Just a quick comment till I can get home. There are three main layers of in use. The more Lisp like layer in apps/ and cmd/. The lowest level VP assembler and an assembler with stack variables and expression compiler I call C-Script. This is my hobby and a follow up to Taos that I did back in the 90’s. See ‘Virtual Processor’ page on Wikipedia for link articles of various scans from back then. Got to head into the car now.....