SAP BTP Reference Architectures and Extension Placement

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Extension placement and design review card

• Start from a reference architecture; record its title, date and your deviations.
• Must it act inside an SAP transaction? On-stack. Other users, systems or BTP services? Side-by-side.
• Use released APIs and business events; side-by-side is only clean if its interfaces are.
• Pick the identity pattern per call: principal propagation for internal users, narrow technical user plus app checks otherwise.
• Reach private systems through the Cloud Connector; harden it and run it highly available.
• Name a run owner; set up health, integration and user monitoring in SAP Cloud ALM with routed alerts.
• Build in retries with backoff, timeouts, caching and a circuit breaker.
• Define contracts and test layers; keep security filters unit-testable.
• Pipeline runs fast tests on every change; integration and end-to-end run in the test and pre-production stages.