The live code editor developed for the Khan Academy Computer Science curriculum.
Demos of how to use the editor can be found in the demos/ directory. Specifically a good place to start is with the simple demo:
To configure the LiveEditor...
For a deep dive into the components of the LiveEditor, read this wiki.
You can use the pre-built copies of everything inside the build/ directory. If you wish to make some changes and re-build the library from scratch you'll need to install some dependencies:
git submodule update
npm install
bower install
# Build the Ace editor files
cd bower_components/ace
npm install
make build
At this point you can make a fresh build, using Gulp:
gulp