diff --git a/js/snapUtils.ts b/js/snapUtils.ts
index e78147e9..50555851 100644
--- a/js/snapUtils.ts
+++ b/js/snapUtils.ts
@@ -13,7 +13,7 @@ interface BoundingBox {
   height: number;
 }
 
-interface Box extends Point {
+export interface Box extends Point {
   width: number;
   height: number;
 }