diff --git a/packages/redux-devtools-core/package.json b/packages/redux-devtools-core/package.json
index 6b3a139f..a51cebe3 100644
--- a/packages/redux-devtools-core/package.json
+++ b/packages/redux-devtools-core/package.json
@@ -40,6 +40,7 @@
     "d3-state-visualizer": "^1.3.4",
     "devui": "^1.0.0-6",
     "get-params": "^0.1.2",
+    "immutable": "^4.0.0-rc.12",
     "javascript-stringify": "^2.0.1",
     "jsan": "^3.1.13",
     "jsondiffpatch": "^0.4.1",