Major Description
I suggest that a single canonical C library be written to implement most of the multi-lang support.
A library of this sort would allow people using Python, Ruby, OCaml, Haskell, Node, Lua, etc etc to simply bind to the C library and expose all Samza functionality without having to implement it directly.
As an example, there are a handful of Kafka clients for Python and they are spotty in terms of their support for the full feature set.