Don't worry! We are all busy and sometimes is normal to read too quickly a message on internet. My advice would be to have one single broker no matter what, so

Don't worry! We are all busy and sometimes is normal to read too quickly a message on internet. My advice would be to have one single broker no matter what, so don't replace the websockets server with another instace of mosquitto, but just use the same old instance. Then, the ice thing of working with a protocol is that you don't care of the implementation, hence just keep using mosquitto until it support the load and the, eventually swap verneMQ if necessary. Be careful with your custom authentication logic, that if you want to migrate will require you to port it over. Verne provide plugins for Auth so it is not an huge deal but you need to think a little bit ahead. But again, if mosquitto is working fine just keep it! Cheers!