diff --git a/CHANGELOG.md b/CHANGELOG.md
index 917c9889..d9b859ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## 1.5.5 - 2019-05-23
+- Improved `Signature`.
+
+
 ## 1.5.4 - 2019-05-22
 - Updated `Endpoints`.
 - Fixed `Content-Type` in header.