diff --git a/config/retriex/language.yaml b/config/retriex/language.yaml
index 68da7b0..f4089a7 100644
--- a/config/retriex/language.yaml
+++ b/config/retriex/language.yaml
@@ -71,6 +71,15 @@ parameters:
       - tc
       - '0,02'
 
+    normalization:
+      # Generic language normalization tables. Keep these in YAML so PHP code
+      # executes normalization logic without owning language-specific lists.
+      ascii_transliteration:
+        ä: ae
+        ö: oe
+        ü: ue
+        ß: ss
+
     stopword_groups:
       de_core:
         - der