diff --git a/vg/core.py b/vg/core.py
index e5e7784..04b3d10 100644
--- a/vg/core.py
+++ b/vg/core.py
@@ -16,6 +16,7 @@
     "signed_angle",
     "rotate",
     "scale_factor",
+    "aligned_with",
     "orient",
     "almost_zero",
     "almost_unit_length",