1) modern interface 2) polyglot architecture (multiple languages work together in the same notebook) 3) native electron version

yes i am one of its developers.

here's an example of working with Python and D3/JavaScript together: https://pub.beakernotebook.com/#/publications/560c9f9b-14e6-...

and the electron version: https://github.com/twosigma/beaker-notebook/wiki/Electron-Be...