HotSpot is built on top of the Strongtalk VM, which is very interesting in several ways. First, it's a Smalltalk implementation with optional strong static typi

HotSpot is built on top of the Strongtalk VM, which is very interesting in several ways. First, it's a Smalltalk implementation with optional strong static typing. Second, since 2006 it's been available as open source: http://strongtalk.org/ http://strongtalk.org/ I believe, along with Common Lisp and its VM, it's the only such option on the market. Clojure may have optional static typing -- which, running on the HotSpot JVM, would mean bringing this "full cycle" -- but I need to RTFM before I say for sure.