Beaker allows you to run multiple languages in the same notebook and communicate between them (you can set a variable in one language and read it in another and

Beaker allows you to run multiple languages in the same notebook and communicate between them (you can set a variable in one language and read it in another and it just works, magically). It is JavaScript-centric and can be scripted and extended in JS. Has some nice modern UI features like interactive dataframe display, one click sharing, expandable sections. In particular, the R support is quite good compared to IPython3. Yes, it is compatible with the IPython backend, so if you already have that installed, you can access it. Also you can import ipynb files. Compatibility is pretty good but not everything works, eg widgets do not.