Brew follows a rolling-release style, it behaves the same way the Arch Linux package manager does. In Arch users are discouraged from upgrading specific package

Brew follows a rolling-release style, it behaves the same way the Arch Linux package manager does. In Arch users are discouraged from upgrading specific packages instead of everything as a whole. That said, the docs say that running "brew upgrade <package>" will only upgrade that specific package. Of course, if that package relies on new versions of dependencies, they will get updated too, and in turn this will update any packages that also depend on it, creating a chain of updates. But there's an option to see what will happen: "brew upgrade --dry-run <package>".