diff --git a/app.py b/app.py
index 6f73f21..cfe316b 100644
--- a/app.py
+++ b/app.py
@@ -209,19 +209,36 @@ def _is_same_origin():
         return referer.startswith(base_url)
     return False
 
+def _ensure_rate_limits_table(conn):
+    """Create the rate_limits table if it doesn't exist (migration safety net)."""
+    conn.execute('''
+        CREATE TABLE IF NOT EXISTS rate_limits (
+            ip_address    TEXT,
+            timestamp     REAL,
+            PRIMARY KEY (ip_address, timestamp)
+        )
+    ''')
+    conn.execute('CREATE INDEX IF NOT EXISTS idx_rate_limit_ts ON rate_limits(timestamp)')
+    conn.commit()
+
 def _check_rate_limit(remote_ip, key_prefix='rl', window=600, limit=10):
     """Generic rate limiting via SQLite. Window is in seconds."""
     now_ts = time.time()
     conn = get_db_connection()
     try:
-        count = conn.execute(
-            'SELECT COUNT(*) FROM rate_limits WHERE ip_address = ? AND timestamp > ?',
-            (f"{key_prefix}:{remote_ip}", now_ts - window)
-        ).fetchone()[0]
-        
+        try:
+            count = conn.execute(
+                'SELECT COUNT(*) FROM rate_limits WHERE ip_address = ? AND timestamp > ?',
+                (f"{key_prefix}:{remote_ip}", now_ts - window)
+            ).fetchone()[0]
+        except sqlite3.OperationalError:
+            # Table missing (pre-migration DB) — create it and proceed.
+            _ensure_rate_limits_table(conn)
+            count = 0
+
         if count >= limit:
             return False
-        
+
         conn.execute('INSERT INTO rate_limits (ip_address, timestamp) VALUES (?, ?)', (f"{key_prefix}:{remote_ip}", now_ts))
         conn.commit()
         return True