Implementing Event-Driven Customizations in ERP Systems

After years building event-driven systems. Here are the top 4 mistakes I have seen: 1. Duplication Events often get re-delivered due to retries or system failures. Without proper handling, duplicate events can: • Charge a customer twice for the same transaction. • Cause duplicate inventory updates, messing up stock levels. • Create inconsistent or broken system states. Solution: • Assign unique IDs to every event so consumers can track and ignore duplicates. • Design event processing to be idempotent, ensuring repeated actions don’t cause harm. 2. Not Guaranteeing Order Events can arrive out of order when distributed across partitions or queues. This can lead to: • Processing a refund before the payment. • Breaking logic that relies on correct sequence. Solution: • Use brokers that support ordering guarantees (e.g., Kafka). • Add sequence numbers or timestamps to events so consumers can detect and reorder them if needed. 3. The Dual Write Problem When writing to a database and publishing an event, one might succeed while the other fails. This can: • Lose events, leaving downstream systems uninformed. • Cause mismatched states between the database and event consumers. Solution: • Use the Transactional Outbox Pattern: Store events in the database as part of the same transaction, then publish them separately. • Adopt Change Data Capture (CDC) tools to track and publish database changes as events automatically. 4. Non-Backward-Compatible Changes Changing event schemas without considering existing consumers can break systems. For example: • Removing a field might cause missing data for consumers. • Renaming or changing field types can trigger runtime errors. Solution: • Maintain versioned schemas to allow smooth migration for consumers. • Use formats like Avro or Protobuf that support schema evolution. • Add adapters to translate new schema versions into older ones for compatibility. "Every schema change is a test of your system’s resilience—don’t fail it." What other mistakes have you seen out there?

You find the perfect room on Airbnb... You click “Book Now.” Payment done. Then comes that email: "Sorry, the room is already booked." 😤 The frustration is real. 💡 So how do platforms like Airbnb or Booking.com solve this? - Rooms listed by hosts appear instantly to customers — no page reloads needed. - If one customer starts payment, the room disappears from others' search results. - If the payment fails or times out, the room is released back into availability. All this happens in real-time, without breaking the user experience. ✅ The answer: Event-Driven Architecture Here’s how i tried to recreate in my SAP-based design: 🔹 Customer searches for rooms → Search Service checks real-time availability via SAP Event Mesh 🔹 Customer picks a room → Booking Service reserves it in Redis (temporary hold for 10 minutes) 🔹 Booking Service publishes an event → Room marked as on-hold 🔹 Hotel Service updates availability → Everyone else sees 1 less room 🔹 Payment Service completes transaction → - Success → Room confirmed in S/4HANA Cloud - Fail/Timeout → Room released, event broadcasted 🎯 Why this system design: ✅ Prevents double bookings ✅ Keeps availability always accurate ✅ Uses Redis for smart, temporary caching ✅ Integrates with S/4HANA Cloud for backend ops (HR, finance, procurement) ✅ SAP Document Management can store images, invoices, and more This is a real-world case for event-driven microservices done right — blending customer experience with enterprise robustness. #SAPBTP #EventDrivenArchitecture #Microservices #Redis #S4HANA #SAPCAP #SAPEventMesh #DesignThinking #CustomerExperience

I've watched too many organizations conduct excellent Event Storming sessions—capturing domain events, workflows, pain points—only to struggle when implementing event-driven architecture. The gap isn't technical capability. It's the missing translation layer between business domain language and distributed systems architecture. Your Event Storm wall shows you everything you need: - Yellow sticky notes reveal which events matter to cross-system workflows - Blue command notes map to event triggers - Process sequences show event choreography dependencies - External system notes identify integration points But without a structured approach to translate these artifacts into event schemas, producers, consumers, and channels, you end up with architectures disconnected from the domain knowledge you just captured. Amárach StackWorks's latest article breaks down the bridge: how Event Storm discoveries map to event-driven patterns, and the practical steps to avoid architectural purgatory. This is about opening your event-driven architecture properly—starting with business events, not technology choices. Worth reading if you're implementing EDA or trying to connect Event Storming results to actual systems. #EventDrivenArchitecture #EventStorming #Manufacturing #DigitalTransformation #ISA95

