404 by http://vert-x3.github.io/vertx-lang-scala/

Hi. 
I am new to vert.x and want to learn it.
The URL http://vert-x3.github.io/vertx-lang-scala/ is leading in 404 😢 

Also i want to start to learn to build microservices with vert.x in scala an using REST and GRPC. But it is very difficult to find examples for that.