[btown]

VS Code extensions are pretty limited - you can override the renderer for an editor tab, but if you want multiple things within a custom interface to be treated as first-class editor tabs by the larger environment (and by the larger extension ecosystem), that's not really possible. Forks are a reasonable step as long as they don't fall behind!

[slightwinder]

Do you really need a first-class-editor for working directly from the canvas? Wouldn't it be enough to use the canvas just for navigation and show a rendered picture of the code, but open a separate editor (maybe side by side?) for the real work?

[btown]

My understanding is that Haystack's mission is to explore this design space more fully than others have before, so I think they're making the right decision to be audacious here!