diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4840eb6..b32aeca 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# [1.2.0](https://github.com/amplitude/experiment-go-server/compare/v1.1.3...v1.2.0) (2023-08-25)
+
+
+### Features
+
+* Automatic assignment Tracking ([#13](https://github.com/amplitude/experiment-go-server/issues/13)) ([96438e5](https://github.com/amplitude/experiment-go-server/commit/96438e5ac0fc091ea322aec02a4058829c859cc2))
+
 ## [1.1.3](https://github.com/amplitude/experiment-go-server/compare/v1.1.2...v1.1.3) (2023-08-04)
 
 
diff --git a/pkg/experiment/types.go b/pkg/experiment/types.go
index 5c76615..5aca5b6 100644
--- a/pkg/experiment/types.go
+++ b/pkg/experiment/types.go
@@ -1,6 +1,6 @@
 package experiment
 
-const VERSION = "1.1.3"
+const VERSION = "1.2.0"
 
 type User struct {
 	UserId             string                 `json:"user_id,omitempty"`