diff --git a/packages/core/package.json b/packages/core/package.json
index f9849cc158..f79e4123c1 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -17,7 +17,7 @@
   },
   "peerDependencies": {
     "rxjs": "^6.0.0-beta.4",
-    "zone.js": "^0.8.4"
+    "zone.js": "~0.8.20"
   },
   "repository": {
     "type": "git",