diff --git a/package.json b/package.json
index a1c5ae5a..0ab2dcda 100644
--- a/package.json
+++ b/package.json
@@ -36,6 +36,6 @@
     "semantic-ui-less": "^2.2.4"
   },
   "dependencies": {
-    "pxt-core": "0.12.20"
+    "pxt-core": "0.12.21"
   }
 }