diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/Node.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/Node.kt
index ddc0e09218..a2322d695f 100644
--- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/Node.kt
+++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/Node.kt
@@ -32,16 +32,16 @@ import de.fraunhofer.aisec.cpg.TranslationContext
 import de.fraunhofer.aisec.cpg.TypeManager
 import de.fraunhofer.aisec.cpg.frontends.Handler
 import de.fraunhofer.aisec.cpg.frontends.Language
-import de.fraunhofer.aisec.cpg.graph.concepts.OverlaySingleEdge
-import de.fraunhofer.aisec.cpg.graph.declarations.*
-import de.fraunhofer.aisec.cpg.graph.edges.*
+import de.fraunhofer.aisec.cpg.graph.declarations.MethodDeclaration
+import de.fraunhofer.aisec.cpg.graph.declarations.RecordDeclaration
+import de.fraunhofer.aisec.cpg.graph.declarations.TranslationUnitDeclaration
 import de.fraunhofer.aisec.cpg.graph.edges.ast.astEdgesOf
-import de.fraunhofer.aisec.cpg.graph.edges.flows.ControlDependences
-import de.fraunhofer.aisec.cpg.graph.edges.flows.Dataflows
-import de.fraunhofer.aisec.cpg.graph.edges.flows.EvaluationOrders
-import de.fraunhofer.aisec.cpg.graph.edges.flows.FullDataflowGranularity
-import de.fraunhofer.aisec.cpg.graph.edges.flows.ProgramDependences
-import de.fraunhofer.aisec.cpg.graph.scopes.*
+import de.fraunhofer.aisec.cpg.graph.edges.flows.*
+import de.fraunhofer.aisec.cpg.graph.edges.overlay.OverlaySingleEdge
+import de.fraunhofer.aisec.cpg.graph.edges.unwrapping
+import de.fraunhofer.aisec.cpg.graph.scopes.GlobalScope
+import de.fraunhofer.aisec.cpg.graph.scopes.RecordScope
+import de.fraunhofer.aisec.cpg.graph.scopes.Scope
 import de.fraunhofer.aisec.cpg.helpers.SubgraphWalker
 import de.fraunhofer.aisec.cpg.helpers.neo4j.LocationConverter
 import de.fraunhofer.aisec.cpg.helpers.neo4j.NameConverter
@@ -53,7 +53,10 @@ import java.util.*
 import kotlin.uuid.Uuid
 import org.apache.commons.lang3.builder.ToStringBuilder
 import org.apache.commons.lang3.builder.ToStringStyle
-import org.neo4j.ogm.annotation.*
+import org.neo4j.ogm.annotation.GeneratedValue
+import org.neo4j.ogm.annotation.Id
+import org.neo4j.ogm.annotation.Relationship
+import org.neo4j.ogm.annotation.Transient
 import org.neo4j.ogm.annotation.typeconversion.Convert
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/OverlayNode.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/OverlayNode.kt
index 378c2e334a..c8cc0f888a 100644
--- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/OverlayNode.kt
+++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/OverlayNode.kt
@@ -45,4 +45,3 @@ abstract class OverlayNode() : Node() {
         )
     var underlyingNode by unwrapping(OverlayNode::underlyingNodeEdge)
 }
-
diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/concepts/Concept.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/concepts/Concept.kt
index a28fea3171..d589f035d5 100644
--- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/concepts/Concept.kt
+++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/concepts/Concept.kt
@@ -26,6 +26,7 @@
 package de.fraunhofer.aisec.cpg.graph.concepts
 
 import de.fraunhofer.aisec.cpg.graph.OverlayNode
+import org.neo4j.ogm.annotation.Relationship
 
 /**
  * Represents a new concept added to the CPG. This is intended for modelling "concepts" like
@@ -34,5 +35,5 @@ import de.fraunhofer.aisec.cpg.graph.OverlayNode
  */
 abstract class Concept<T : Operation>() : OverlayNode() {
     /** All [Operation]s belonging to this concept. */
-    val ops: Set<T> = setOf()
+    val ops: MutableSet<T> = mutableSetOf()
 }
diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/edges/overlay/Overlay.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/edges/overlay/Overlay.kt
index afe906da1c..aa2d607720 100644
--- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/edges/overlay/Overlay.kt
+++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/edges/overlay/Overlay.kt
@@ -1,3 +1,28 @@
+/*
+ * Copyright (c) 2024, Fraunhofer AISEC. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ *                    $$$$$$\  $$$$$$$\   $$$$$$\
+ *                   $$  __$$\ $$  __$$\ $$  __$$\
+ *                   $$ /  \__|$$ |  $$ |$$ /  \__|
+ *                   $$ |      $$$$$$$  |$$ |$$$$\
+ *                   $$ |      $$  ____/ $$ |\_$$ |
+ *                   $$ |  $$\ $$ |      $$ |  $$ |
+ *                   \$$$$$   |$$ |      \$$$$$   |
+ *                    \______/ \__|       \______/
+ *
+ */
 package de.fraunhofer.aisec.cpg.graph.edges.overlay
 
 import de.fraunhofer.aisec.cpg.graph.Node
@@ -6,7 +31,6 @@ import de.fraunhofer.aisec.cpg.graph.edges.collections.EdgeSingletonList
 import de.fraunhofer.aisec.cpg.graph.edges.collections.MirroredEdgeCollection
 import kotlin.reflect.KProperty
 
-
 class OverlayEdge(start: Node, end: Node) : Edge<Node>(start, end) {
     override var labels: Set<String> = setOf("OVERLAY")
 }
diff --git a/cpg-neo4j/src/test/kotlin/de/fraunhofer/aisec/cpg_vis_neo4j/Neo4JTest.kt b/cpg-neo4j/src/test/kotlin/de/fraunhofer/aisec/cpg_vis_neo4j/Neo4JTest.kt
index f6c6fc4b5d..a623d5c1bc 100644
--- a/cpg-neo4j/src/test/kotlin/de/fraunhofer/aisec/cpg_vis_neo4j/Neo4JTest.kt
+++ b/cpg-neo4j/src/test/kotlin/de/fraunhofer/aisec/cpg_vis_neo4j/Neo4JTest.kt
@@ -67,9 +67,9 @@ class Neo4JTest {
         val connectCall = result.calls["connect"]
 
         abstract class NetworkingOperation(
-            concept: Concept<*>,
+            concept: Concept<out Operation>,
         ) : Operation(concept)
-        class Connect(concept: Concept<*>) : NetworkingOperation(concept)
+        class Connect(concept: Concept<out Operation>) : NetworkingOperation(concept)
         class Networking() : Concept<NetworkingOperation>()
 
         val nw = Networking()
@@ -78,6 +78,7 @@ class Neo4JTest {
         val connect = Connect(concept = nw)
         connect.underlyingNode = connectCall
         connect.name = Name("connect")
+        nw.ops += connect
 
         assertEquals(connect, connectCall?.overlayNode)