In the last few years we used Vert.x to prototype and develop several IoT related projects. Most of the projects use MQTT for lightweight messaging between the connected devices (or things ;)) and the applications. The messaging is handled by an external broker liker Mosquitto. Instead of using an external broker it’s now possible to connect MQTT enabled devices directly to Vert.x using the Vert.x MQTT server project. Although the project is still in Tech Preview we’ll show you how use it to create a MQTT server within Vert.x. At first we add the snapshot repository to our build.gradle file.