Hi, I've put down some words about how we would go about adding support for side inputs to the streaming API. People are increasingly asking for such a feature, which would allow joining a main stream with some slowly changing inputs that can be used for enriching data, among other things.
The design document is available here: https://docs.google.com/document/d/1hIgxi2Zchww_5fWUHLoYiXwSBXjv-M5eOv-MKQYN3m4/edit?usp=sharing Any feedback is very welcome! Cheers, Aljoscha
