diff --git a/backend/chat_memory.py b/backend/chat_memory.py
index a9fcc8e..59fde0f 100644
--- a/backend/chat_memory.py
+++ b/backend/chat_memory.py
@@ -15,33 +15,6 @@ DEFAULT_MEMORY_TOP_K = 4
 DEFAULT_MEMORY_CONTEXT_CHARS = 3600
 _TOKEN_RE = re.compile(r"[\w][\w'_-]*", re.UNICODE)
 _THINK_RE = re.compile(r"<think(?:ing)?>.*?</think(?:ing)?>", re.IGNORECASE | re.DOTALL)
-_STOPWORDS = {
-    "about", "again", "also", "and", "are", "but", "can", "could", "did", "does", "for",
-    "from", "had", "has", "have", "how", "into", "just", "like", "more", "not", "now",
-    "our", "out", "over", "please", "should", "that", "the", "then", "there", "this",
-    "was", "were", "what", "when", "where", "which", "with", "would", "you", "your",
-    "all", "anything", "chat", "chats", "conversation", "conversations", "discuss",
-    "discussed", "everything", "list", "me", "talk", "talked", "tell", "topic", "topics",
-    "aber", "als", "auch", "auf", "aus", "bei", "bin", "bis", "das", "dem", "den",
-    "der", "des", "die", "ein", "eine", "einem", "einen", "einer", "erzaehl", "erzähl",
-    "erzähle", "für", "ging", "hat", "ich", "ist", "letzte", "letzten", "letztes", "mir",
-    "mit", "nicht", "oder", "sich", "sind", "und", "uns", "über", "ueber", "von",
-    "war", "was", "wie", "wir", "worum", "zu", "zum", "zur",
-}
-_LAST_CONVERSATION_RE = re.compile(
-    r"\b(last|latest|previous|prior)\s+(chat|conversation|session)\b"
-    r"|\b(letzte[sn]?|vorherige[sn]?)\s+(gespr[aä]ch|chat|unterhaltung)\b"
-    r"|\bworum\s+ging\s+es\s+im\s+letzte[sn]?\s+gespr[aä]ch\b",
-    re.IGNORECASE,
-)
-_QUERY_EXPANSIONS = {
-    "music": ["song", "songs", "album", "albums", "artist", "artists", "band", "bands", "lied", "lieder", "musik"],
-    "musik": ["music", "song", "songs", "album", "albums", "artist", "artists", "band", "bands", "lied", "lieder"],
-    "song": ["music", "songs", "lied", "lieder", "musik"],
-    "songs": ["music", "song", "lied", "lieder", "musik"],
-    "lied": ["music", "musik", "song", "songs", "lieder"],
-    "lieder": ["music", "musik", "song", "songs", "lied"],
-}
 
 
 def ensure_chat_memory_schema(engine) -> None: