New and changed features for Liberty

This release introduces key enhancements and updates to WebSphere® Application Server Liberty.

What's new in Liberty

Liberty now follows a continuous fix pack delivery process and has a numbering scheme of Y.R.M.F, or year, release, modification, and fix pack. Also, new common IBM® Java™ SDKs are available so you can get security and other Java updates faster.

For more information, see What is new in this release of Liberty.

Changed features and feature capabilities

With the Liberty zero-migration policy, no features are ever deprecated or removed. When you update to a newer Liberty version, you can continue to use your existing configuration and applications, with no unexpected change in behavior.

As new technologies become available, existing features and feature capabilities might be marked as discontinued, stabilized, or superseded. You do not need to change any of your existing applications and scripts, but if a strategic alternative is available, consider using the alternative for new applications.

Discontinued feature capabilities

A feature capability that is marked as discontinued will not be available in new versions of a feature. For example, if a capability is discontinued after feature-1.0, the capability will not be available in feature-1.1, but you can continue to use the capability with feature-1.0.

For information about feature capabilities that are discontinued, see Discontinued Liberty feature capabilities.

Stabilized features or feature capabilities

If a feature or feature capability is stabilized, IBM does not currently plan any further enhancements to the feature or feature capability, and future investment will be focused on the strategic alternative.

For information about features and feature capabilities that are stabilized, see Stabilized Liberty features and feature capabilities.

Superseded features

If a feature is superseded, a new feature or a combination of features might provide an advantage over the superseded feature.

For example, new, finer-grained features might be used in place of the superseded one to reduce the server footprint by excluding content that might not be necessary. The new feature or features might not completely replace the function of the superseded feature, so you must consider your scenario before you decide whether to change your configuration. Superseded features remain completely supported and valid for use in your configuration, but you might be able to improve your configuration by using the newer features.

For information about features that were superseded, see Superseded Liberty features.

Removal notices

When items such as Liberty runtime packaging, Java prerequisites, and supported software become outdated, a removal notice can be issued for them. A removal notice signifies that the item can be removed, typically no sooner than two years from the time the notice was issued. No features or other functions that affect the Liberty zero-migration policy are ever removed.

For a list of removal notices, see Removal notices.