diff --git a/lambda-runtime-api-client/src/lib.rs b/lambda-runtime-api-client/src/lib.rs
index 3753dedf..9703ecd2 100644
--- a/lambda-runtime-api-client/src/lib.rs
+++ b/lambda-runtime-api-client/src/lib.rs
@@ -1,5 +1,6 @@
 #![deny(clippy::all, clippy::cargo)]
 #![warn(missing_docs, nonstandard_style, rust_2018_idioms)]
+#![warn(clippy::multiple_crate_versions)]
 
 //! This crate includes a base HTTP client to interact with
 //! the AWS Lambda Runtime API.