I'm interested in programmatic track generation.

After some examination of the code, it seems like it would be easier to manipulate the official editor than make a standalone program. For example, the minified class Tx is basically the editor class and is constructed once at the beginning of a session.

If you want to programmatically generate tracks, just add the code below to the Tx constructor in main.bundle.js:

window.editor = this;

Then you can use the methods of the editor object.