diff --git a/app.py b/app.py
index 961696d..a66bdce 100644
--- a/app.py
+++ b/app.py
@@ -432,55 +432,67 @@ def api_posts():
             cutoff_date = datetime.utcnow() - timedelta(days=time_filter_days)
             time_cutoff = cutoff_date.timestamp()
 
-        # Collect raw posts for filtering
-        raw_posts = []
-        for post_uuid, post_data in cached_posts.items():
-            # Apply time filter first if enabled
+        # ====================================================================
+        # START OF REFACTORED SECTION
+        # ====================================================================
+        
+        def _post_should_be_included(post_data):
+            """Check if a post passes all pre-filterset criteria."""
+            # Apply time filter
             if time_filter_enabled and time_cutoff:
-                post_timestamp = post_data.get('timestamp', 0)
-                if post_timestamp < time_cutoff:
-                    continue
-            # Apply community filter (before filterset)
+                if post_data.get('timestamp', 0) < time_cutoff:
+                    return False
+
+            # Apply community filter
             if community and post_data.get('source', '').lower() != community.lower():
-                continue
+                return False
 
-            # Apply platform filter (before filterset)
+            # Apply platform filter
             if platform and post_data.get('platform', '').lower() != platform.lower():
-                continue
+                return False
 
-            # Apply user's community preferences (before filterset)
+            # Apply user's community preferences
             if user_communities:
                 post_source = post_data.get('source', '').lower()
                 post_platform = post_data.get('platform', '').lower()
-                
-                # Check if this post matches any of the user's selected communities
-                matches_community = False
-                for selected_community in user_communities:
-                    selected_community = selected_community.lower()
-                    # Match by exact source name or platform name
-                    if (post_source == selected_community or 
-                        post_platform == selected_community or
-                        selected_community in post_source):
-                        matches_community = True
-                        break
-                
-                if not matches_community:
-                    continue
+                if not any(
+                    post_source == c or post_platform == c or c in post_source
+                    for c in user_communities
+                ):
+                    # ====================================================================
+                    # MODIFICATION: Add logging here
+                    # ====================================================================
+                    logger.error(
+                        f"Post filtered out for user {current_user.id if current_user.is_authenticated else 'anonymous'}: "
+                        f"Community mismatch. Platform='{post_platform}', Source='{post_source}', "
+                        f"User Communities={user_communities}"
+                    )
+                    # ====================================================================
+                    return False
 
-            # Apply search filter (before filterset)
+            # Apply search filter
             if search_query:
                 title = post_data.get('title', '').lower()
                 content = post_data.get('content', '').lower()
                 author = post_data.get('author', '').lower()
                 source = post_data.get('source', '').lower()
-
                 if not (search_query in title or
                        search_query in content or
                        search_query in author or
                        search_query in source):
-                    continue
+                    return False
+            
+            return True
 
-            raw_posts.append(post_data)
+        # Collect raw posts using a clean, declarative list comprehension
+        raw_posts = [
+            post_data for post_data in cached_posts.values()
+            if _post_should_be_included(post_data)
+        ]
+
+        # ====================================================================
+        # END OF REFACTORED SECTION
+        # ====================================================================
 
         # Apply filterset using FilterEngine
         filtered_posts = filter_engine.apply_filterset(raw_posts, filterset_name, use_cache=True)