diff --git a/src/main/java/de/maishai/ast/Expression.java b/src/main/java/de/maishai/ast/Expression.java
index 7e11bae..a113f28 100644
--- a/src/main/java/de/maishai/ast/Expression.java
+++ b/src/main/java/de/maishai/ast/Expression.java
@@ -1,6 +1,14 @@
 package de.maishai.ast;
 
 
+import de.maishai.ast.records.Assignment;
+import de.maishai.ast.records.Binary;
+import de.maishai.ast.records.BoolConstant;
+import de.maishai.ast.records.CharConstant;
+import de.maishai.ast.records.Id;
+import de.maishai.ast.records.IntConstant;
+import de.maishai.ast.records.MethodCall;
+import de.maishai.ast.records.New;
 
-public interface Expression extends Node {
+public sealed interface Expression extends Node permits Assignment, Binary, BoolConstant, CharConstant, Id, IntConstant, MethodCall, New {
 }
diff --git a/src/main/java/de/maishai/ast/Node.java b/src/main/java/de/maishai/ast/Node.java
index b07e221..0c68bd6 100644
--- a/src/main/java/de/maishai/ast/Node.java
+++ b/src/main/java/de/maishai/ast/Node.java
@@ -1,4 +1,12 @@
 package de.maishai.ast;
 
-public interface Node {
+import de.maishai.ast.records.Block;
+import de.maishai.ast.records.Class;
+import de.maishai.ast.records.MainMethod;
+import de.maishai.ast.records.Method;
+import de.maishai.ast.records.Parameter;
+import de.maishai.ast.records.Program;
+import de.maishai.ast.records.Variable;
+
+public sealed interface Node permits Expression, Statement, Block, Class, MainMethod, Method, Parameter, Program, Variable {
 }
diff --git a/src/main/java/de/maishai/ast/Statement.java b/src/main/java/de/maishai/ast/Statement.java
index c9e690c..191bea6 100644
--- a/src/main/java/de/maishai/ast/Statement.java
+++ b/src/main/java/de/maishai/ast/Statement.java
@@ -1,3 +1,15 @@
 package de.maishai.ast;
-public interface Statement extends Node  {
+
+import de.maishai.ast.records.Break;
+import de.maishai.ast.records.Continue;
+import de.maishai.ast.records.DoWhile;
+import de.maishai.ast.records.For;
+import de.maishai.ast.records.IfElse;
+import de.maishai.ast.records.MethodCall;
+import de.maishai.ast.records.New;
+import de.maishai.ast.records.Return;
+import de.maishai.ast.records.ReturnVoid;
+import de.maishai.ast.records.While;
+
+public sealed interface Statement extends Node permits Break, Continue, DoWhile, For, IfElse, MethodCall, New, Return, ReturnVoid, While {
 }