diff --git a/datagen-plugin/pom.xml b/datagen-plugin/pom.xml
index bf80e21..f8d5985 100644
--- a/datagen-plugin/pom.xml
+++ b/datagen-plugin/pom.xml
@@ -16,7 +16,7 @@
 	<properties>
 		<revision>1.0.0.0-SNAPSHOT</revision>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<fastutil.version>8.5.11</fastutil.version>
+		<fastutil.version>8.5.12</fastutil.version>
 		<maven.version>4.0.0-alpha-3</maven.version>
 	</properties>
 	<repositories>
@@ -59,7 +59,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-plugin-plugin</artifactId>
-				<version>3.7.1</version>
+				<version>3.10.1</version>
 				<dependencies>
 					<dependency>
 						<groupId>org.apache.maven.plugin-tools</groupId>
@@ -84,7 +84,7 @@
 				<artifactId>maven-compiler-plugin</artifactId>
 				<version>3.10.1</version>
 				<configuration>
-					<release>17</release>
+					<release>21</release>
 					<encoding>UTF-8</encoding>
 				</configuration>
 			</plugin>
@@ -185,7 +185,7 @@
 		<dependency>
 			<groupId>org.yaml</groupId>
 			<artifactId>snakeyaml</artifactId>
-			<version>1.33</version>
+			<version>2.0</version>
 		</dependency>
 		<dependency>
 			<groupId>net.fabricmc</groupId>
@@ -195,7 +195,7 @@
 		<dependency>
 			<groupId>org.jetbrains</groupId>
 			<artifactId>annotations</artifactId>
-			<version>23.1.0</version>
+			<version>24.0.1</version>
 		</dependency>
 		<dependency>
 			<groupId>it.unimi.dsi</groupId>
@@ -217,7 +217,7 @@
 		<dependency>
 			<groupId>org.apache.maven.plugin-tools</groupId>
 			<artifactId>maven-plugin-annotations</artifactId>
-			<version>3.7.1</version>
+			<version>3.8.1</version>
 			<scope>provided</scope>
 		</dependency>
 		<dependency>
@@ -233,7 +233,7 @@
 		<dependency>
 			<groupId>org.apache.logging.log4j</groupId>
 			<artifactId>log4j-core</artifactId>
-      <version>2.19.0</version>
+      <version>2.20.0</version>
     </dependency>
 		<dependency>
 			<groupId>org.apache.commons</groupId>
@@ -243,7 +243,7 @@
 		<dependency>
 			<groupId>org.apache.logging.log4j</groupId>
 			<artifactId>log4j-slf4j2-impl</artifactId>
-			<version>2.19.0</version>
+			<version>2.20.0</version>
 			<exclusions>
 				<exclusion>
 					<groupId>junit</groupId>
diff --git a/datagen-plugin/src/main/java/it/cavallium/datagen/plugin/classgen/GenDataSuperX.java b/datagen-plugin/src/main/java/it/cavallium/datagen/plugin/classgen/GenDataSuperX.java
index 2f7b304..e27779f 100644
--- a/datagen-plugin/src/main/java/it/cavallium/datagen/plugin/classgen/GenDataSuperX.java
+++ b/datagen-plugin/src/main/java/it/cavallium/datagen/plugin/classgen/GenDataSuperX.java
@@ -3,6 +3,7 @@ package it.cavallium.datagen.plugin.classgen;
 import com.squareup.javapoet.ClassName;
 import com.squareup.javapoet.MethodSpec;
 import com.squareup.javapoet.ParameterSpec;
+import com.squareup.javapoet.TypeName;
 import com.squareup.javapoet.TypeSpec;
 import it.cavallium.datagen.plugin.ClassGenerator;
 import it.cavallium.datagen.plugin.ComputedTypeSuper;
@@ -36,6 +37,17 @@ public class GenDataSuperX extends ClassGenerator {
 
 		classBuilder.addModifiers(Modifier.PUBLIC);
 
+		if (version.isCurrent()) {
+			classBuilder.addModifiers(Modifier.SEALED);
+			Stream<TypeName> superTypesThatExtendThisSuperType = dataModel.getSuperTypesComputed(version)
+					.filter(computedTypeSuper -> dataModel.getExtendsInterfaces(computedTypeSuper).anyMatch(typeSuper::equals))
+					.map(computedTypeSuper -> computedTypeSuper.getJTypeName(basePackageName));
+			Stream<TypeName> subTypes = typeSuper.subTypes().stream()
+					.map(subType -> subType.getJTypeName(basePackageName));
+			Stream<TypeName> permittedSubclasses = Stream.concat(superTypesThatExtendThisSuperType, subTypes).distinct();
+			classBuilder.addPermittedSubclasses(permittedSubclasses.toList());
+		}
+
 		dataModel.getTypeSameVersions(typeSuper).forEach(v -> {
 			var iTypeClass = ClassName.get(v.getPackage(basePackageName), "IBaseType");
 			classBuilder.addSuperinterface(iTypeClass);
diff --git a/datagen/pom.xml b/datagen/pom.xml
index 086485d..73f1a44 100644
--- a/datagen/pom.xml
+++ b/datagen/pom.xml
@@ -67,7 +67,7 @@
 				<artifactId>maven-compiler-plugin</artifactId>
 				<version>3.8.1</version>
 				<configuration>
-					<release>17</release>
+					<release>21</release>
 					<encoding>UTF-8</encoding>
 				</configuration>
 			</plugin>
@@ -159,7 +159,7 @@
 										</goals>
 									</pluginExecutionFilter>
 									<action>
-										<ignore></ignore>
+										<ignore/>
 									</action>
 								</pluginExecution>
 							</pluginExecutions>