@alex I love PlatformIO as a great build platform for #IoT. For future instruction videos, I suggest encouraging secure programming and using MQTTS, i.e. always use TLS.
I've seen too many IoT #security issues that we need to work as an industry on shift left and encourage secure programming right from the start.
@sgryphon excellent point. I spent a lot of time over the past couple of years modifying Tasmota to do MQTT over TLS the way I wanted it to. I am also focussed on how we secure MQTT-SN presumably with DTLS but it's all something of a black art. I did talk chaps at the MQTT steeting committee about my belief there is a need to address security rather than taking the view it's out of scope for the spec.