The phase of software design that integrates individual code components and verifies their interoperability isTesting, specifically integration testing. After developers write and unit-test individual modules, those modules must be combined into a complete system. The testing phase ensures that these modules communicate properly, data flows correctly, and overall functionality meets requirements.

Planning establishes project goals, coding builds individual components, and training prepares users. None of these directly verify interoperability. Testing is critical because even well-functioning components may fail when combined, due to interface mismatches, unexpected data structures, or dependency issues.

Cloud-based systems often integrate microservices, APIs, and third-party services. Testing validates that these distributed components interact seamlessly. Proper testing reduces defects, supports reliability, and ensures a consistent end-user experience. It also aligns with DevOps practices, where continuous integration and automated testing pipelines quickly identify and remediate interoperability issues.