Risk-based scoping, entry and exit criteria, estimation, traceability, and release sign-off judgement.
3 questions in QA & Testing.
Automate what runs often, has a deterministic oracle, sits on a stable interface, and guards an expensive escaped bug. Push each check to the cheapest layer that can still fail meaningfully, treat flakiness as a defect rather than noise, and keep human time for exploratory testing, not scripted regression.
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.
A clean track record is evidence about the old system's operating envelope, not about yours, so the strategy must surface the assumptions the component inherits, test it against the new envelope rather than trusting its history, and state which inherited assumptions are going untested.