diff --git a/pubspec.yaml b/pubspec.yaml
index 77e6ee4..e9e02fd 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -9,6 +9,7 @@ environment:
 # Add regular dependencies here.
 dependencies:
   googleapis_grpc: ^1.0.28+routingonly
+  protobuf_wellknown: ^0.1.1
   # path: ^1.9.0
 
 dev_dependencies: