I believe that they are using Semantic Versioning 2.0.0[1] as discussed in the Swift Package Manager Project&#x27;s Website[2] under &quot;Importing Dependencies&quot;:<p>&gt; Given a version number MAJOR.MINOR.PATCH, increment the:<p>&gt; MAJOR version when you make incompatible API changes,<p>&gt; MINOR version when you add functionality in a backwards-compatible manner, and<p>&gt; PATCH version when you make backwards-compatible bug fixes.<p>&gt; Additional labels for pre-release and build metadata are available as extensions to the MAJOR.MINOR.PATCH format.<p>[1] Semantic Versioning 2.0.0 <a href="http:&#x2F;&#x2F;semver.org" rel="nofollow">http:&#x2F;&#x2F;semver.org</a><p>[2] Swift.org - Package Manager <a href="https:&#x2F;&#x2F;swift.org&#x2F;package-manager&#x2F;" rel="nofollow">https:&#x2F;&#x2F;swift.org&#x2F;package-manager&#x2F;</a>