diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 7d6e2f53..f41cb98a 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -78,7 +78,7 @@ repos:
   # More information can be found in its documentation:
   # https://docs.astral.sh/ruff/
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.15.7
+    rev: v0.15.9
     hooks:
     - id: ruff-check
       name: ruff
@@ -106,7 +106,7 @@ repos:
   # The project's documentation can be found at:
   # https://mypy.readthedocs.io/en/stable/index.html
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.19.1
+    rev: v1.20.0
     hooks:
     - id: mypy
       exclude: ^tests/.*$
diff --git a/oteapi_dlite/strategies/convert.py b/oteapi_dlite/strategies/convert.py
index dbd8cfa6..45642491 100644
--- a/oteapi_dlite/strategies/convert.py
+++ b/oteapi_dlite/strategies/convert.py
@@ -164,7 +164,7 @@ def get(self) -> DLiteResult:
         config = self.function_config.configuration
         module = importlib.import_module(config.module_name, config.package)
         function = getattr(module, config.function_name)
-        kwargs = config.kwargs
+        kwargs = config.kwargs or {}
 
         coll = get_collection(config.collection_id)