diff --git a/yesod-core/ChangeLog.md b/yesod-core/ChangeLog.md
index 5952081a..6e80a859 100644
--- a/yesod-core/ChangeLog.md
+++ b/yesod-core/ChangeLog.md
@@ -1,3 +1,7 @@
+## 1.6.4
+
+* Add `fileSourceByteString` [#1503](https://github.com/yesodweb/yesod/pull/1503)
+
 ## 1.6.3
 
 * Add missing export for `SubHandlerFor`