Our application has a dependency on infinispan caches in code. We declare a dependency on the org.infinispan module in our jboss-deployment-structure.xml. We use org.infinispan.Cache in our code. This interface declares methods that take implementations of org.infinispan.util.function.SerializableFunction as parameters. This works fine in WildFly 30, but in 31, the module seems to be setup differently and the new module does not export classes from org.infinispan.util.function. This results in a java.lang.NoClassDefFoundError: org/infinispan/util/function/SerializableFunction. Changing the module dependency to org.infinispan.core fixes this issue, but that module is private.