Feature Lifecycle

Crossplane follows a similar feature lifecycle to upstream Kubernetes. All major new features must be added in alpha. Alpha features are expected to eventually graduate to beta, and then to general availability (GA). Features that languish at alpha or beta may be subject to deprecation.

Alpha Features

Alpha are off by default, and must be enabled by a feature flag, for example --enable-composition-revisions. API types pertaining to alpha features use a vNalphaN style API version, like v1alpha. Alpha features are subject to removal or breaking changes without notice, and generally not considered ready for use in production.

In some cases alpha features require fields be added to existing beta or GA API types. In these cases fields must clearly be marked (i.e in their OpenAPI schema) as alpha and subject to alpha API constraints (or lack thereof).

All alpha features should have an issue tracking their graduation to beta.

Beta Features

Beta features are on by default, but may be disabled by a feature flag. API types pertaining to beta features use a vNbetaN style API version, like v1beta1. Beta features are considered to be well tested, and will not be removed completely without being marked deprecated for at least two releases.

The schema and/or semantics of objects may change in incompatible ways in a subsequent beta or stable release. When this happens, we will provide instructions for migrating to the next version. This may require deleting, editing, and re-creating API objects. The editing process may require some thought. This may require downtime for applications that rely on the feature.

In some cases beta features require fields be added to existing GA API types. In these cases fields must clearly be marked (i.e in their OpenAPI schema) as beta and subject to beta API constraints (or lack thereof).

All beta features should have an issue tracking their graduation to GA.

GA Features

GA features are always enabled - they cannot be disabled. API types pertaining to GA features use vN style API versions, like v1. GA features are widely used and thoroughly tested. They guarantee API stability - only backward compatible changes are allowed.