Talk from Hermann:
In a List[Option[A]] or Future[Option[A]] we want to access the value of type A conveniently without nested mapping and flatMapping.
We can avoid nested mapping with composed functors.
Functors compose, but monads do not! What can we do?
Monad transformers to the rescue!
After going through functor composition I show how 2 monads are bolted together with a monad transformer and how to use this construct. I demonstrate this with the Option transformer OptionT and will end up with best practices.