diff --git a/CHANGELOG.md b/CHANGELOG.md
index 88baadf..60713b8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 ### Changed
 
  - B-tree performance improvements (#143 and #144)
+ - HashMap performance improvements (#131)
  - Removed the unused refpool dependency. Breaking change (although unlikely in practice). (#141)
 
 ## [6.1.0] - 2025-09-09