diff --git a/src/caoscrawler/converters.py b/src/caoscrawler/converters.py
index eb41325bd798126c4d06d92f6ea398eaa1ebbb72..b9070c121133fa8cb406d89f425f4d9674a0b2cf 100644
--- a/src/caoscrawler/converters.py
+++ b/src/caoscrawler/converters.py
@@ -23,7 +23,6 @@
 # ** end header
 #
 
-
 from __future__ import annotations
 
 import datetime
@@ -33,6 +32,7 @@ import os
 import re
 import warnings
 from abc import ABCMeta, abstractmethod
+from inspect import signature
 from string import Template
 from typing import Any, List, Optional, Tuple, Union
 
@@ -322,9 +322,10 @@ class Converter(object, metaclass=ABCMeta):
 
         Parameters
         ----------
-        definition: dict, stuffPlease refer to XX to learn about the structure that the definition dict must have
+        definition: dict, Please refer to ``src/doc/converters.rst`` to learn about the structure
+                    that the definition dict must have.
         converter_registry: dict, A dictionary that contains converter names as keys and dicts as
-        values. Those value dicts have the keys 'converter' and 'package'.
+                            values. Those value dicts have the keys 'converter' and 'package'.
         """
 
         self.definition = definition
@@ -444,7 +445,11 @@ class Converter(object, metaclass=ABCMeta):
                 # Retrieve the function from the dictionary:
                 tr_func = transformer_functions[tr_func_key]
                 # Call the function:
-                out_value = tr_func(in_value, tr_func_params)
+                sig = signature(tr_func)
+                if len(sig.parameters) == 1 and len(tr_func_params) == 0:
+                    out_value = tr_func(in_value)
+                else:
+                    out_value = tr_func(in_value, tr_func_params)
                 # The next in_value is the current out_value:
                 in_value = out_value
             # If everything succeeded, store the final value in the general store:
diff --git a/src/caoscrawler/scanner.py b/src/caoscrawler/scanner.py
index 25f72e56d460a2e0c8481ba7c5dc2818937ad4fa..18d722ed8c485dc0472344407f345a7a0e517b60 100644
--- a/src/caoscrawler/scanner.py
+++ b/src/caoscrawler/scanner.py
@@ -235,6 +235,8 @@ def initialize_converters(crawler_definition: dict, converter_registry: dict):
             continue
         elif key == "Converters":
             continue
+        elif key == "Transformers":
+            continue
         converters.append(Converter.converter_factory(
             value, key, converter_registry))
 
diff --git a/unittests/test_directories/test_transformers/cfood.yml b/unittests/test_directories/test_transformers/cfood.yml
index 9208d62c717e2435417f2bda54592dbaa57c332f..9064bfad9e2abbb9bf494bec03e4e82b7f6065a7 100644
--- a/unittests/test_directories/test_transformers/cfood.yml
+++ b/unittests/test_directories/test_transformers/cfood.yml
@@ -1,5 +1,10 @@
 
 # See: https://gitlab.indiscale.com/caosdb/src/caosdb-crawler/-/issues/107
+#
+Transformers:
+  ceil:
+    function: quote
+    package: shlex
 
 RootDir:
   type: Directory
@@ -30,3 +35,15 @@ RootDir:
           Day: $day_long
           DayShort: $day_short  # just for checking, whether this variable remains
           DaySplit: $day_split  # just for checking, whether this variable remains
+    Testfi:
+      type: File
+      match: ^(?P<no>(\d+ )*)$
+      transform:
+        up:
+          in: $no
+          out: $no
+          functions:
+          - ceil: {}
+      records:
+        Number:
+          num: $no
diff --git a/unittests/test_transformers.py b/unittests/test_transformers.py
index 47b31d0b0173786d58b2e7169342dea9fb11a03e..06b089f79f1c2eb75ad9ca0fa116290a253a0666 100644
--- a/unittests/test_transformers.py
+++ b/unittests/test_transformers.py
@@ -56,18 +56,24 @@ def test_simple_transformer():
                              "cfood.yml")
 
     for r in records:
-        assert r.get_property("Day") is not None
-        assert r.get_property("DayShort") is not None
-        assert r.get_property("DayShort").value != "$day_short"
-        if r.get_property("DayShort").value == "Unk":
-            # This unkown folder should not lead to a replacement
-            assert r.get_property("Day").value == "Unk"
-            assert r.get_property("DaySplit").value == ["Unk"]
-        elif r.get_property("DayShort").value == "Mon":
-            assert r.get_property("Day").value == "Monday"
-            assert r.get_property("DaySplit").value == ["M", "n"]
-        elif r.get_property("DayShort").value == "Tue":
-            assert r.get_property("Day").value == "Tuesday"
-            assert r.get_property("DaySplit").value == ["Tue"]
+        if r.parents[0].name == "DayFolder":
+            assert r.get_property("Day") is not None
+            assert r.get_property("DayShort") is not None
+            assert r.get_property("DayShort").value != "$day_short"
+            if r.get_property("DayShort").value == "Unk":
+                # This unkown folder should not lead to a replacement
+                assert r.get_property("Day").value == "Unk"
+                assert r.get_property("DaySplit").value == ["Unk"]
+            elif r.get_property("DayShort").value == "Mon":
+                assert r.get_property("Day").value == "Monday"
+                assert r.get_property("DaySplit").value == ["M", "n"]
+            elif r.get_property("DayShort").value == "Tue":
+                assert r.get_property("Day").value == "Tuesday"
+                assert r.get_property("DaySplit").value == ["Tue"]
+            else:
+                raise RuntimeError("There is no other short version!")
+        elif r.parents[0].name == "Number":
+            assert r.get_property("num") is not None
+            assert r.get_property("num").value == "'12345 5 '"
         else:
-            raise RuntimeError("There is no other short version!")
+            raise RuntimeError("unkown error")