Very nice explanation. Gives a good insight how you can "think in observables". Two small things 1. instead of merging zero$ into connectionClosed$ you can use

Very nice explanation. Gives a good insight how you can "think in observables". Two small things 1. instead of merging zero$ into connectionClosed$ you can use the startWith() method. 2. Instead of using the head method to pluck the first item of an array you could use array destructuring. (But I can understand that you wouldn't do it in this to limit the amount of "new" concepts)