An image tag is a readable name associated with an image reference. Unless a registry policy prevents reassignment, the same tag can later identify another artifact. Tags such as v1.4 and latest differ in naming convention, not in an inherent guarantee of immutability. Reproducing a deployment requires recording the artifact actually selected, together with the platform and runtime configuration that determined its behavior. ...
A staging test establishes facts about the artifact and environment that actually ran. Building again before production creates another output whose identity must be checked or whose behavior must be revalidated. Promotion carries an already verified artifact to the next environment and records that decision. It removes one source of uncertainty, but it does not make staging and production equivalent or eliminate the need to verify the resulting deployment. ...
A dependency version is useful when its publisher and consumers agree on the public contract. Semantic Versioning gives changes a vocabulary: from version 1.0.0 onward, incompatible public API changes require a major increment, compatible additions require a minor increment, and compatible fixes require a patch increment. The number summarizes a claim about a release. It does not inspect its implementation or guarantee that an upgrade will work in your application. ...