You work on a payments product where the team has built a new feature in the checkout installment flow intended to improve customer conversion. Stakeholders want to know whether the feature should launch broadly, but you need a rigorous experiment design that balances growth with risk to approval quality and customer experience.
Walk me through how you would approach A/B testing this new feature. How would you decide what to measure, how long to run the test, and whether the results are strong enough to ship?