It writes the code for you.
If you like codeCanvas, please donate to help insure the future development of the open source offering.
It costs money to keep codeCanvas open source and free. The advertisements help keep the lights on :-)
Here is the complete client side code for the codeCanvas editor. It is a streamlined version of the same code used in the codeCanvas Desktop project on Github.
Download the codeCanvas core - The complete editor and sample bootstrap tools
Here are a couple examples of what the open sourced code can do at the moment. All the canvas functionility is there but the integration with App.js needs work.