What happens when a type adds driving such as:

newtype SupplyT s m a = SupplyT (StateT [s] m a)
deriving (Functor, Monad, MonadTrans, MonadIO)
Two questions:

How does the deriving implement the instance?

Is there a way for me to add  my own classes in the deriving?  for example

newtype .....
   deriving( xyz)


Thanks

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