Clean Core & ABAP Cloud
SAP’s strategic shift to upgrade-safe extensibility. Keep your S/4HANA standard clean, extend everything using released APIs — with RAP, BAdI, CAP, and ABAP Environment on BTP.
CLEAN CORE · ABAP CLOUD · RAP · CAP · BAdI · ATC
THE PHILOSOPHY
What Is Clean Core?
SAP’s Clean Core strategy — formalized since 2022 — defines a single principle: keep your S/4HANA standard clean, and build everything else on BTP or ABAP Cloud. No more custom modifications to SAP standard objects (Z-changes to ABAP programs, direct table writes, unreleased BAPIs). Every extension must use only released APIs, released CDS views, and published BAdI definitions — significantly reducing upgrade adaptation effort and avoiding direct dependency on SAP internal objects.
This is not a restriction — it is an architectural upgrade. Clean Core extensions can be tested independently, deployed continuously, and significantly reduce upgrade effort across S/4HANA releases — with regression testing remaining necessary especially in private cloud and on-premise landscapes. The ABAP Test Cockpit (ATC) enforces these rules at development time, flagging violations before they reach production.
EXTENSIBILITY MODEL
Three Tiers of ABAP Cloud Extension
ABAP Cloud organizes all extensibility into three tiers — defined by where the code runs and how it connects to S/4HANA. The target architecture for every tier is to use released APIs and governed extension points. Exceptions should be documented and managed through ATC governance.
TIER 1 — IN-APP
Key User & BAdI Extensions
Runs inside the S/4HANA ABAP stack. Uses predefined extension points — BAdI definitions and Key User tools — to inject custom logic without modifying standard code.
- ✅ BAdI Implementations (Enhancement Spots)
- ✅ Custom Business Objects (CBO)
- ✅ Key User Extensibility UI5 Flex
- ✅ Custom Fields & Logic (SPRO)
- ✅ In-App OData services (RAP in S/4HANA)
TIER 2 — ABAP CLOUD
RAP — ABAP RESTful Model
Build complete transactional business objects (BOs) using CDS View Entities + Behavior Definitions. Exposes OData v4 services for Fiori Elements apps. Runs on S/4HANA or ABAP Environment on BTP.
- ✅ CDS View Entity (data model)
- ✅ Behavior Definition (CRUD, draft, actions)
- ✅ OData v4 + Fiori Elements auto-UI
- ✅ ABAP Environment on BTP
- ✅ Business Event publishing (Event Mesh)
TIER 3 — SIDE-BY-SIDE
CAP & BTP Extensions
Full cloud-native applications on BTP — Node.js or Java, deployed to Cloud Foundry or Kyma. Connects to S/4HANA only through released OData APIs or Event Mesh. Ideal for multi-system, multi-tenant scenarios.
- ✅ CAP (Node.js / Java) on Cloud Foundry
- ✅ Kyma (Kubernetes) on BTP
- ✅ SAP Build Code (AI-assisted IDE)
- ✅ SAP Build Apps (no-code/low-code UI)
- ✅ Integration via Event Mesh / OData
KEY TOOLS
The ABAP Cloud Developer Toolchain
🛡 ABAP Test Cockpit (ATC)
ATC is the enforcement engine for Clean Core. It runs automated checks against your custom ABAP code, flagging any use of unreleased APIs, direct table access, or deprecated language elements. We configure ATC with SAP-delivered Clean Core check variants and integrate it into your transport workflow — so violations are caught at development time, not after upgrades.
📐 ABAP Development Tools (ADT)
Eclipse-based IDE for ABAP Cloud development. ADT enforces the ABAP for Cloud Development language version — the restricted language subset that enables only clean-core-compliant syntax. It provides real-time ATC integration, CDS editor, Behavior Definition editor, and RAP generator tooling. We set up ADT with your BTP ABAP Environment or S/4HANA system and configure team-wide settings.
📦 SAP Build Code
SAP Build Code is SAP’s AI-assisted development environment — a Joule-powered IDE for ABAP, CAP, and UI5 development on BTP. Joule for Developers can assist with code generation, code explanation, unit test creation, and development tasks across ABAP and CAP scenarios. We onboard development teams to Build Code, establish project templates, and integrate with CI/CD pipelines for automated testing and deployment.
🔍 Custom Code Migration Tool
SAP’s Custom Code Migration (CCM) tool analyzes your existing Z-code inventory — scanning for non-released API usage, direct table access, and obsolete ABAP language features. It produces a prioritized migration backlog: which custom programs need remediation before Clean Core compliance, and which can be replaced by standard SAP functionality or released BAdIs.
🛡 The Golden Rule of ABAP Cloud
All custom ABAP code must use ABAP Language Version: “ABAP for Cloud Development” — the restricted syntax version that enforces released APIs only at compile time. This single setting prevents the entire class of upgrade-breaking modifications. ATC clean core check variants validate compliance before every transport to production.
Set the ABAP Language Version to "ABAP for Cloud Development" in ADT or the package settings. · No direct SELECTs from SAP tables · No unreleased BAPI/Function Module calls · No modifications to SAP standard includes
OUR SERVICES
Clean Core & ABAP Cloud Consulting
🔍 Clean Core Assessment
We run the SAP Custom Code Migration tool against your system and produce a prioritized list of all custom code that violates Clean Core rules. Effort estimates, risk ranking, and a phased remediation roadmap — delivered as a structured backlog you can bring directly into your sprint planning.
🔧 BAdI Migration
Replace classic user exits, BADIs (old-style from R/3), and modification objects with modern Enhancement Framework BAdI implementations using released BAdI definitions. We map each existing modification to the correct released extension point and implement the clean-core-compliant replacement.
⚙️ RAP Development
Design and build RAP business objects for custom transactional scenarios — new CDS View Entities, Behavior Definitions with managed/unmanaged implementation, custom actions and determinations, draft handling, and OData v4 service exposure. We cover both S/4HANA RAP and ABAP Environment on BTP.
☁️ CAP Side-by-Side Extensions
Build cloud-native side-by-side extensions on BTP using the Cloud Application Programming Model (CAP) in Node.js or Java. We design the CDS data model, implement service handlers, configure HANA Cloud persistence, set up XSUAA security, and deploy to Cloud Foundry or Kyma — with full CI/CD pipeline.
🛡 ATC Setup & Governance
Configure ABAP Test Cockpit with SAP’s Clean Core check variants, integrate ATC into your transport workflow (gated transports), set up quality gates in ABAP Environment on BTP, and train your development team on reading and remediating ATC findings. We establish a sustainable Clean Core governance process.
🎓 ABAP Cloud Training
Hands-on workshops for ABAP development teams transitioning from classic ABAP to ABAP Cloud. Topics: RAP from scratch, BAdI with Enhancement Framework, CDS annotations, ABAP for Cloud Development language restrictions, ATC remediation patterns, and CAP basics for ABAP developers. Tailored to your team’s current S/4HANA version and skill level.
RELATED TOPICS
Ready to Move to Clean Core?
Tell us your current S/4HANA version, upgrade timeline, and volume of custom Z-code. We will reply within one business day with a Clean Core assessment plan — starting with an automated ATC scan of your landscape.