diff --git a/lib/src/main/java/de/sipgate/federmappe/DefaultSerializersModule.kt b/lib/src/main/java/de/sipgate/federmappe/DefaultSerializersModule.kt
new file mode 100644
index 0000000..c0a47dd
--- /dev/null
+++ b/lib/src/main/java/de/sipgate/federmappe/DefaultSerializersModule.kt
@@ -0,0 +1,11 @@
+package de.sipgate.federmappe
+
+import de.sipgate.federmappe.serializers.DateSerializer
+import de.sipgate.federmappe.serializers.UriSerializer
+import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.contextual
+
+val DefaultSerializersModule = SerializersModule {
+    contextual(DateSerializer)
+    contextual(UriSerializer)
+}
diff --git a/lib/src/main/java/de/sipgate/federmappe/DocumentSnapshotExt.kt b/lib/src/main/java/de/sipgate/federmappe/DocumentSnapshotExt.kt
index 10a3cb8..be3da6e 100644
--- a/lib/src/main/java/de/sipgate/federmappe/DocumentSnapshotExt.kt
+++ b/lib/src/main/java/de/sipgate/federmappe/DocumentSnapshotExt.kt
@@ -1,10 +1,13 @@
 package de.sipgate.federmappe
 
 import com.google.firebase.firestore.DocumentSnapshot
+import kotlinx.serialization.modules.SerializersModule
 
-inline fun <reified T : Any> DocumentSnapshot.toObject(errorHandler: (Throwable) -> T? = { throw it }): T? =
+inline fun <reified T : Any> DocumentSnapshot.toObject(
+    customSerializers: SerializersModule = DefaultSerializersModule,
+    errorHandler: (Throwable) -> T? = { throw it }): T? =
     try {
-        data?.toObjectWithSerializer<T>()
+        data?.toObjectWithSerializer<T>(customSerializers = customSerializers)
     } catch (ex: Throwable) {
         errorHandler(ex)
     }
diff --git a/lib/src/main/java/de/sipgate/federmappe/QuerySnapshotExt.kt b/lib/src/main/java/de/sipgate/federmappe/QuerySnapshotExt.kt
index 782f79c..c2d76e1 100644
--- a/lib/src/main/java/de/sipgate/federmappe/QuerySnapshotExt.kt
+++ b/lib/src/main/java/de/sipgate/federmappe/QuerySnapshotExt.kt
@@ -1,11 +1,14 @@
 package de.sipgate.federmappe
 
 import com.google.firebase.firestore.QuerySnapshot
+import kotlinx.serialization.modules.SerializersModule
 
-inline fun <reified T : Any> QuerySnapshot.toObject(errorHandler: (Throwable) -> T? = { throw it }): List<T?> =
+inline fun <reified T : Any> QuerySnapshot.toObject(
+    customSerializers: SerializersModule = DefaultSerializersModule,
+    errorHandler: (Throwable) -> T? = { throw it }): List<T?> =
     map {
         try {
-            it.data.toObjectWithSerializer()
+            it.data.toObjectWithSerializer(customSerializers = customSerializers)
         } catch (ex: Throwable) {
             errorHandler(ex)
         }
diff --git a/lib/src/main/java/de/sipgate/federmappe/StringMapExt.kt b/lib/src/main/java/de/sipgate/federmappe/StringMapExt.kt
index a14639b..41a032c 100644
--- a/lib/src/main/java/de/sipgate/federmappe/StringMapExt.kt
+++ b/lib/src/main/java/de/sipgate/federmappe/StringMapExt.kt
@@ -1,18 +1,12 @@
 package de.sipgate.federmappe
 
-import de.sipgate.federmappe.serializers.DateSerializer
-import de.sipgate.federmappe.serializers.UriSerializer
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.modules.SerializersModule
-import kotlinx.serialization.modules.contextual
 import kotlinx.serialization.serializer
 
 inline fun <reified T : Any> Map<String, Any>.toObjectWithSerializer(
     serializer: KSerializer<T> = serializer<T>(),
-    customSerializers: SerializersModule = SerializersModule {
-        contextual(DateSerializer)
-        contextual(UriSerializer)
-    }
+    customSerializers: SerializersModule
 ): T = serializer.deserialize(
     StringMapToObjectDecoder(
         this,