Custom developments: What to do before switching to SAP S/4HANA

With the help of customer-specific developments, companies are able to adapt the SAP ERP system to their own needs and modify the standard processes according to their specific requirements. In the context of the changeover to SAP S/4HANA, companies face a particular challenge with regard to their custom developments: Many customer-specific extensions cannot be transferred one-to-one to SAP S/4HANA – for various reasons.

5 golden rules for handling your custom developments during migration to SAP S/4HANA

Why companies need to address their custom developments

For example, it is possible that certain programming interfaces are no longer supported or that the previous SAP ERP system uses approaches that no longer work with SAP HANA database. In addition, some functionalities that were mapped by custom developments in the past are now included in the SAP S/4HANA standard, making the extensions obsolete. And it is likely that custom developments which the company no longer uses at all have accumulated in the historically grown ERP system, which has already been in use for several years or even decades.

Thorough analysis of custom developments

Before companies switch to SAP S/4HANA, they should conduct a thorough inventory with a view to their custom developments and analyze them with regard to necessity and compatibility with SAP S/4HANA. In this way, companies can ensure that their business processes will continue to function smoothly in the future. The following questions are relevant for the analysis of the customizations:

• Which custom developments are still being used? Which ones can be abandoned during the migration to SAP S/4HANA?

• Which customer-specific extensions are available in the SAP S/4HANA standard and are accordingly no longer required?

• Which adjustments are required to bring the existing custom developments to SAP S/4HANA?

• Is the effort for migration worth it or is another approach, for example connection as a side-by-side extension on SAP Business Technology Platform, more sensible?

Evaluating custom developments from multiple perspectives

To get the right answers to these questions, a best-practice approach involving several steps has proven effective. The first step is a thorough review of customer-specific modifications with regard to their use. Extensions that are no longer used in the company can be sorted out. It should be noted that some extensions are rarely used, for example only during the year-end closing process. In such cases, however, the frequency of use says nothing about the importance of the extension for the business processes.

Furthermore, it is advisable to analyze the custom developments with regard to the “fit-to-standard”: Does SAP S/4HANA possibly already cover the desired functionality in the standard, so that an extension is no longer required? It is also relevant to check the migratability of the custom developments. If it is possible to migrate the extensions to SAP S/4HANA without a great deal of effort, an implementation as an on-stack or in-app extension is a good option. If, on the other hand, migration proves to be disproportionately complex, it makes more sense to implement the functionality as a side-by-side extension. Licensing aspects must also be considered when making this decision: If external users outside the own company need access to the extension, this speaks for a side-by-side extension. In this way, companies can keep the number of ERP users small and save money with the SAP Digital Access licensing program.

Differentiate from the competition with extensions

Reviewing and cleaning up custom developments has a beneficial effect on companies’ individual business processes. While standard functionalities are covered by SAP software, companies can focus on extensions that bring real competitive advantages. This approach saves time and money in the implementation of customer-specific extensions. Existing know-how within the company can be used for in-app or on-stack enhancements. Side-by-side extensions enable the integration of new user groups such as suppliers, customers and partners. Because these types of extensions are detached from the SAP S/4HANA digital core, they have a separate lifecycle and bring a high degree of agility.

Conclusion: Unleash the potential of custom developments

Dealing with custom developments is an important task for companies in the run-up to the SAP S/4HANA migration. They should take the opportunity to tidy up the extensions and modifications that have often grown historically and check which custom developments are actually still needed and whether they are compatible with SAP S/4HANA. Careful planning and analysis minimizes the effort and costs involved in moving customer-specific developments. At the same time, companies have the opportunity to focus on those extensions that set them apart from the competition.