nginx does not assign a general specificity score to every location expression. Ordinary prefixes are selected by matching length, exact locations can finish the search, and competing regex locations are evaluated in declaration order. A regex that looks narrower to a human can lose to a broader expression placed earlier. Mixing these selection rules is a common reason apparently careful routing changes affect unexpected paths. ...
A ConfigMap stores non-confidential configuration separately from an image. That lets a release change an environment-specific value without rebuilding the application artifact. The useful boundary is explicit: the image supplies code, while the workload definition identifies which configuration that code should consume. A release is therefore more than an image tag; its configuration reference is part of the behavior being deployed. ...
An environment file separates deployment values from the unit definition that describes process supervision. systemd reads the configured file before executing a service command and supplies those values in that process’s environment. Editing the file does not rewrite the environment of an already running process. A reload helper is another process, however, and can receive newer file values than the service’s existing main process. ...