Built with reasonably recent McCLIM and SBCL. At one point, had it running under CCL on one of my Raspberry Pi boxes (the 3, I think). Would have made a cool pocket, ersatz LispM.

Source code:

https://bitbucket.org/symbolicsimulation/com.symsim.oss.lisp...

Yeah, I know it's a mess. With the exception of updating the calls to the inspector just now (in case anybody tried to build it), it's just as I last left it a few years ago - with the proverbial hood open, subsystems not really working, and parts lying all over the floor.