Using RS256 JWT with ESP8266 and Arduino IDE

Hello,

I'm trying to connect my ESP8266 modules to a MQTT server and I want to practice using JWT. Does anybody have any experience doing this or can point me to some helpful links? I see some examples with SHA256 but I want to implement a private/public key pair with RS256.

I am speculating using Google Cloud Core IoT JWT, ArduinoJSON, and the PubSubClient libraries.

Thank you! Looking forward to some helpful guidance!