diff --git a/tnc/helpers.py b/tnc/helpers.py
index f2b12cc9..6591f273 100644
--- a/tnc/helpers.py
+++ b/tnc/helpers.py
@@ -9,6 +9,7 @@ import time
 import crcengine
 import static
 import structlog
+import numpy as np
 
 log = structlog.get_logger("helpers")