diff --git a/dynawaltz/src/main/java/com/powsybl/dynawaltz/suppliers/curves/CurvesJsonDeserializer.java b/dynawaltz/src/main/java/com/powsybl/dynawaltz/suppliers/curves/CurvesJsonDeserializer.java
index 4c9a49aa1..9c76bb6a7 100644
--- a/dynawaltz/src/main/java/com/powsybl/dynawaltz/suppliers/curves/CurvesJsonDeserializer.java
+++ b/dynawaltz/src/main/java/com/powsybl/dynawaltz/suppliers/curves/CurvesJsonDeserializer.java
@@ -22,7 +22,7 @@
  */
 public class CurvesJsonDeserializer extends StdDeserializer<List<DynawoCurvesBuilder>> {
 
-    private final Supplier<DynawoCurvesBuilder> builderConstructor;
+    private transient final Supplier<DynawoCurvesBuilder> builderConstructor;
 
     public CurvesJsonDeserializer(Supplier<DynawoCurvesBuilder> builderConstructor) {
         super(List.class);
diff --git a/dynawaltz/src/test/java/com/powsybl/dynawaltz/builders/CurvesBuilderTest.java b/dynawaltz/src/test/java/com/powsybl/dynawaltz/builders/CurvesBuilderTest.java
index ffe9debad..189862a8e 100644
--- a/dynawaltz/src/test/java/com/powsybl/dynawaltz/builders/CurvesBuilderTest.java
+++ b/dynawaltz/src/test/java/com/powsybl/dynawaltz/builders/CurvesBuilderTest.java
@@ -19,7 +19,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class CurvesBuilderTest {
+class CurvesBuilderTest {
 
     private ReportNode reporter;