diff --git a/package/package.json b/package/package.json
index 22f5049..af0d3e4 100644
--- a/package/package.json
+++ b/package/package.json
@@ -10,6 +10,6 @@
     "prepare": "npm run build"
   },
   "devDependencies": {
-    "typescript": "^2.4"
+    "typescript": "3.5"
   }
 }