diff --git a/src/caoscrawler/default_transformers.yml b/src/caoscrawler/default_transformers.yml
index 1821d9dd1c3cc3d8b982cd0e5f5eb3cfa07b3150..d0ad23912176bdfbf2446aa6e04bd7fa6b858777 100644
--- a/src/caoscrawler/default_transformers.yml
+++ b/src/caoscrawler/default_transformers.yml
@@ -8,4 +8,4 @@ split:
   function: split
 replace:
   package: caoscrawler.transformer_functions
-  function: split
+  function: replace
diff --git a/unittests/test_converters.py b/unittests/test_converters.py
index 67c93c74e4011bc402817b79a660a8c06ba38800..52ece13dc2269a3e3b16e6378166e91b084f4a7c 100644
--- a/unittests/test_converters.py
+++ b/unittests/test_converters.py
@@ -45,8 +45,8 @@ from caoscrawler.converters import (Converter, ConverterValidationError,
                                     handle_value, replace_variables)
 from caoscrawler.crawl import Crawler
 from caoscrawler.scanner import (_load_definition_from_yaml_dict,
-                                 create_converter_registry, load_definition,
-                                 create_transformer_registry)
+                                 create_converter_registry,
+                                 create_transformer_registry, load_definition)
 from caoscrawler.stores import GeneralStore
 from caoscrawler.structure_elements import (BooleanElement, DictElement,
                                             Directory, File, FloatElement,
@@ -401,39 +401,6 @@ def test_apply_transformers(converter_registry):
     assert values['a'] == ["a", "b", "c"]
 
 
-def test_apply_replace(converter_registry):
-    cfood_def = {"type": 'ListElement', "match_name": ".*",
-                 'transform': {'test': {'in': '$a', 'out': '$b', 'functions': [{
-                     'replace': {'insert': ':', "remove": "_"}}]}}}
-    values = GeneralStore()
-    values["a"] = "16_45"
-
-    # transformer_functions  = create_transformer_registry(crawler_definition)
-    transformer_functions = {"replace": replace}
-
-    conv = ListElementConverter(definition=cfood_def, name='test',
-                                converter_registry=converter_registry)
-
-    conv.apply_transformers(values, transformer_functions)
-    assert values['b'] == "16:45"
-
-def test_apply_replace_from_def(converter_registry):
-    cfood_def = {"type": 'ListElement', "match_name": ".*",
-                 'transform': {'test': {'in': '$a', 'out': '$b', 'functions': [{
-                     'replace': {'insert': ':', "remove": "_"}}]}}}
-    values = GeneralStore()
-    values["a"] = "16_45"
-
-    transformer_functions  = create_transformer_registry({})
-    # transformer_functions = {"replace": replace}
-
-    conv = ListElementConverter(definition=cfood_def, name='test',
-                                converter_registry=converter_registry)
-
-    conv.apply_transformers(values, transformer_functions)
-    assert values['b'] == "16:45"
-
-
 def test_filter_children_of_directory(converter_registry, capsys):
     """Verify that children (i.e., files) in a directory are filtered or sorted correctly. """
     test_dir = Directory("examples_filter_children", UNITTESTDIR /
diff --git a/unittests/test_transformers.py b/unittests/test_transformers.py
index ac530c9147fd7a4c86fa2ef668b6366a722935b0..02d932d13cc3fad52048b08e2b9fe56f11db2ae7 100644
--- a/unittests/test_transformers.py
+++ b/unittests/test_transformers.py
@@ -28,6 +28,7 @@ Currently, this is under development.
 See: https://gitlab.indiscale.com/caosdb/src/caosdb-crawler/-/issues/107
 """
 
+import importlib
 from functools import partial
 from pathlib import Path
 from tempfile import NamedTemporaryFile
@@ -36,10 +37,10 @@ from unittest.mock import MagicMock, Mock, patch
 import caosdb as db
 import pytest
 import yaml
-from caoscrawler.scanner import (create_converter_registry, load_definition,
-                                 scan_directory, scan_structure_elements)
-from caoscrawler.structure_elements import (DictElement, DictListElement,
-                                            DictTextElement, File)
+from caoscrawler.converters import Converter, ListElementConverter
+from caoscrawler.scanner import create_transformer_registry, scan_directory
+from caoscrawler.stores import GeneralStore
+from caoscrawler.transformer_functions import replace, split
 from pytest import raises
 
 UNITTESTDIR = Path(__file__).parent
@@ -79,3 +80,69 @@ def test_simple_transformer():
         else:
             # unkown error, something wrong with test directories
             assert False
+
+
+@pytest.fixture
+def converter_registry():
+    converter_registry: dict[str, dict[str, str]] = {
+        "Directory": {
+            "converter": "DirectoryConverter",
+            "package": "caoscrawler.converters"},
+        "MarkdownFile": {
+            "converter": "MarkdownFileConverter",
+            "package": "caoscrawler.converters"},
+        "Date": {
+            "converter": "DateElementConverter",
+            "package": "caoscrawler.converters"},
+        "DictElement": {
+            "converter": "DictElementConverter",
+            "package": "caoscrawler.converters"},
+        "TextElement": {
+            "converter": "TextElementConverter",
+            "package": "caoscrawler.converters"},
+        "ListElement": {
+            "converter": "ListElementConverter",
+            "package": "caoscrawler.converters"},
+        "JSONFile": {
+            "converter": "JSONFileConverter",
+            "package": "caoscrawler.converters"},
+    }
+
+    for key, value in converter_registry.items():
+        module = importlib.import_module(value["package"])
+        value["class"] = getattr(module, value["converter"])
+    return converter_registry
+
+
+def test_apply_replace(converter_registry):
+    cfood_def = {"type": 'ListElement', "match_name": ".*",
+                 'transform': {'test': {'in': '$a', 'out': '$b', 'functions': [{
+                     'replace': {'insert': ':', "remove": "_"}}]}}}
+    values = GeneralStore()
+    values["a"] = "16_45"
+
+    # transformer_functions  = create_transformer_registry(crawler_definition)
+    transformer_functions = {"replace": replace}
+
+    conv = ListElementConverter(definition=cfood_def, name='test',
+                                converter_registry=converter_registry)
+
+    conv.apply_transformers(values, transformer_functions)
+    assert values['b'] == "16:45"
+
+
+def test_apply_replace_from_def(converter_registry):
+    cfood_def = {"type": 'ListElement', "match_name": ".*",
+                 'transform': {'test': {'in': '$a', 'out': '$b', 'functions': [{
+                     'replace': {'insert': ':', "remove": "_"}}]}}}
+    values = GeneralStore()
+    values["a"] = "16_45"
+
+    transformer_functions = create_transformer_registry({})
+    # transformer_functions = {"replace": replace}
+
+    conv = ListElementConverter(definition=cfood_def, name='test',
+                                converter_registry=converter_registry)
+
+    conv.apply_transformers(values, transformer_functions)
+    assert values['b'] == "16:45"