3.3.3 Software Migrations Experiments can be used to help with software migration. If a feature or a system is being migrated to a new backend, new database, or a new language, but is not expected to change uservisible features, an A/B test can be executed with the goal of retaining the Null Hypothesis, which is that the variants are not different. We have seen several such migrations, where the migration was declared complete, but an A/B test showed significant differences in key metrics, helping identify bugs in the port. Because the goal here is to retain the Null Hypothesis, it is crucial to make sure the experiment has enough statistical power to actually reject the Null Hypothesis if it false