diff --git a/stages/diagram-recognition/src/main/kotlin/edu/kit/kastel/mcse/ardoco/erid/diagramrecognition/DiagramRecognitionMock.kt b/stages/diagram-recognition/src/main/kotlin/edu/kit/kastel/mcse/ardoco/erid/diagramrecognition/DiagramRecognitionMock.kt
index e26d4605e..8d04c73cc 100644
--- a/stages/diagram-recognition/src/main/kotlin/edu/kit/kastel/mcse/ardoco/erid/diagramrecognition/DiagramRecognitionMock.kt
+++ b/stages/diagram-recognition/src/main/kotlin/edu/kit/kastel/mcse/ardoco/erid/diagramrecognition/DiagramRecognitionMock.kt
@@ -17,7 +17,7 @@ import java.util.SortedMap
  */
 class DiagramRecognitionMock(
     private val goldStandardProject: GoldStandardDiagrams?,
-    additionalConfigs: SortedMap<String, String>,
+    additionalConfigs: SortedMap<String, String>?,
     dataRepository: DataRepository?
 ) :
     ExecutionStage(