Top 4 Integration testing Interview Questions
Browse 4 real-world technical and behavioral interview questions about Integration testing. Review scenarios, edge cases, and architectural best practices.
Your consumer-driven contract test passes in CI, but production rejects a request because a supposedly optional field is missing. What did the contract testing actually miss?
The contract captured the shape the consumer sends, not the rules the provider enforces. Optionality lived in the schema while the real requirement lived in provider validation, and no recorded example ever omitted the field. Contract tests only verify interactions they contain, so add the negative example and verify against real code.
How do you test a Node service, and what do you refuse to mock?
Drive business logic through injected dependencies rather than module mocks, intercept at the process boundary for outbound HTTP and time, and use a real database in a container for anything where the database is the logic — SQL, constraints, transactions and migrations.
No environment in the estate contains the whole stack, so nobody can test an order end to end before release. How do you get assurance anyway?
Stop trying to build one environment containing eight vendors' products. Pin every boundary with a contract test each side can run alone, simulate the network, keep a small high-fidelity path for whole journeys, and put continuous synthetic orders through production as the real assurance.
What is the test pyramid, and is it still the right model for your system?
Buy most of your confidence from fast isolated tests and little from slow end-to-end ones, because cost and flakiness rise as you climb. It is a claim about where risk lives, so a system whose risk sits in integration - a thin service over a database - correctly has a different shape.