For using the Web client API, no compilation is needed so you can use your favorite code editor(Notepad, Notepad++ and so) or any other IDE you want.
Creating a new widget consist of 4 phases:
- Creating the widget JS.
- Creating the widget library JS.
- Creating the manifest.
- Adding the manifest Meta tag into the site.
In addition you will need your developer ID that can be taken from your developer page.