I'm a little unclear as to when and under what conditions this results in non-heap objects, now (<= 64-bits?) and in the future (???). I thought that was the _ENTIRE_ point of this project, so I was surprised to see they can be null (did that change from before?). If it is always and forever limited to 64-bits, I fail to see the point of this entire project, as it would have been far simpler to add syntactic sugar (simply pass primitives underneath the covers) as Scala did to create value types vs. JVM changes.