diff --git a/api/pom.xml b/api/pom.xml
index be94a16a..c8b2813c 100644
--- a/api/pom.xml
+++ b/api/pom.xml
@@ -57,14 +57,13 @@
             <artifactId>jakarta.json-api</artifactId>
         </dependency>
 
-        <!-- test -->
-
         <dependency>
             <groupId>io.smallrye</groupId>
             <artifactId>jandex</artifactId>
-            <scope>test</scope>
         </dependency>
 
+        <!-- test -->
+
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
@@ -137,6 +136,12 @@
             <scope>test</scope>
         </dependency>
 
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <scope>test</scope>
+        </dependency>
+
     </dependencies>
 
     <build>
diff --git a/api/src/main/java/org/fuin/esc/api/HasSerializedDataTypeConstantValidator.java b/api/src/main/java/org/fuin/esc/api/HasSerializedDataTypeConstantValidator.java
index cb12403d..c050aa18 100644
--- a/api/src/main/java/org/fuin/esc/api/HasSerializedDataTypeConstantValidator.java
+++ b/api/src/main/java/org/fuin/esc/api/HasSerializedDataTypeConstantValidator.java
@@ -75,7 +75,7 @@ public static SerializedDataType extractValue(final Class<?> clasz, final String
         if (result.message() == null) {
             return (SerializedDataType) result.value();
         }
-        throw new IllegalArgumentException(result.message());
+        throw new IllegalArgumentException(result.message() + " (" + clasz + ")");
     }
 
