ipython uses (last I checked) node.js or pandoc(haskell) to convert markdown to html in nbconvert. You shouldn't need node or haskell if you're not using nbconvert

the server is written in tornado

It doesn't do any such thing for me. I `pip install`ed it just now and it ran fine. You mean the shell, right?

When I do this on Fedora 22:

repoquery --requires python-ipython-notebook

I get node.js stuff.

The notebook is a web interface, node-based tools (bower, less) are used to package the in-browser part: http://jupyter-notebook.readthedocs.org/en/latest/developmen... It's unclear why fedora adds it as a dependency, it shouldn't be necessary for a packaged notebook application as far as I can see, only to package or run from source.

Why not?

Well it also installs Python Tornado which does event based web serving...and I would think iPython Notebook would be written in...Python. Maybe its just me.

This is probably why it was renamed to Jupyter Notebook.[0]

0. https://blog.jupyter.org/2015/04/15/the-big-split/