The default algorithm the [jsonwebtoken crate](https://crates.io/crates/jsonwebtoken) is using is ``ECDSA`` with ``SHA-256``.
```bash
openssl ecparam -name prime256v1 -genkey -out private-key.pem
openssl pkcs8 -topk8 -nocrypt -in private-key.pem -out private-key-pkcs8.pem
openssl ec -in private-key.pem -pubout -out public-key.pem
```