"Isn't Mendix unsuitable for core systems like SAP because it's low-code?" "Can it really handle enterprise-level system development?"— IT departments considering implementing Mendix often encounter these kinds of questions.
In short, Mendix supports "side-by-side extensions," which allow you to extend user-facing applications on top of core systems such as SAP without compromising their functionality. This article will explain the mechanism for integrating SAP and Mendix from a technical perspective, based on typical architectural patterns seen in Mendix implementation examples overseas.
Why is the idea of "extending SAP" necessary?
Many manufacturing companies that have implemented SAP use the Production Management Module (PP) to manage production orders, BOMs (Bills of Materials), and production results. However, because SAP 's standard screens are designed to cover the entire business process, they have many operation items and are not optimized for the workflow of factory floor staff.
However, customizing SAP itself to improve usability at the operational level would require significant verification effort with each change, hindering future version upgrades (such as migration to S/4HANA). Because SAP is a system that prioritizes robustness and standardization, it faces the dilemma of being structurally difficult to respond quickly to detailed requests from the operational level.
In overseas examples of Mendix use, the approach taken to address this dilemma is to "add a user-facing application layer on the outside of SAP 's core, without altering it." At the heart of this approach is side-by-side extension using Mendix.
In fact, this idea aligns with SAP 's own direction. In recent years, SAP has discouraged traditional development methods that directly customize the internals (such as modifications using ABAP) and has strongly promoted a "clean core" approach that extends applications from external sources via APIs. Mendix is a platform that excels at application extensions in line with this clean core concept and is also certified as an official SAP partner.
Basic Architecture for SAP Extensions with Mendix
A typical configuration seen in overseas manufacturing examples involves integrating SAP and Mendix, dividing them into the following three roles:
1. SAP: System of Record
SAP will continue to handle core business data, including inventory management, accounting, and quality inspection result recording. SAP's standard functions and data models will remain unchanged and will be maintained as the primary data source.
2. Mendix: A layer of business logic and UI
We extract the ever-changing business logic and user interface, such as on-site workflow management, screen display, and input validation, to the Mendix side. Instead of directly operating SAP, on-site personnel will use applications built on Mendix to carry out their work.
3. API Integration: A loosely coupled point of contact connecting the two.
Mendix and SAP are connected via a loosely coupled system based on the OData API. This system exchanges only the necessary data without modifying SAP's internal structure, making it less susceptible to the effects of SAP upgrades and patch applications.
This idea of "extending externally without changing the core" is the essence of how Mendix functions as an "add-on" for SAP.
This three-tiered architecture is not just theoretical. Macnica itself has built and operates an internal application using this exact configuration, which integrates internal SAP order data with Mendix and automatically generates delivery date response data for customers.
Examples of data integration
To understand what kind of data is actually exchanged, here's a summary of the key integration points highlighted by overseas Mendix implementation support companies:
| Linkage points | Data flow |
|---|---|
| Obtaining manufacturing orders | Mendix automatically retrieves manufacturing orders issued by SAP (PP module) via API. Field personnel can then view the order details without logging into SAP. |
| BOM (Bill of Materials) integration | BOM information linked to manufacturing orders is retrieved from SAP, and work procedures and checklists are automatically generated on the Mendix side. |
| Registration of quality inspection data | Inspection results recorded on-site are entered into Mendix and automatically reflected in SAP's Quality Management (QM) module. |
| Reflection of production results and inventory receipts | Upon completion reporting on Mendix, SAP automatically updates the production order completion process and goods receipt. |
In both cases, API calls are made to SAP triggered by business events on the Mendix side, ensuring that on-site operations are reflected in SAP 's core data in real time.
Implementation methods and integration technologies
Mendix offers a high degree of hosting flexibility, supporting deployment on public clouds like Mendix Cloud, as well as on-premises and private cloud environments. Communication with SAP is primarily done via HTTPS/ OData API, with the connection method used depending on the environment as follows:
In terms of authentication and security, it comes standard with mechanisms that meet the standards required in enterprise environments, such as integration with Active Directory/LDAP, single sign-on via SAML and OpenID Connect (OIDC), and access control based on user roles. The interface with SAP is also designed to be protected by authentication tokens and credentials.
The benefits of "extensions that don't change the core"
By adopting this architecture, overseas Mendix implementation support companies cite the following benefits:
Another advantage of this architecture is its resilience to future SAP version upgrades. As long as the connection is via the standard OData API, even if SAP migrates to S/4HANA, the Mendix business logic and UI can be used almost as is. The only part that needs to be rewritten is the OData connection on the SAP side. Choosing to "extend SAP" not only simplifies current development but also protects investments against future SAP version upgrades.
Mendix is an option that "leverages SAP" rather than "replaces SAP."
Extending SAP with Mendix is not about completely overhauling the existing SAP environment, but rather an approach that allows you to quickly add the functions that the end users truly need while keeping SAP 's robust core intact. From the perspective of enterprise system development experience, Mendix is a platform designed with integration with such core systems in mind, and it offers one answer to the question that IT departments often have: "Can it really work in the enterprise domain?"
If you would like to discuss specific configurations and what kind of extensions are possible within your SAP environment, you can contact us through the Mendix product page.