The Identity Registry includes many software components, each of which may carry its own version number. However, the only version we publish to customers is an overall version for the Registry as a whole.

When we deploy software to the Identity Registry, we will communicate the new version. Version numbers follow the Semver standard of major.minor.patch-extension and are intended to help customers understand the kind of change and potential impact that may be involved. 

Major

• An increment to the major version indicates a change that is not backwards compatible with the existing customer contract.
• Major version changes may include new features, patches, and removal of deprecated features.
• When a major version is incremented, the minor and patch version are reset to 0.
• Major version changes are rare.

Minor

• An increment to the minor version indicates new features that are backwards compatible with the existing customer contract.
• Minor version changes may also include patches.
• When a minor version is incremented, the patch version is reset to 0.
• Minor version changes are common.

Patch

• An increment to the patch version indicates backwards compatible bugfixes only.
• Bugfixes restore intended design when the customer contract has been inadvertently broken. 
• Patch version changes are common.

Extension

• Identity Registry uses extensions to communicate release candidate (rc) status for pre-production versions.
• The first release candidate for intended production version 4.5.2 would be 4.5.2-rc1, the second would increment to 4.5.2-rc2, etc.
• Once a version is released to production, the extension is removed.
• If a problem is detected after production release of 4.5.2, work would begin on 4.5.3 to fix the issue. 4.5.2-rc3 would not be used.