Semantic Versioning, or SemVer, specifies how to number software releases using three numbers (e.g. 1.2.6) instead of two (e.g. 1.2). In this presentation, we walk you through the Semantic Versioning numbering system now being used by a number of software projects, now including Drupal 8. This presentation may be viewed as a video at https://drupalize.me/videos/semantic-versioning and is produced by Drupalize.Me.

1. Semantic Versioning
A Software Release Numbering System

2. In This Tutorial
‣ Explain what Semantic Versioning is
‣ List the benefits
‣ Find more information

3. Semantic Versioning
‣ SemVer for short
‣ Uses three numbers for version instead of two
‣ Requires a public API

4. The Numbers
8.2.6
Major version
Minor version
Patch

5. The Numbers
8.2.6
Major version
Minor version
Patch
Major changes
Breaks the API

6. The Numbers
8.2.6
Major version
Minor version
Patch
Major changes
Breaks the API New features
Does not break API

7. The Numbers
8.2.6
Major version
Minor version
Patch
Bug fixesMajor changes
Breaks the API New features
Does not break API

8. The Numbers
8.2.6
Major version
Minor version
Patch
Bug fixesMajor changes
Breaks the API New features
Does not break API

9. Bug Fix
8.2.7

10. New Feature
8.3.0

11. Breaking the API
9.0.0

12. Pre-release Versioning
‣ Initial development uses Major version 0 (e.g. 0.1.0)
‣ You may use pre-release strings (e.g. alpha1, rc3, etc.)
• These are appended to the end (e.g. 1.0.0.alpha1)
‣ A publicly-released API starts at 1.0.0

13. Benefits of Semantic Versioning
‣ Clearer compatibility/dependencies
‣ Encourages well-defined APIs
‣ Makes upgrade decisions clearer

14. Specification
http://semver.org