diff --git a/packages/firestore/externs.json b/packages/firestore/externs.json
index d597bfb77a9..74d91e8f910 100644
--- a/packages/firestore/externs.json
+++ b/packages/firestore/externs.json
@@ -21,6 +21,7 @@
     "packages/component/dist/src/component_container.d.ts",
     "packages/logger/dist/src/logger.d.ts",
     "packages/webchannel-wrapper/src/index.d.ts",
+    "packages/util/dist/src/crypt.d.ts",
     "packages/util/dist/src/environment.d.ts",
     "packages/firestore/src/protos/firestore_proto_api.d.ts",
     "packages/firestore/src/util/error.ts",