SPFX (SharePoint Framework) is a new client-side SharePoint development tool, easy integration with SharePoint data, and support for open source tooling based on node and heavily relies on web pack and gulp to provide for it’s tooling.
This quick starts works
on windows, mac and Ubuntu
However, I am running into issues running it on Cloud 9 please see https://github.com/SharePoint/sp-dev-docs/issues/533
The framework allows you to preview your WebPart in a browser before deploying to SharePoint. So you can develop without SharePoint until you are ready.
I would appreciate any help in getting this resolved.