Config drift

A gradual, often unnoticed divergence between the configuration of different environments (such as development, staging, and production) that causes tests to behave differently depending on where they run. Config drift is one of the common causes of environment-related test failures, and a key cluster to look for when triaging automated test results. It can manifest as a service that behaves differently in CI than locally, a feature flag set differently across environments, or a third-party dependency pointing to a different endpoint.