diff --git a/package.json b/package.json
index 34cdb73..079e02a 100644
--- a/package.json
+++ b/package.json
@@ -61,7 +61,9 @@
     "tslib": "^1.0.0",
     "use-sidecar": "^1.0.1"
   },
-  "sideEffects": false,
+  "sideEffects": [
+    "**/sidecar.js"
+  ],
   "resolutions": {
     "typescript": "^3.0.0"
   }