I did not try it. In truth I do not have a card with esp 32. Before buying it, however, I would have liked to have the opportunity to exploit it with a dedicated library that exploited all its features, how to set the qos at each level.
I saw the library here https://github.com/espressif/esp-mqtt/blob/master/README.md
Thank you.
@Erel is 100% correct, the rMQTT does in fact work with an ESP32. I have it currently running on an ESP-WROOM-32 (DOIT - ESP32 DEV V1) with absolutely no issues whatsoever.