QA Fundamentals Senior interview questions and answers

76 questions for a QA Fundamentals (Senior) interview - with correct answers, explanations and links to the docs.

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  1. 1.What should an organization-level test strategy define?
  2. 2.A team ships daily, but releases still fail in production. What is usually the most effective first move?
  3. 3.How do you measure the effectiveness of a QA process without rewarding the wrong behaviour?
  4. 4.Which DORA metric relates most directly to release quality?
  5. 5.What is the cost of quality model?
  6. 6.How would you introduce testing into a legacy product with no tests?
  7. 7.When does it make sense to have fewer unit tests and more integration tests?
  8. 8.How should a team decide what NOT to test?
  9. 9.What is a good way to make testers effective in cross-functional teams?
  10. 10.Why are test automation frameworks treated as products?
  11. 11.How do you estimate the ROI of test automation?
  12. 12.What is the main risk of a large UI end-to-end suite as the only safety net?
  13. 13.How would you reduce flakiness across a large test suite?
  14. 14.What does 'testing in production' responsibly involve?
  15. 15.What are synthetic checks?
  16. 16.How do SLOs connect to quality work?
  17. 17.What is chaos engineering?
  18. 18.What should a QA lead check when an A/B test is planned?
  19. 19.How do contract tests change testing in a microservice system?
  20. 20.What is the main challenge of end-to-end test environments for microservices?
  21. 21.What are ephemeral test environments?
  22. 22.How should test data be managed for parallel automated tests?
  23. 23.What does model-based testing do?
  24. 24.What is property-based testing?
  25. 25.What does a mutation score tell you that coverage doesn't?
  26. 26.How do you test a feature that depends on the current date and time?
  27. 27.Which bugs are typical around daylight saving time changes?
  28. 28.What is a characterization test?
  29. 29.How do you test eventual consistency in a distributed system?
  30. 30.How do you test idempotency of a payment API?
  31. 31.What is a quality risk workshop?
  32. 32.Which mitigations besides testing can reduce a product risk?
  33. 33.How do you make a release decision when known bugs remain?
  34. 34.What is the tester's role in a production incident post-mortem?
  35. 35.How should security testing fit into a delivery process?
  36. 36.What is a threat model useful for in testing?
  37. 37.How do you test authorization thoroughly in a multi-role system?
  38. 38.What does a good performance test report include?
  39. 39.Why run soak (endurance) tests?
  40. 40.Why should performance testing start before the end of a project?
  41. 41.How do you test that a system degrades gracefully when a dependency is slow?
  42. 42.What is the main benefit of observability for QA?
  43. 43.How should accessibility be built into a QA process?
  44. 44.How do you test localization at scale across many languages?
  45. 45.What is pseudo-localization?
  46. 46.How should compliance requirements (e.g. GDPR) affect testing?
  47. 47.What is the danger of a test suite that is always green?
  48. 48.How do you decide between manual and automated testing for a new feature?
  49. 49.What makes a good regression strategy for a mobile app with many devices?
  50. 50.How do you test a machine learning feature such as recommendations?
  51. 51.What is the oracle problem?
  52. 52.What is metamorphic testing?
  53. 53.How do you test a data migration?
  54. 54.Why is backward compatibility testing important for APIs and apps?
  55. 55.How should a QA lead respond to pressure to skip testing for a deadline?
  56. 56.What is a test maturity model used for?
  57. 57.Why should testers review pull requests?
  58. 58.What is the main goal of exploratory testing at senior level?
  59. 59.How do you test a system with many configuration options?
  60. 60.What is defect prevention?
  61. 61.How should test results be communicated to non-technical stakeholders?
  62. 62.What is a test automation pyramid anti-pattern known as the 'ice cream cone'?
  63. 63.How does shift-left change a senior tester's daily work?
  64. 64.What is the purpose of a release readiness review?
  65. 65.How do you handle a defect found in production that tests should have caught?
  66. 66.What should be tested in a feature flag rollout plan?
  67. 67.How do you test caching behaviour?
  68. 68.What is a 'test strategy for a third-party integration'?
  69. 69.What is the main risk of relying only on code coverage targets in a team?
  70. 70.What are 'quality attributes' in ISO 25010 terms?
  71. 71.How do you test for resilience to bad network conditions in a web app?
  72. 72.What is the role of exploratory testing in a highly automated pipeline?
  73. 73.What does a mature bug triage process avoid?
  74. 74.How can testers help reduce the cost of flaky infrastructure?
  75. 75.What is a sign that a team's testing is too late in the process?
  76. 76.Why is 'zero bugs found' in a test cycle not automatically good news?