The CSR builder is called [`x509_cert::builder::RequestBuilder`](https://docs.rs/x509-cert/0.3.0-pre.0/x509_cert/request/index.html). It's located outside of [`x509_cert::request`](https://docs.rs/x509-cert/0.3.0-pre.0/x509_cert/request/index.html) and doesn't have CSR anywhere in its name, nor is it mentioned in the `request` module. cc @baloo