Hey, thanks for writing this! Got a simple cron job working nicely and I'm impressed with the API's elegance.

One thing I like about temporal is the ecosystem includes a UI, but it's not very useful here because everything is nippy encoded, which is convenient but not interoperable. Do you have any thoughts on this? e.g. pluggable encoding or remote codec endpoint facilities

Hi, and thanks so much for sharing this SDK!

I'm evaluating Temporal to help with orchestration within a polyglot Clojure + Python system, so I'm particularly considering interop between different languages, and I recognise this might not be on your list of priorities at all.

From what I can tell, cross-language workflow interop is currently tricky with this SDK for a couple of reasons:

1. Only activities defined in clojure with defactivity can be invoked, so an activity that may be implemented by a worker in another language is inaccessible from this SDK. (As a workaround one can declare a stub activity in Clojure that never gets executed, but this feels a bit hokey.)
2. All activity params/results are encoded with nippy rather than JSON, so by default workflow data will be unreadable by SDKs in other languages. I guess this choice was made so that Clojure-to-Clojure activity interop works smoothly, with seamless serialisation of :keywords etc. For interop beyond Clojure, would you expect that a Data Converter could be written to convert nippy data to/from JSON or similar?

I'd rather not drop down to the Java SDK if I can avoid it, so I thought I'd check in here to see if you have any tips — thanks!