🚀#Event #Mesh in #SAP #BTP #CPI #Event #Mesh is a #feature in #SAP #CPI that supports #event-#driven #integration between different #systems. #Essentially, it's a #messaging #layer that allows different #applications or #systems to #communicate by #sending and #receiving #events (#changes or #updates in #data) in #real #time, #rather than #relying on #traditional #request / #response #integrations. Imagine you have #multiple #systems, like #SAP #S4HANA for #order #management and #SAP #SuccessFactors for #employee #data. Instead of having these #systems constantly check each other for #updates, #Event #Mesh allows them to #communicate through #events. So, when something important happens, like a #new #order #being placed in #S4HANA, it #triggers an #event that other #systems (like #CPI, #SuccessFactors, or any other connected systems) can listen to and react to in real time. 🔎How it works ✅#Event #Publisher-When something happens in a #system, like a #new #order being created in #SAP #S4HANA, that system becomes the #event #publisher. It sends out an #event to the #Event #Mesh. ✅#Event #Consumer-Other #systems that are interested in that #event, like #SAP #CPI or #SuccessFactors, act as #event #consumers. They listen for specific events and take #action when they occur. For example, when the "#new #order" #event is received by #CPI, it could #trigger a process to update employee records in #SuccessFactors. ✅#Loose #Coupling-One of the best things about #Event #Mesh is that it decouples the systems. The #publisher (e.g., #SAP #S4HANA) doesn’t need to know who’s consuming the #event, and vice versa. This makes the systems much more flexible and scalable because if you need to add or remove systems, it doesn’t disrupt the entire process. ✅#Reliability- #Events are reliably delivered, even if one of the systems is temporarily unavailable. If the consuming system is down, the #event will be #queued and #processed when the system is back #online. This ensures no #data is lost. 🔎#Importance? This #approach makes #integrations much more #real-#time and #responsive. Instead of waiting for #periodic #updates or #batch #jobs, #systems can act immediately when something happens. It's perfect for scenarios where #speed and #efficiency are #important-like #handling #real-#time #customer #orders or #responding to #inventory #updates. 📌#Use #Case Let’s say a new order is placed in #SAP #S4HANA. Instead of waiting for a #scheduled #job to send that #order to another #system, #Event #Mesh will instantly #trigger an #event. #SAP #CPI can consume that #event and send the #order details to an external #order #management system or even #trigger an update in #SAP #SuccessFactors if necessary. 📌#Finally So, #Event #Mesh in #SAP #CPI helps systems communicate in a #decoupled, #real-#time way by sending and consuming #events. It makes #architecture more #scalable, #reliable, & #responsive, which is especially important in today’s #fast-#moving #business #environments.

⚡ Business Events in RAP The ABAP RESTful Application Programming Model (RAP) goes beyond building modern transactional apps — it helps you design intelligent, event-driven applications that can automatically trigger reactions when something important happens. This is made possible through Business Events, a core RAP feature that supports Event-Driven Architecture (EDA) natively. 💬 What is Event-Driven Architecture? In an event-driven setup, applications don’t directly call each other. Instead, one system publishes an event, and other systems subscribe to it. For example: When a Purchase Requisition is created, your RAP application can raise an event called PurchaseRequisitionCreated. Other systems — such as approval workflows, budget checks, or notification services — can subscribe to this event and react automatically. There’s no waiting, no dependency — just smooth, asynchronous communication. Here’s how it works step-by-step 👇 🔹 Step 1: Define the Event In the Behavior Definition of your RAP Business Object, you define the event name. This tells RAP that your BO can raise a specific event, such as PurchaseRequisitionCreated or PurchaseOrderApproved. 📘 Think of this as declaring what kind of event your object can publish. 🔹 Step 2: Implement (Raise) the Event In the Behavior Implementation, you raise the event after the data is successfully saved to the database — usually in the late save phase. 📘 This ensures the event only triggers once the transaction is confirmed and no rollback can occur. 🔹 Step 3: Bind the Event Next, you create an Event Binding in ADT (ABAP Development Tools). This artifact connects your RAP event to a namespace and business operation (like MODIFY or DELETE). 📘 This binding makes your event visible to external systems or SAP Event Mesh so it can be consumed. 🔹 Step 4: Publish and Consume Once bound, your event can be published to services such as SAP Event Mesh or Enterprise Event Enablement. Other applications — inside or outside SAP — can subscribe to it and trigger follow-up actions automatically. 📘 For example, when a Purchase Requisition is created, a workflow or notification system can react instantly. #SAPRAP #ABAPonHANA #RAPFramework #EventDrivenArchitecture #BusinessEvents #SAPBTP #SAPDevelopers