Ok so I have a work in progress which means DCE will work for js-joda - see Cljc.java-time will drop all npm/foreign-lib dependencies. It’s taken ages, but all the bits are there - I just need to finish it off… which I’ll try to do in the next couple of weeks or so.
So to be clear, although DCE works on it, (so if you don’t use any of the lib, nothing gets included in your js bundle) - because of the nature of the library, if an end user does use some of jsjoda, they end up pulling in most of the lib. It’s just the nature of js-joda that it’s a bit like a ball of string - ie start pulling on one bit and the rest follows. So not the best outcome I could have hoped for.
Longer term, the new platform dates for JS should be a good solution - in that cljc.java-time could use that and be dependency free - see https://github.com/henryw374/cljc.java-time/wiki for some thoughts on that, including the fact that the api is not completely 1:1 with java.time.