diff --git a/overviewer_core/tileset.py b/overviewer_core/tileset.py
index 10dc8d8..9d886de 100644
--- a/overviewer_core/tileset.py
+++ b/overviewer_core/tileset.py
@@ -29,6 +29,7 @@ from PIL import Image
 
 from .util import iterate_base4, convert_coords, unconvert_coords
 from .optimizeimages import optimize_image
+import c_overviewer
 
 """