diff --git a/package.json b/package.json
index a3feccf..341b1be 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@oomol-lab/ovm",
-  "version": "2.1.1",
+  "version": "2.2.0",
   "description": "oomol virtual machine",
   "main": "src/index.ts",
   "module": "src/index.ts",