Clean Core in Legacy Systems: The Inventory with the ABAP Test Cockpit
The most common reaction to Clean Core in established SAP systems: “We have twenty years of custom development in the system – where should we even start?” The answer is unspectacular but effective: with a clean inventory. Before anything is migrated, replaced, or rebuilt, you need transparency about what actually exists in the system, how […]
From Tier 1–3 to Level A–D: Understanding the New Clean Core Level Model
Anyone who has been involved with Clean Core in recent years is familiar with the three-tier extensibility model. However, since the update of the ABAP Extensibility Guide in Summer 2025, a new landscape applies: the Clean Core Level Concept with four levels A to D. The good news first – if you are already developing […]
Clean Core in SAP S/4HANA: What it means—and why it is worth starting now
“Clean Core” is one of the most discussed topics around SAP S/4HANA—and at the same time one of the most frequently misunderstood. Many companies ask themselves: Do we now have to throw away everything we have built up over the years? The short answer: No. But it is worth taking a closer look. What does […]