I have chosen Javascript because of it's simplicity and readability. Node.js is also a fantastic enviroment for development and production.
Goal: To fully mimic the websocket client provided by hivemind.
Building the application started out with reading about MQTT, studying it's purpose and functioning. Having understood the concept, finding the right frameworks/libraries to function was at hand. A simple search led to MQTT.js(https://github.com/mqttjs/MQTT.js), which is a fantastic client library. Choosing layout tools was simple, picking out vue and vuetify(personal favorites).
What I learned: All about MQTT, and it's role in IoT.
Actual experience with the used languages is mainly small personal projects being worked on the side.