Do I have any control should be my data stored or evaluated?
seems like properties solve that undercover
If you need data to be evaluated through all chain at each request, it sounds like pull based FRP, but Kefir is push based.
Can it be both explicitly? I mean you always have two ways to deal with data, evaluate or store. Always store is a bad idea, always evaluate even worse. You can have some default behavior, but it can be cool option to make it possible to make some (okey) props "evaluable". Of course if it is not contadics your desigh philosophy of the library.
You talking about property's current values right? Just to clarify :) Now it works automatically. Properties might evaluate data on "first request", but then will cache the result in
I think it theoretically possible to make this configurable, but not easy for sure.
It means you mostly keep it in memory
I'm personally did have any problems with the fact that current value caches.
But you are right it spends some memory.
It became an issue if you operate with some big data occasionally
Yes, might be an issue and Kefir doesn't help to solve this unfortunately.