It's something I've been working on for a while, but because the architecture is under constant flex, it's actually more valuable to be able to know how to "experience" or discover the architecture in the compiler code itself than to have a separate document to follow, since it's very easy for that document to get out of date quickly. I am building up a set of documents that discuss some of the core idioms and ideas though, and I hope to have something come of this live session that I can maybe put into an interactive document that people can work with.