diff --git a/build.xml b/build.xml
index 2780510..d08656a 100644
--- a/build.xml
+++ b/build.xml
@@ -19,6 +19,7 @@
     </target>
     <target name="run" description="execution" depends="compile">
         <java classname="lsystem.Main" fork="true">
+            <jvmarg value="-ea"/>
             <classpath refid="project.classpath"/>
         </java>
     </target>
diff --git a/src/lsystem/engine/Parser.java b/src/lsystem/engine/Parser.java
index f4971e2..a21eded 100644
--- a/src/lsystem/engine/Parser.java
+++ b/src/lsystem/engine/Parser.java
@@ -97,7 +97,7 @@ public class Parser {
         Element root = null;
         Element workingElement = null;
         String number = "";
-        boolean bracket = false;
+        List<Element> bracket = new ArrayList<>();
         float[] appliedRotation = new float[3];
         Element lastCreatedElement = null;
 
@@ -120,6 +120,7 @@ public class Parser {
                         lastCreatedElement = element;
                         appliedRotation = new float[]{0f, 0f, 0f};
                         workingElement.children.add(element);
+                        workingElement = lastCreatedElement;
                     }
                 } else {
                     float n = getFloat(number);
@@ -135,11 +136,11 @@ public class Parser {
                 }
                 if(c == '[') {
                     workingElement = lastCreatedElement;
-                    bracket = true;
+                    bracket.add(lastCreatedElement);
                 }
                 if(c == ']') {
-                    assert workingElement != null;
-                    workingElement = workingElement.parent;
+                    assert workingElement != null && !bracket.isEmpty();
+                    workingElement = bracket.remove(bracket.size() - 1);
                 }
             }
         }