diff --git a/api/advent22_api/core/config.py b/api/advent22_api/core/config.py
index 97b5461..39cebb0 100644
--- a/api/advent22_api/core/config.py
+++ b/api/advent22_api/core/config.py
@@ -1,13 +1,11 @@
-import re
 import tomllib
-from enum import Enum
-from random import Random
 
 from markdown import markdown
 from pydantic import BaseModel, ConfigDict, field_validator
 
 from .dav.webdav import WebDAV
 from .settings import SETTINGS
+from .transformed_string import TransformedString
 
 
 class User(BaseModel):
@@ -15,88 +13,6 @@ class User(BaseModel):
     password: str
 
 
-class TransformedString(BaseModel):
-    class __Whitespace(str, Enum):
-        # unverändert
-        KEEP = "KEEP"
-
-        # Leerzeichen an Anfang und Ende entfernen
-        STRIP = "STRIP"
-
-        # whitespace durch Leerzeichen ersetzen
-        SPACE = "SPACE"
-
-        # whitespace entfernen
-        REMOVE = "REMOVE"
-
-    class __SpecialChars(str, Enum):
-        # unverändert
-        KEEP = "KEEP"
-
-        # Sonderzeichen entfernen
-        REMOVE = "REMOVE"
-
-    class __Case(str, Enum):
-        # unverändert
-        KEEP = "KEEP"
-
-        # GROSSBUCHSTABEN
-        UPPER = "UPPER"
-
-        # kleinbuchstaben
-        LOWER = "LOWER"
-
-        # ZuFÄllIg
-        RANDOM = "RANDOM"
-
-    value: str
-
-    whitespace: __Whitespace = __Whitespace.REMOVE
-    special_chars: __SpecialChars = __SpecialChars.REMOVE
-    case: __Case = __Case.UPPER
-
-    @field_validator("whitespace", "case", mode="before")
-    def transform_from_str(cls, v) -> str:
-        return str(v).upper()
-
-    @property
-    def clean(self) -> str:
-        result = self.value
-
-        # Whitespace verarbeiten
-        if self.whitespace is TransformedString.__Whitespace.STRIP:
-            result = result.strip()
-
-        elif self.whitespace is TransformedString.__Whitespace.SPACE:
-            result = re.sub(string=result, pattern=r"\s+", repl=" ")
-
-        elif self.whitespace is TransformedString.__Whitespace.REMOVE:
-            result = re.sub(string=result, pattern=r"\s+", repl="")
-
-        # Sonderzeichen verarbeiten
-        if self.special_chars is TransformedString.__SpecialChars.REMOVE:
-            result = re.sub(string=result, pattern=r"[^a-zA-Z0-9\s]+", repl="")
-
-        # Groß-/Kleinschreibung verarbeiten
-        if self.case is TransformedString.__Case.UPPER:
-            result = result.upper()
-
-        elif self.case is TransformedString.__Case.LOWER:
-            result = result.lower()
-
-        elif self.case is TransformedString.__Case.RANDOM:
-            rnd = Random(self.value)
-
-            def randomcase(c: str) -> str:
-                if rnd.choice((True, False)):
-                    return c.upper()
-                return c.lower()
-
-            result = "".join(randomcase(c) for c in result)
-
-        return result
-
-
 class Site(BaseModel):
     model_config = ConfigDict(validate_default=True)
 
diff --git a/api/advent22_api/core/transformed_string.py b/api/advent22_api/core/transformed_string.py
new file mode 100644
index 0000000..3099abb
--- /dev/null
+++ b/api/advent22_api/core/transformed_string.py
@@ -0,0 +1,96 @@
+import re
+from enum import Enum
+from random import Random
+
+from pydantic import BaseModel, field_validator
+
+_RE_WHITESPACE = re.compile(
+    pattern=r"\s+",
+    flags=re.UNICODE | re.IGNORECASE,
+)
+_RE_SPECIAL_CHARS = re.compile(
+    pattern=r"[^a-zA-Z0-9\s]+",
+    flags=re.UNICODE | re.IGNORECASE,
+)
+
+
+class TransformedString(BaseModel):
+    class __Whitespace(str, Enum):
+        # unverändert
+        KEEP = "KEEP"
+
+        # Leerzeichen an Anfang und Ende entfernen
+        STRIP = "STRIP"
+
+        # whitespace durch Leerzeichen ersetzen
+        SPACE = "SPACE"
+
+        # whitespace entfernen
+        REMOVE = "REMOVE"
+
+    class __SpecialChars(str, Enum):
+        # unverändert
+        KEEP = "KEEP"
+
+        # Sonderzeichen entfernen
+        REMOVE = "REMOVE"
+
+    class __Case(str, Enum):
+        # unverändert
+        KEEP = "KEEP"
+
+        # GROSSBUCHSTABEN
+        UPPER = "UPPER"
+
+        # kleinbuchstaben
+        LOWER = "LOWER"
+
+        # ZuFÄllIg
+        RANDOM = "RANDOM"
+
+    value: str
+
+    whitespace: __Whitespace = __Whitespace.REMOVE
+    special_chars: __SpecialChars = __SpecialChars.REMOVE
+    case: __Case = __Case.UPPER
+
+    @field_validator("whitespace", "case", mode="before")
+    def transform_from_str(cls, v) -> str:
+        return str(v).upper()
+
+    @property
+    def clean(self) -> str:
+        result = self.value
+
+        # Whitespace verarbeiten
+        if self.whitespace is TransformedString.__Whitespace.STRIP:
+            result = result.strip()
+
+        elif self.whitespace is TransformedString.__Whitespace.SPACE:
+            result = _RE_WHITESPACE.sub(string=result, repl=" ")
+
+        elif self.whitespace is TransformedString.__Whitespace.REMOVE:
+            result = _RE_WHITESPACE.sub(string=result, repl="")
+
+        # Sonderzeichen verarbeiten
+        if self.special_chars is TransformedString.__SpecialChars.REMOVE:
+            result = _RE_SPECIAL_CHARS.sub(string=result, repl="")
+
+        # Groß-/Kleinschreibung verarbeiten
+        if self.case is TransformedString.__Case.UPPER:
+            result = result.upper()
+
+        elif self.case is TransformedString.__Case.LOWER:
+            result = result.lower()
+
+        elif self.case is TransformedString.__Case.RANDOM:
+            rnd = Random(self.value)
+
+            def randomcase(c: str) -> str:
+                if rnd.choice((True, False)):
+                    return c.upper()
+                return c.lower()
+
+            result = "".join(randomcase(c) for c in result)
+
+        return result