What is the STLC and what are its phases?
60-second answer
STLC, the Software Testing Life Cycle, is the sequence of testing activities inside the SDLC. It has six phases: requirement analysis, where we study what to test; test planning, where we define scope, approach, resources and schedule; test case design, where we write test cases and prepare data; test environment setup; test execution, where we run tests and log defects; and test closure, where we report results and lessons learned. Each phase has entry and exit criteria.
Explanation
| Phase | Key output |
|---|---|
| Requirement analysis | Testable requirements list, RTM draft, questions to BA |
| Test planning | Test plan, effort estimate, tool choice |
| Test case design | Test cases, test data, automation scripts |
| Environment setup | Ready test environment, smoke test passed |
| Test execution | Execution results, defect reports |
| Test closure | Test summary report, metrics, lessons learned |
Entry criteria say when a phase can start (for example, a build is deployed and smoke-tested). Exit criteria say when it's done (for example, all critical tests pass and no open P1 defects).
Example
For a new "Add to wishlist" feature: analyse the story, plan to cover web and mobile, write 15 test cases, wait for the QA environment, execute and log 3 bugs, then send a summary to the product owner.
Sample code
Analyse -> Plan -> Design -> Set up env -> Execute -> Close