Instant App: Type an Idea, Press Enter, Get a Live App

[Juice10]

What: You type your idea, hit Enter, and—boom!—an instant web application is spun up with a backend, database, and all the glue in between.
Why: Drastically shorten the distance between an idea and a working product.
Questions:
How do we choose sensible defaults for frameworks, databases, hosting, etc.?
What are the security implications of spinning up ephemeral apps on the fly?
How can we store or export these “instant apps” so they can be further developed or shared?