Walmart Labs emphasizes the importance of experimentation in its engineering processes, ensuring new features either demonstrate their value or undergo improvement before release. This approach, led by Sonali Sheel, is central to the development of the Walmart Grocery mobile app, which has expanded significantly since its 2013 pilot to nearly every Walmart across the U.S., benefiting around 90% of the population. The team employs two main strategies: "Test to Learn," which focuses on understanding customer behavior and validating hypotheses through iterative testing, and "Test to Launch," which involves gradual feature rollouts to minimize risk and avoid negative impacts on key metrics. By using their custom-built experimentation platform, Expo, Walmart Labs mitigates risks associated with new feature releases while maximizing positive outcomes. This methodology aligns with broader industry practices that advocate for structured experimentation and progressive delivery to ensure features deliver meaningful impact without compromising business metrics.