This is just a quick demo of the code-your-model language implemented with JetBrains MPS, version 2019.2.3. This project uses MPS-extensions.
In this first iteration, I just followed the syntax of the original, internal groovy DSL. Naturally, one could now add alternative notations, including graphical ones and even one that looks more like a document than code. Further below an alternative editor with mainly different styling is shown.
Anyway, here are some GIFs to get a feeling for what the standard editors looks like and how it "feels":
Actual ReadMe: TODO!