Mule Upgrades and Patch Updates
MuleSoft continuously improves the quality, capabilities, and security of Mule runtime engine (Mule). In addition to upgrading to later versions of Mule, it also is important to apply regular updates to the Mule versions (such as versions 3.9.5, 4.1.5, and 4.3.0) on which you are running your Mule applications.
Be sure to review the information on updates, upgrades, versioning, and testing before attempting to upgrade or apply a patch update.
Patch updates are cumulative releases that include the latest bug fixes and security enhancements to a specific patch (x.y.z) version, plus all previously released features and fixes for that patch version. For updates, see Update Patches to Mule.
Unlike the patch update process, the Mule upgrade process is for upgrading to a later version. For example, you can upgrade from Mule 4.x to 4.y (such as 4.3.0 to 4.4.0) or Mule 4.x.y to 4.x.z (such as 4.2.1 to 4.2.2). For minor and patch version upgrades or a major version migration, see:
Though Mule guarantees compatibility with new minor, patch, or patch update versions, it is important to validate that your applications continue to run as expected in a testing environment before running them in a production environment.
Run your MUnit tests on any new version of Mule to validate the application’s behavior with that version.