Ask HN: How to build a Google Cloud Shell like feature?

Recently, I started playing with GCE and have been pretty impressed by the Cloud Shell implementation. They even make VI bindings work.

We could use something like this at work too so I was wondering, what would be a good resource to start if I have to go on implementing something like this? Our front end app is in Angular and APIs are served by Python/Java services but we are language/library agnostic.

Topics that I can study?