diff --git a/README.md b/README.md
index 94737d9..f1e90fd 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,9 @@
 # Flysystem adapter for AsyncAws S3
 
+**CAUTION**: this adapter is deprecated. Use the
+[league/flysystem-async-aws-s3](https://packagist.org/packages/league/flysystem-async-aws-s3)
+package instead.
+
 ![](https://github.com/async-aws/flysystem-s3/workflows/Tests/badge.svg?branch=master)
 ![](https://github.com/async-aws/flysystem-s3/workflows/BC%20Check/badge.svg?branch=master)