 }
diff --git a/api/src/main/java/org/fuin/esc/api/JandexSerializedDataTypeRegistry.java b/api/src/main/java/org/fuin/esc/api/JandexSerializedDataTypeRegistry.java
new file mode 100644
index 00000000..71494e95
--- /dev/null
+++ b/api/src/main/java/org/fuin/esc/api/JandexSerializedDataTypeRegistry.java
@@ -0,0 +1,101 @@
+package org.fuin.esc.api;
+
+import jakarta.validation.constraints.NotNull;
+import org.fuin.utils4j.JandexIndexFileReader;
+import org.fuin.utils4j.JandexUtils;
+import org.jboss.jandex.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.lang.reflect.Modifier;
+import java.util.*;
+
+/**
+ * Registry that is built up by scanning for classes that are annotated with {@link HasSerializedDataTypeConstant}.
+ * Inner classes are ignored.
+ */
+public class JandexSerializedDataTypeRegistry implements SerializedDataTypeRegistry {
+
+    private static final Logger LOG = LoggerFactory.getLogger(JandexSerializedDataTypeRegistry.class);
+
+    private final SimpleSerializedDataTypeRegistry delegate;
+
+    private final List<File> classesDirs;
+
+    private final List<Class<?>> classes;
+
+    /**
+     * Default constructor.
+     */
+    public JandexSerializedDataTypeRegistry() {
+        this(new File("target/classes"));
+    }
+
+    /**
+     * Constructor with classes directories. Most likely only used in tests.
+     *
+     * @param classesDirs Directories with class files.
+     */
+    public JandexSerializedDataTypeRegistry(final File... classesDirs) {
+        delegate = new SimpleSerializedDataTypeRegistry();
+        this.classesDirs = Arrays.asList(classesDirs);
+        classes = scanForClasses();
+        for (final Class<?> domainEventClass : classes) {
+            delegate.add(serializedDataTypeConstant(domainEventClass), domainEventClass);
+        }
+    }
+
+    @Override
+    @NotNull
+    public Class<?> findClass(@NotNull SerializedDataType type) {
+        return delegate.findClass(type);
+    }
+
+    /**
+     * Returns a list of known classes that can be serialized.
+     *
+     * @return SerializedDataType classes.
+     */
+    public List<Class<?>> getClasses() {
+        return Collections.unmodifiableList(classes);
+    }
+
+    private List<Class<?>> scanForClasses() {
+        final List<IndexView> indexes = new ArrayList<>();
+        indexes.add(new JandexIndexFileReader.Builder().addDefaultResource().build().loadR());
+        indexes.add(indexClassesDirs());
+        return findClasses(CompositeIndex.create(indexes));
+    }
+
+    private IndexView indexClassesDirs() {
+        final Indexer indexer = new Indexer();
+        final List<File> knownClassFiles = new ArrayList<>();
+        for (final File classesDir : classesDirs) {
+            JandexUtils.indexDir(indexer, knownClassFiles, classesDir);
+        }
+        return indexer.complete();
+    }
+
+    private static List<Class<?>> findClasses(final IndexView index) {
+        List<Class<?>> classes = new ArrayList<>();
+        final Collection<AnnotationInstance> annotationInstances = index.getAnnotations(DotName.createSimple(HasSerializedDataTypeConstant.class));
+        for (final AnnotationInstance annotationInstance : annotationInstances) {
+            final ClassInfo classInfo = annotationInstance.target().asClass();
+            if (!Modifier.isAbstract(classInfo.flags())
+                    && !Modifier.isInterface(classInfo.flags())
+                    && !classInfo.name().toString().contains("$")) {
+                final Class<?> clasz = JandexUtils.loadClass(classInfo.name());
+                classes.add(clasz);
+                LOG.info("Added SerializedDataType to {}: {}", JandexSerializedDataTypeRegistry.class.getSimpleName(), clasz.getName());
+            }
+        }
+        return classes;
+    }
+
+    public SerializedDataType serializedDataTypeConstant(Class<?> domainEventClass) {
+        final HasSerializedDataTypeConstant annotation = domainEventClass.getAnnotation(HasSerializedDataTypeConstant.class);
+        return HasSerializedDataTypeConstantValidator.extractValue(domainEventClass, annotation.value());
+    }
+
+}
diff --git a/api/src/test/java/org/fuin/esc/api/JandexSerializedDataTypeRegistryTest.java b/api/src/test/java/org/fuin/esc/api/JandexSerializedDataTypeRegistryTest.java
new file mode 100644
index 00000000..1083f1e8
--- /dev/null
+++ b/api/src/test/java/org/fuin/esc/api/JandexSerializedDataTypeRegistryTest.java
@@ -0,0 +1,26 @@
+package org.fuin.esc.api;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Test for the {@link JandexSerializedDataTypeRegistry} class.
+ */
+public class JandexSerializedDataTypeRegistryTest {
+
+    @Test
+    public void testCreate() {
+        final JandexSerializedDataTypeRegistry testee = new JandexSerializedDataTypeRegistry(new File("target/test-classes"));
+        assertThat(testee.getClasses()).containsOnly(MyEvent.class);
+    }
+
+    @Test
+    public void testFind() {
+        final JandexSerializedDataTypeRegistry testee = new JandexSerializedDataTypeRegistry(new File("target/test-classes"));
+        assertThat(testee.findClass(MyEvent.SER_TYPE)).isEqualTo(MyEvent.class);
+    }
+
+}
diff --git a/api/src/test/java/org/fuin/esc/api/MyEvent.java b/api/src/test/java/org/fuin/esc/api/MyEvent.java
index e59579b7..21dc7b9c 100644
--- a/api/src/test/java/org/fuin/esc/api/MyEvent.java
+++ b/api/src/test/java/org/fuin/esc/api/MyEvent.java
@@ -4,8 +4,11 @@
 /**
  * Example event.
  */
+@HasSerializedDataTypeConstant
 public class MyEvent {
 
+    public static final SerializedDataType SER_TYPE = new SerializedDataType("MyEvent");
+
     private String name;
 
     public MyEvent(final String name) {
diff --git a/api/src/test/resources/logback-test.xml b/api/src/test/resources/logback-test.xml
new file mode 100644
index 00000000..6062cc03
--- /dev/null
+++ b/api/src/test/resources/logback-test.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+
+	<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
+		<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
+			<Pattern>%d{yyyy.dd.MM HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
+		</encoder>
+	</appender>
+
+	<root level="info">
+		<appender-ref ref="CONSOLE" />
+	</root>
+
+	<!--
+	<logger name="org.fuin.esc" level="DEBUG"/>
+	-->
+
+</configuration>
diff --git a/pom.xml b/pom.xml
index 619c7cf8..63c9649e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -325,6 +325,12 @@
 				<version>4.0.1</version>
 			</dependency>
 
