diff --git a/README.md b/README.md
index 3ce8604..25c8c5d 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@
 
 **Heta** is a modeling language for quantitative systems pharmacology and systems biology.
 
-The current version is **0.4.5**.
+The current version is **0.4.6**.
 
 See also the [Heta video tutorial](https://hetalang.github.io/#/resources/?id=lesson-0-introduction)
 
diff --git a/changelog.md b/changelog.md
index 34a47bd..59c8119 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,11 @@
 # Change Log
 
+## 0.4.6
+
+- support `null` values of properties
+- add `#forceInsert` action
+- `#defineFunction` is not experimental anymore
+
 ## 0.4.5
 
 - use `0`, `1` together with `true`, `false` for boolean