diff --git a/pubspec.yaml b/pubspec.yaml
index 863434f3..3b7dde63 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -7,6 +7,7 @@ environment:
   flutter: ">=2.0.0"
 
 dependencies:
+  collection: ^1.16.0
   crypto: ^3.0.0
   flutter_webrtc: ^0.9.1
   intl: ^0.17.0