+			<dependency>
+				<groupId>io.smallrye</groupId>
+				<artifactId>jandex</artifactId>
+				<version>3.1.2</version>
+			</dependency>
+
 		</dependencies>
 
 	</dependencyManagement>
diff --git a/spi/src/main/java/org/fuin/esc/spi/Base64Data.java b/spi/src/main/java/org/fuin/esc/spi/Base64Data.java
index 2e8ca4d2..3c0679f0 100644
--- a/spi/src/main/java/org/fuin/esc/spi/Base64Data.java
+++ b/spi/src/main/java/org/fuin/esc/spi/Base64Data.java
@@ -32,6 +32,7 @@
 /**
  * Contains some Base64 encoded data.
  */
+@HasSerializedDataTypeConstant
 @XmlRootElement(name = Base64Data.EL_ROOT_NAME)
 public final class Base64Data implements ToJsonCapable {
 
diff --git a/spi/src/main/java/org/fuin/esc/spi/EscEvent.java b/spi/src/main/java/org/fuin/esc/spi/EscEvent.java
index 6f99e5ea..18cedf2f 100644
--- a/spi/src/main/java/org/fuin/esc/spi/EscEvent.java
+++ b/spi/src/main/java/org/fuin/esc/spi/EscEvent.java
@@ -39,6 +39,7 @@
 /**
  * An event structure.
  */
+@HasSerializedDataTypeConstant
 @XmlRootElement(name = EscEvent.EL_ROOT_NAME)
 public final class EscEvent implements ToJsonCapable {
 
diff --git a/spi/src/main/java/org/fuin/esc/spi/EscEvents.java b/spi/src/main/java/org/fuin/esc/spi/EscEvents.java
index f73a9385..6db7917c 100644
--- a/spi/src/main/java/org/fuin/esc/spi/EscEvents.java
+++ b/spi/src/main/java/org/fuin/esc/spi/EscEvents.java
@@ -40,6 +40,7 @@
 /**
  * A list of events.
  */
+@HasSerializedDataTypeConstant
 @XmlRootElement(name = EscEvents.EL_ROOT_NAME)
 public final class EscEvents implements ToJsonCapable {
 
diff --git a/spi/src/main/java/org/fuin/esc/spi/EscMeta.java b/spi/src/main/java/org/fuin/esc/spi/EscMeta.java
index f60d5e86..fc3ba014 100644
--- a/spi/src/main/java/org/fuin/esc/spi/EscMeta.java
+++ b/spi/src/main/java/org/fuin/esc/spi/EscMeta.java
@@ -40,6 +40,7 @@
 /**
  * A structure that contains the user's meta data and the system's meta information.
  */
+@HasSerializedDataTypeConstant
 @XmlRootElement(name = EscMeta.EL_ROOT_NAME)
 public final class EscMeta implements ToJsonCapable {
 
diff --git a/spi/src/test/java/org/fuin/esc/spi/JandexSerializedDataTypeRegistryTest.java b/spi/src/test/java/org/fuin/esc/spi/JandexSerializedDataTypeRegistryTest.java
new file mode 100644
index 00000000..2a269603
--- /dev/null
+++ b/spi/src/test/java/org/fuin/esc/spi/JandexSerializedDataTypeRegistryTest.java
@@ -0,0 +1,26 @@
+package org.fuin.esc.spi;
+
+import org.fuin.esc.api.JandexSerializedDataTypeRegistry;
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Test for the {@link JandexSerializedDataTypeRegistry} class.
+ */
+public class JandexSerializedDataTypeRegistryTest {
+
+    @Test
+    public void testBaseDataTypes() {
+        final JandexSerializedDataTypeRegistry testee = new JandexSerializedDataTypeRegistry();
+        assertThat(testee.getClasses()).containsOnly(
+                Base64Data.class,
+                EscEvent.class,
+                EscEvents.class,
+                EscMeta.class
+        );
+    }
+
+}