Starboard.gg is similar but also allows JavaScript, CSS, or HTML cells to execute in the same notebook. Python has access to the DOM and can share variables with JavaScript.
I love the idea of Starboard. But seems like the development has stalled?
Yes. Last commit was 5 months ago [1]. Seems like a great idea though.
What I don't like it is that they invented yet another markdown syntax for code cells - it is the opening bracket # %[python] with no closing bracket.
There already is a popular markdown code cell syntax of [2]
```python
```