This is a very beautiful and interesting project, and contains some themes that I've been thinking about myself recently (representations of code vs. data, interactive development environments, text markup, wikis).

I'm curious as to your take on the following opinion:

Even if your representation for an imperative programming language and declarative markup language are the same (I quite like using a parenthesized prefix notation for both), it's beneficial to cleanly separate those two languages in order to preserve a clean and distinct set of semantics for both.

(you can also extend this to a "presentation language" - what I'm getting at is that you can take the view that the tripartite separation of HTML, CSS, and JS in web technologies is actually a feature because it leads to a cleaner design than trying to mix all of those languages together (although I think that all of those particular languages have their own sets of flaws))

λ way is a very interesting project and I'm curious to see where it will go!