Example code not complete

[basickarl]

servers.listen(function(){
^

ReferenceError: servers is not defined
    at Object.<anonymous> (/home/karl/dev/javascript/sandbox.js:16:1)

Example code is not complete!

[esbenvb]

The start of the code should be something like

const mqttServer = require('mqtt-server');
 
const servers = mqttServer({
// .....

That will at least run - but I cant, make it forward any messages though...