diff --git a/RELEASE_NOTES.rst b/RELEASE_NOTES.rst
index 69c7253378..c60dde375f 100644
--- a/RELEASE_NOTES.rst
+++ b/RELEASE_NOTES.rst
@@ -9,6 +9,7 @@ Unreleased
 Highlights:
 
 * Implemented Phaser-servo. This requires recent gateware on Phaser.
+* HDF5 attributes can be attached to datasets using ``set_dataset_metadata()``.
 
 
 ARTIQ-7