Static types in a distributed system with hot swapping, live upgrades of parts of a running system, isn't trivial. Types are great at stating and preserving gl

Static types in a distributed system with hot swapping, live upgrades of parts of a running system, isn't trivial. Types are great at stating and preserving global invariants. Invariants sometimes do vary as systems evolve, though. You may need to handle polymorphism in your data flow mid-transition. And runtime polymorphism is just another phrase for dynamic typing.