and tooling.
**WARNING:** this crate is under active development. We expect multiple breaking
changes in the upcoming releases. Testing is also incomplete, we do **not**
recommend that you use this crate in production. We welcome feedback about the
APIs, documentation, missing features, bugs, etc.
> This crate used to contain a different implementation, with a different
> surface. [@yoshidan](https://github.com/yoshidan) generously donated the crate
> name to Google. Their crate continues to live as [gcloud-auth].
[gcloud-auth]: https://crates.io/crates/gcloud-auth