Every new Fabric feature gets the same first demo: a prettier report. Rayfin and Fabric Apps (preview) can do far more. Define a data model in TypeScript and you get a database, GraphQL API, Entra SSO, row-level security and hosting, deployed to a workspace with one command.

So what do you build when your data platform can ship software? Rob shows apps people actually use: writeback tools that fix data rather than admire it, an admin console calling the Fabric REST APIs through server-side functions, and a cycling and fitness app that pulls rides from Strava, lands them in OneLake and turns training data into something you act on, not just look at.

Along the way: schema changes that don't eat production, dev-to-prod promotion, keeping secrets out of the frontend, and an honest view of where the preview still creaks.

You'll leave with patterns, a repo, and a better answer than "another report".