test-suite-builder

Layered Kotlin Spring tests use a three-layer strategy: unit tests for pure domain logic, slice tests for framework boundaries like controllers and repositories, and selective SpringBootTest with Testcontainers for cross-component integration boundaries.

Balance speed and realism by classifying what needs proving: use fast unit tests for pure business logic, and reserve slower, realistic slice or integration tests for framework boundaries and data-store interactions.

Use slice tests for focused framework boundary checks like HTTP contracts, repository behavior, serialization, and security. Use selective integration tests with Testcontainers only for cross-component integration and actual data-store interactions.

Design reusable fixtures and test data for Kotlin unit tests by establishing clear naming conventions, reusable builders, and structured test data strategies that enable maintainable and reproducible test suites across all testing layers.

Yes, this test strategy framework supports serialization and security testing by recommending targeted slice tests to validate these specific framework boundaries independently from slower cross-component integration tests.

Use Testcontainers for Spring integration tests instead of mocked repositories to ensure realistic regression coverage of actual data-store interactions and cross-component integration boundaries that mocks cannot accurately replicate.