Proceedings of the International scientific and practical conference ―The Hague Conference on Science and Public Policy‖ (May 8-10, 2026) / Publisher website: www.naukainfo.com. – The Hague, Netherlands, 2026. - 232 p.

30 The modern landscape of enterprise software testing has evolved beyond isolated functional checks, shifting toward comprehensive E2E scenarios that mirror complex real-world user journeys. In such environments, a single business process often begins with a backend service call and concludes within a native desktop application on Windows or macOS. The primary challenge of automating these chains lies in the heterogeneity of the technology stacks and the need for seamless state synchronization across disparate interfaces. A robust strategy for unified verification starts at the data layer. Instead of relying on manual pre-conditions or fragile UI-based setup, the automation framework utilizes API calls to perform "just-in-time" data initialization. By leveraging libraries such as RestSharp [1] or Microsoft HttpClient [2], the system can programmatically create users, configure permissions, or inject specific transaction records into the backend. This ensures that the subsequent desktop automation phase, driven by Appium or WinAppDriver, starts in a deterministic environment, significantly reducing the likelihood of "flaky" results caused by stale or inconsistent data. The core of this cross-platform strategy is the orchestration of the test flow across different execution drivers within a single C# .NET project. For instance, a scenario might involve triggering a server-side event via an API request and then verifying the real-time notification delivery within a Windows desktop client. The framework must handle the transition between these layers, managing session lifetimes and ensuring that the desktop interface is polled for updates only after the backend has confirmed the processing of the initial request. This synchronized approach prevents synchronization bottlenecks and ensures that the automation suite remains performant even as the complexity of the E2E chain increases. Furthermore, a unified strategy necessitates a common reporting and diagnostic layer. When a failure occurs, the framework should provide a correlated view of the logs from all involved layers: the HTTP request/response payloads from the API and the UI tree state from the desktop application. This holistic visibility is crucial for root cause analysis in heterogeneous environments, allowing engineers to quickly