From “Steampunk” to ABAP Cloud: How SAP Unified Its ABAP Extensibility Strategy

For SAP customers modernizing their ERP landscapes, few terms have generated as much confusion as “Steampunk.” Once a shorthand for SAP’s most forward-leaning ABAP innovation, the concept has now largely disappeared from SAP’s messaging. Yet the architectural principles Steampunk introduced have not faded. Instead, they have become the foundation of SAP’s modern ABAP strategy under a single, unifying model: ABAP Cloud.

Understanding why the Steampunk era emerged, and why it ultimately dissolved into ABAP Cloud, offers important insight into SAP’s Clean Core mandate and what it means for extensibility decisions across SAP S/4HANA, SAP Business Technology Platform (BTP), and hybrid landscapes.

The Steampunk Experiment: Side-by-Side ABAP Goes Mainstream

When SAP launched the SAP BTP ABAP Environment in 2018, internally codenamed “Steampunk,” it marked a significant break from decades of in-core ABAP customization. Instead of embedding custom code directly inside the SAP ERP system, Steampunk ran ABAP as a Platform-as-a-Service (PaaS) on SAP BTP, decoupled from the S/4HANA core.

The goal was explicit: preserve upgrade stability by forcing custom code to interact with S/4HANA only through released, versioned APIs. Direct database access, file system operations, classic Dynpro screens, and unrestricted OpenSQL updates were deliberately blocked. In their place, SAP introduced a restricted ABAP language subset aligned with cloud-native principles.

Central to this model was the RESTful Application Programming Model (RAP). RAP replaced procedural ABAP patterns with declarative behavior definitions, built-in transactional handling, draft support, and concurrency control. Capabilities that had previously been hand-coded or implemented via BOPF were now standardized and enforced by the framework.

For early adopters, the results were tangible. Steampunk-based extensions proved resilient across S/4HANA upgrades and support packs, eliminating a major historical source of downtime and remediation cost. However, this stability came at a price: development teams now had to maintain two distinct ABAP paradigms, classic ABAP on-stack and strict ABAP off-stack, creating organizational and skills fragmentation.

Why Steampunk Ended and ABAP Cloud Took Over

The Steampunk era did not end because it failed. It ended because it succeeded too well.

By 2021, SAP recognized that the principles enforced in Steampunk—API-first design, restricted language usage, and upgrade-safe extensibility—were not niche requirements for side-by-side development. They were prerequisites for SAP’s entire product roadmap. At SAP TechEd 2021, SAP introduced “Embedded Steampunk,” later formalized as the SAP S/4HANA Cloud ABAP Environment, bringing the same restricted ABAP model directly into the S/4HANA stack.

By late 2022, SAP consolidated its messaging under the ABAP Cloud banner. The critical shift was conceptual: ABAP Cloud is not a separate runtime or deployment option. It is a development model that applies consistently across SAP BTP, SAP S/4HANA Cloud Public Edition, Private Edition, and even SAP S/4HANA on-premise 2022 and beyond.

This unification eliminated the need for “Steampunk” as a distinct term. Whether code runs side-by-side on BTP or embedded within SAP S/4HANA, SAP now expects the same discipline: released APIs, RAP-based services, and compliance with ABAP Cloud Syntax checks.

Strategically, this aligns directly with SAP’s Clean Core initiative. New platform innovations, from Joule-powered developer assistance to event-driven extensions via SAP Event Mesh and analytics integration with SAP Datasphere, assume ABAP Cloud compliance. Custom code that bypasses these rules increasingly sits outside SAP’s forward roadmap.

For SAP customers, this convergence also reduces historical friction between deployment models. An ABAP Cloud-compliant RAP service developed on BTP can be redeployed to SAP S/4HANA Cloud Private Edition with limited refactoring, provided API contracts are respected. This portability is particularly relevant for hybrid landscapes, selective carve-outs, and post-merger system integration scenarios.

At the same time, SAP is modernizing the ABAP toolchain to support this shift. Git-based workflows via abapGit, CI/CD integration using gCTS, and expanding editor support (e.g., Visual Studio Code) signal SAP’s intent to meet developers where they already work, rather than forcing adoption through proprietary tooling alone.

What This Means for SAPinsiders

Clean Core becomes enforceable, not optional. Technology leaders must now assume ABAP Cloud compliance as a baseline, not a future aspiration. Customers who refactored custom code into RAP-based services report materially lower upgrade remediation effort, often reducing regression cycles from weeks to days during SAP S/4HANA upgrades. Over time, this translates into more predictable release planning, lower operational risk, and reduced dependence on last-minute remediation projects.

ABAP skills finally converge across landscapes. The collapse of the classic-versus-Steampunk divide simplifies workforce planning and architectural governance. Teams using ABAP Cloud report higher code reuse across BTP and SAP S/4HANA projects, especially in hybrid scenarios where side-by-side and embedded extensions coexist. This convergence also shortens onboarding time for new developers and reduces long-term skills fragmentation across SAP programs.

Evaluation shifts from features to discipline. When assessing partners or internal teams, executives should prioritize API governance, RAP maturity, and ABAP Test Cockpit (ATC)  Cloud compliance over raw delivery speed. Organizations that invested early in automated syntax checks and released-API usage have consistently avoided rework as SAP tightens Clean Core enforcement across releases. As SAP’s roadmap increasingly assumes ABAP Cloud adherence, this discipline becomes a leading indicator of long-term extensibility success rather than a technical nice-to-have.