diff --git a/rsconcept/backend/apps/library/serializers/data_access.py b/rsconcept/backend/apps/library/serializers/data_access.py
index a363f8ea..b010b09a 100644
--- a/rsconcept/backend/apps/library/serializers/data_access.py
+++ b/rsconcept/backend/apps/library/serializers/data_access.py
@@ -84,10 +84,10 @@ class LibraryItemDetailsSerializer(serializers.ModelSerializer):
         read_only_fields = ('owner', 'id', 'item_type')
 
     def get_editors(self, instance: LibraryItem) -> list[int]:
-        return list(instance.editors().values_list('pk', flat=True))
+        return list(instance.editors().order_by('pk').values_list('pk', flat=True))
 
     def get_versions(self, instance: LibraryItem) -> list:
-        return [VersionInnerSerializer(item).data for item in instance.versions()]
+        return [VersionInnerSerializer(item).data for item in instance.versions().order_by('pk')]
 
 
 class UserTargetSerializer(serializers.Serializer):
diff --git a/rsconcept/backend/apps/oss/serializers/data_access.py b/rsconcept/backend/apps/oss/serializers/data_access.py
index 79d0e4be..0a02d18a 100644
--- a/rsconcept/backend/apps/oss/serializers/data_access.py
+++ b/rsconcept/backend/apps/oss/serializers/data_access.py
@@ -207,10 +207,10 @@ class OperationSchemaSerializer(serializers.ModelSerializer):
         result = LibraryItemDetailsSerializer(instance).data
         oss = OperationSchema(instance)
         result['items'] = []
-        for operation in oss.operations():
+        for operation in oss.operations().order_by('pk'):
             result['items'].append(OperationSerializer(operation).data)
         result['arguments'] = []
-        for argument in oss.arguments():
+        for argument in oss.arguments().order_by('pk'):
             result['arguments'].append(ArgumentSerializer(argument).data)
         result['substitutions'] = []
         for substitution in oss.substitutions().values(
@@ -221,6 +221,6 @@ class OperationSchemaSerializer(serializers.ModelSerializer):
             original_term=F('original__term_resolved'),
             substitution_alias=F('substitution__alias'),
             substitution_term=F('substitution__term_resolved'),
-        ):
+        ).order_by('pk'):
             result['substitutions'].append(substitution)
         return result