[prasoonds]

So we discuss this briefly on our FAQ but let me try to expand on it.

Our goal is to make a modern literate programming tool. On a surface level, a tool like that would end up looking very similar to Jupyter, though with better features. We've mentioned some things we'd like to have in this final tool in our README and also in the post above.

Our first thought was to make a tool from scratch. The challenge was, it's very hard to get people to switch and so, we had to go where people already are - that meant Jupyter.

We could've made this one feature an extension with some difficulty (in-fact, our early experiments, we started by making an extension). It would have some downsides - we wouldn't have granular control over certain core Jupyter behaviours like we do right now (for eg, we wanted to allow creating hidden folders to store some files). But we probably could have made a 95% working version of Pretzel work as a jupyter extension.

The bigger reason we chose to fork was because down the line, we want to completely change the code execution model to being DAG based to allow for reproducible notebooks (similar to https://plutojl.org/ for eg). Similarly, we want to completely remove Codemirror and replace it with Monaco (the core editor engine in VSCode) to provide a more IDE like experience in Jupyter. These things simply couldn't have been done as extensions.