More than 100 interfaces, three plants, live JIT supply: an automotive supplier was moving to SAP S/4HANA. The risk was not the ERP but the point-to-point integration that had grown over years. We helped turn it into one central layer on CPI. The go-live landed on schedule.
More than 100 interfaces. Three plants. OEMs supplied just in time while the ERP underneath gets replaced. What breaks first?
That was the question facing an automotive supplier on its way to SAP S/4HANA. The risk was not the ERP itself but the integration: grown over years, point-to-point, barely documented. We joined the project team to help turn that tangle into a central integration layer on the SAP Integration Suite (CPI). The go-live landed on schedule.
Over the years, the integration had grown one connection at a time: point-to-point, every system wired straight to the next. By the end there were more than 100 interfaces between S/4HANA, MES, warehouse and transport systems, the OEM EDI connection and over 20 further applications, spread across three plants.
Lifting that grown wiring onto S/4HANA without disrupting just-in-time supply was the real task. And it did not run in isolation: several implementation partners and internal IT worked on the same system in parallel.
We came in to reinforce the integration workstream, focused on the interface architecture. The plan was simple: away from direct wiring, toward one layer that everything runs through.
We built that layer on the SAP Integration Suite (CPI). Instead of dozens of direct connections there is now a manageable set of standardised, versioned interfaces with clear contracts. Extensions sit next to the core as side-by-side extensions, not inside it. That is the Clean Core idea, and it keeps the S/4HANA system upgradable.
The work ran as its own stream over roughly eight months, from target architecture to go-live.
Mapping the grown connections, one clear target picture and a prioritised list of every interface.
Fixed patterns for CPI, plus naming, versioning and extension rules every team follows.
Building and testing the interfaces on CPI, together with the other vendors on the project.
Planning the switchover, arming the monitoring and handing operations cleanly to the internal team.
The go-live happened on schedule. The web of direct connections gave way to a central layer where every interface is visible, monitored and versioned in one place.
The biggest difference shows up in everyday operations afterwards. When an interface gets stuck, you see it in the monitoring straight away, instead of searching through dozens of connections. When an OEM changes its EDI format, you adjust it in one place. And the S/4HANA system stays clean and upgradable.
That this step pays off beyond a single project is shown by a Forrester study commissioned by SAP: companies achieved a 345 percent ROI over three years with SAP Integration Suite, and integration developer efficiency rose by 30 percent.
At a supplier, the customers' production depends on reliable delivery. Delivery schedules, cumulative quantities and just-in-time sequences have to flow reliably between OEM, ERP, MES and warehouse logistics. If the wrong interface breaks, in the worst case a line stops at the customer.
That is why standardisation was not an end in itself. Clean, versioned interfaces and central monitoring are what make a cutover across more than 100 connections plannable instead of a gamble.
Not every landscape needs this step. Four questions show whether it pays off.
How many interfaces are there, really? The more systems hang together through the more connections, the bigger the gain in clarity and reuse.
How many plants or tenants are involved? As soon as the same interface exists more than once, standardisation pays off twice.
How often do external formats change? If OEM EDI changes regularly, you want to adjust it in one place, not twenty.
Is Clean Core on the agenda? Staying upgradable takes extensions next to the core, not inside it.
If you only have a handful of stable connections that rarely change, a central layer can be a sledgehammer to crack a nut. An honest look at interface count, rate of change and plant structure usually settles the decision.
We know both sides: SAP in depth, and the integration world of manufacturing. S/4HANA, MES and logistics connectivity, OEM EDI, the SAP BTP. You can find an overview of our services under SAP Consulting, and another project in our reference on material master creation at a machinery manufacturer. And on every project, a founder sits at the table, not a pyramid of juniors.
Planning an S/4HANA move and want the integration to hold rather than become a risk? Let's talk for 30 minutes. Concrete, no sales pressure.
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