ABAP RESTful Application Programming Model (RAP) PART 3: A Senior Architect's Guide to Building Modern Fiori Apps

If you’ve been building SAP applications for more than a few years, you’ve seen the landscape shift dramatically. We went from classic Dynpro screens to Web Dynpro, then to SAPUI5 with OData services wired up manually, and now we’re in the era of the ABAP RESTful Application Programming Model (RAP). And I’ll be honest with you — RAP is the most significant architectural leap I’ve seen in the ABAP world in over a decade. But here’s the thing: most teams I’ve consulted with are still building new Fiori apps the old way. They’re creating function modules, manually exposing OData services, and wondering why maintenance is killing them six months later. If you’re one of those teams, this guide is for you. We’re going to break down ABAP RAP from a senior architect’s perspective — what it actually is, how the layered architecture works, and how to build a real, working application without wasting weeks on boilerplate. What Is ABAP RAP and Why Should You Care? The ABAP RESTful Application Prog