In this 17-minute developer focused demo, we may appreciate the increased number of SPFx integrations in Teams Toolkit on Visual Studio Code.
Vesa Juvonen focuses here on the ease of building a tab project and then adding an additional tab to the project. See how Teams Toolkit encapsulates the SPFx solution to its own sub-folder.
All development, testing and debugging is done live in TypeScript and use F5 for hot reloads. Azure integrations, code samples, etc. are just around the corner.