I have an update to this question. When i deploy the module without maven its working with this dependencies in the module.xml: <dependencies> <module name="org.keycloak.keycloak-core"/> <module name="org.keycloak.keycloak-server-spi"/> <module name="org.keycloak.keycloak-server-spi-private"/> <module name="org.keycloak.keycloak-services"/> </dependencies> So I think the problem is the combination of wildfly-maven-plugin and the keycloak-services dependency. Maybe maven does not provide the right dependencies for the module? Is there a way to debug which dependencies are defined for my module if I deploy it via wildfly-maven-plugin? Do I need another maven plugin to make it work? At the moment I have the plugins defined in the quickstart repository: <plugin> <groupId>org.wildfly.plugins</groupId> <artifactId>wildfly-maven-plugin</artifactId> <version>1.1.0.Final</version> <configuration> <skip>false</skip> </configuration> </plugin> <plugin> <groupId>org.jboss.as.plugins</groupId> <artifactId>jboss-as-maven-plugin</artifactId> <version>7.4.Final</version> <configuration> <skip>false</skip> </configuration> </plugin> Cheers, Felix -----Ursprüngliche Nachricht----- Von: keycloak-dev-bounces(a)lists.jboss.org <keycloak-dev-bounces(a)lists.jboss.org&gt; Im Auftrag von Felix Peters Gesendet: Dienstag, 13. März 2018 21:36 An: keycloak-dev(a)lists.jboss.org Betreff: [keycloak-dev] Maven dependencies for custom ActionToken implementation Hi, i try to implement a custom ActionToken. I want to deploy the Module via wildfly-maven-plugin. This works like expected. No errors when i run "mvn clean install wildfly:deploy". But when i try to instantiate a ActionToken i get the following exception: Uncaught server error: java.lang.NoClassDefFoundError: Failed to link my/package/actiontoken/TestActionToken (Module "deployment.keycloak-actiotokentest-1.0-SNAPSHOT.jar" from Service Module Loader): org/keycloak/authentication/actiontoken/DefaultActionToken In my pom.xml i have this dependencies for Keycloak: <properties> <keycloak.version>3.4.3.Final</keycloak.version> </properties> <dependency> <groupId>org.keycloak</groupId> <artifactId>keycloak-core</artifactId> <scope>provided</scope> <version>${keycloak.version}</version> </dependency> <dependency> <groupId>org.keycloak</groupId> <artifactId>keycloak-server-spi</artifactId> <scope>provided</scope> <version>${keycloak.version}</version> </dependency> <dependency> <groupId>org.keycloak</groupId> <artifactId>keycloak-server-spi-private</artifactId> <scope>provided</scope> <version>${keycloak.version}</version> </dependency> <dependency> <groupId>org.keycloak</groupId> <artifactId>keycloak-services</artifactId> <version>${keycloak.version}</version> </dependency> In the quickstart example (https://github.com/keycloak/keycloak-quickstarts/blob/latest/action-token...) they have the keycloak-services dependency not in the provided scope. I tries to use this scope and i removed it. But i always get the same error. So what dependencies do i have to define if i want to implement a custom ActionToken? I think it's the keycloak-services, but i can't find details about that. Is the keycloak-services a provided artifact or not? Thanks for your help, Felix _______________________________________________ keycloak-dev mailing list keycloak-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/keycloak-dev