diff --git a/backend/compiler.py b/backend/compiler.py
index 1aa7c54..f4dcde7 100644
--- a/backend/compiler.py
+++ b/backend/compiler.py
@@ -1,6 +1,6 @@
 # Article compilation module - Groups and merges related articles
 
-from typing import List, Dict, Tuple
+from typing import List, Dict, Tuple, Optional
 from sklearn.feature_extraction.text import TfidfVectorizer
 from sklearn.metrics.pairwise import cosine_similarity
 from loguru import logger