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The Sign-Off Table

Lesson 1 of 5

Where ABAP runs

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ABAP is no longer a language that lives in one kind of system. The same language, with different rules switched on, now runs in an on-premise SAP S/4HANA system, in SAP S/4HANA Cloud Private Edition, in SAP S/4HANA Cloud Public Edition and in the SAP BTP ABAP environment, a platform service where you build ABAP apps outside the ERP. Before you write a line of code, or plan a test, you need to know which of these you are working in, because it decides which language rules, tools and APIs you get.

SAP BTP ABAP environmentA cloud ABAP platform on SAP BTP for side-by-side apps and services. ABAP Cloud only.
SAP S/4HANA Cloud Public EditionSAP-run multitenant ERP. On-stack developer extensibility uses ABAP Cloud only.
SAP S/4HANA Cloud Private EditionYour own ERP instance, run under RISE. ABAP Cloud and classic ABAP are both available.
SAP S/4HANA (on-premise)Customer-run ERP. Same choice as Private Edition: ABAP Cloud or classic ABAP.
Four places ABAP runs today, from the most restricted to the most open.
The Sign-Off Table · thesignofftable.com/academy/sap-abp-101

On-stack and side-by-side

SAP describes two broad ways to extend an ERP. On-stack extensions run inside the SAP S/4HANA system itself: a custom field, a BAdI implementation, a new RAP business object that reads ERP data through released CDS views. Side-by-side extensions run on a separate platform, typically SAP BTP, and talk to the ERP through remote APIs and events. The SAP BTP ABAP environment is the side-by-side option for teams who want to stay in ABAP. Community blogs by SAP have long nicknamed it "Steampunk", and the on-stack ABAP Cloud environment inside SAP S/4HANA "embedded Steampunk"; you will still hear both names in projects.

On-stack extensions live inside SAP S/4HANA and read through released APIs; side-by-side extensions run on SAP BTP and reach the ERP only through remote APIs and events.
The Sign-Off Table · thesignofftable.com/academy/sap-abp-101

One development model spans all of these. SAP's documentation states that the ABAP Cloud development model is delivered with the SAP BTP ABAP environment, SAP S/4HANA Cloud Public Edition, and SAP S/4HANA Cloud Private Edition and on-premise SAP S/4HANA as of release 2022 (ABAP 7.57). In the two public cloud offerings ABAP Cloud is the only model. In Private Edition and on-premise you can use ABAP Cloud and classic ABAP side by side in the same system.

The system decides which development models are on offer; in Private Edition the choice between ABAP Cloud and classic ABAP is made object by object.
The Sign-Off Table · thesignofftable.com/academy/sap-abp-101
WhereDevelopment modelsTypical use at Contoso
SAP BTP ABAP environmentABAP CloudA future fleet portal backend that should not live inside the ERP
SAP S/4HANA Cloud Public EditionABAP CloudNot used; Contoso chose Private Edition
SAP S/4HANA Cloud Private Edition 2025ABAP Cloud and classic ABAPCMD / CMQ / CMP: converted custom code plus new ABAP Cloud extensions
SAP ECC 6.0 EHP 8Classic ABAP onlyED1 / EQ1 / EP1 until the Q3 cutover

Where Contoso Motor Co. runs ABAP before and after its conversion.

What this means for Contoso

Contoso Motor Co. is converting SAP ECC 6.0 EHP 8 to SAP S/4HANA Private Edition under RISE. The conversion carries thousands of custom objects into the new system: reports, enhancements, and the custom tables behind the core return program, where fleet customers pay a deposit on each alternator and get it back when they return the old unit. All of that arrives as classic ABAP. At the same time, Kenji, the ABAP development lead, has been told that new extensions should follow ABAP Cloud wherever a released API exists. So CMD, the new development system, will hold both kinds of code. Knowing which is which is the first job of anyone who develops or tests there.

  1. TodayECC 6.0 EHP 8All custom code is classic ABAP in ED1, EQ1 and EP1
  2. Mock conversionsCode arrives in CMDCustom code is converted and adapted, still classic ABAP
  3. Q3 go-liveS/4HANA Private EditionConverted code runs in CMP; new work starts in ABAP Cloud
  4. After go-liveGradual modernizationHigh-value objects are refactored toward ABAP Cloud release by release
How Contoso’s ABAP estate changes across the program.
The Sign-Off Table · thesignofftable.com/academy/sap-abp-101

What would you do?

Grace asks Kenji whether a new deposit-tracking extension should be built inside CMD or as a separate app. The extension reads core return agreements and customer data, and Maria's team will use it daily in the ERP. What is the best first answer?

Key points
  • ABAP runs on-premise, in Private Edition, in Public Edition and in the SAP BTP ABAP environment.
  • ABAP Cloud is the only model in Public Edition and the BTP ABAP environment.
  • Private Edition and on-premise (2022 and later) offer ABAP Cloud and classic ABAP side by side.
  • On-stack extensions run inside SAP S/4HANA; side-by-side extensions run on a separate platform.
  • A converted system holds mostly classic ABAP, so know which model each object uses.

Check your understanding · not graded

Lesson check

  1. 1. In which offering is ABAP Cloud the only available ABAP development model?

  2. 2. From which SAP S/4HANA release does SAP list ABAP Cloud as available in Private Edition and on-premise?

  3. 3. What best describes a side-by-side extension?

  4. 4. After Contoso’s conversion, what kind of ABAP will most custom objects in CMD be on day one?