Integrations belong on BTP, not inside the SAP system
Every custom Z programme, user exit and enhancement that carries an interface has to be retested, and often rewritten, at each upgrade. Put the logic on SAP Integration Suite instead, talk to released APIs and standard IDoc types, and the upgrade stops being a project.
- Mapping and transformation live in iFlows, not in ABAP exits
- Released OData and standard IDoc types rather than direct table reads
- Existing core-embedded interfaces identified and moved out first