# Google Cloud Client Libraries for Rust - Certificate Authority API
The Certificate Authority Service API is a highly-available, scalable
service that enables you to simplify and automate the management of
private certificate authorities (CAs) while staying in control of your
private keys.
The client library types and functions are stable and not expected to change.
Please note that Google Cloud services do change from time to time. The client
libraries are designed to preserve backwards compatibility when the service
changes in compatible ways. For example, adding RPCs, or fields to messages
should not introduce breaking changes to the client libraries.
## Quickstart
The main types to work with this crate are the clients:
- [CertificateAuthorityService]
## Features
- `default-rustls-provider`: enabled by default. Use the default rustls crypto
provider ([aws-lc-rs]) for TLS and authentication. Applications with specific
requirements for cryptography (such as exclusively using the [ring] crate)
should disable this default and call
`rustls::crypto::CryptoProvider::install_default()`.
## More Information
- Read the [crate's documentation](https://docs.rs/google-cloud-security-privateca-v1/1.5.0)
[aws-lc-rs]: https://crates.io/crates/aws-lc-rs
[ring]: https://crates.io/crates/ring
[CertificateAuthorityService]: https://docs.rs/google-cloud-security-privateca-v1/1.5.0/google_cloud_security_privateca_v1/client/struct.CertificateAuthorityService.html