diff --git a/processor/_main.py b/processor/_main.py
index 1f5c76f..c591c24 100644
--- a/processor/_main.py
+++ b/processor/_main.py
@@ -6,7 +6,7 @@
 
 __all__ = ['set_data_dir', 'process']
 
-_data_dir = None
+_data_dir: Directory | None = None
 
 
 def set_data_dir(data_dir):
@@ -21,7 +21,9 @@ def process(option):
         raise ValueError('No data directory set.')
     if option['desinventar']['merge']:
         merge_controller.start_merging(_data_dir)
+        _data_dir.update()
     if option['desinventar']['slice']:
         slice_controller.start_slice(_data_dir)
+        _data_dir.update()
     if option['emdat']['process']:
         emdat_controller.start_emdat(_data_dir)
diff --git a/processor/_utils/_directory.py b/processor/_utils/_directory.py
index e3e2c35..09ce309 100644
--- a/processor/_utils/_directory.py
+++ b/processor/_utils/_directory.py
@@ -53,7 +53,7 @@ def __init__(self, path: str):
         self.__files: list[File] = []
         self.__directories: list[Directory] = []
         self.__content_names: list[str] = []
-        self.__update()
+        self.update()
 
     def __scan_directory(self):
         with os.scandir(self.__path) as it:
@@ -63,7 +63,7 @@ def __scan_directory(self):
                 elif entry.is_dir():
                     self.__directories.append(Directory(entry.path))
 
-    def __update(self):
+    def update(self):
         self.__files = []
         self.__directories = []
         self.__scan_directory()
@@ -153,7 +153,7 @@ def create_subdirectory(self, directory):
         if os.path.exists(path):
             return
         os.makedirs(path)
-        self.__update()
+        self.update()
 
     def get_contents(self):
         """Returns a list of the files and subdirectories in the directory."""