diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7451af2..26855d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## Unrelease
+
+* The `Duration` class is final again (and will stay that way) [#2](https://github.com/jeromegamez/duration-php/issues/2)
+
 ## 2.0 - 2019-01-25
 
 * The `Duration` class is now extensible instead of macroable
diff --git a/src/Duration.php b/src/Duration.php
index 0f25103..def518c 100644
--- a/src/Duration.php
+++ b/src/Duration.php
@@ -8,7 +8,7 @@
 use DateTimeImmutable;
 use Gamez\Duration\Exception\InvalidDuration;
 
-class Duration implements \JsonSerializable
+final class Duration implements \JsonSerializable
 {
     private const NONE = 'PT0S';