diff --git a/CHANGELOG.md b/CHANGELOG.md
index a87ce60..221cc26 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# v1.1.1 (2019-02-12)
+
+## Features
+
+* Improved documentation for v1.1.0
+
 # v1.1.0 (2019-02-12)
 
 ## Bug Fixes
diff --git a/README.md b/README.md
index 6072b60..dd569be 100644
--- a/README.md
+++ b/README.md
@@ -30,11 +30,14 @@ Make sure you catch the errors in production!
 
 See the changelog in the seperate file for bug fixes, new features and breaking changes: [Changelog](CHANGELOG.md)
 
+> Tip: At version 1.1.0 we introduced some soft breaking changes. 
+`undefined` is an invalid value now for serializing or deserializing. 
+If you are working with TypeScript, you might receive some type issues after the update to v1.1.0.
+This is due to the addition of generics; they now help the compiler to detect invalid return types in the serialize and deserialize methods.
+
 > Tip: Starting from version 1.0.6, we recommend to use unique class identifiers in the `@JsonObject` decorator. 
 Read below how to use the decorators properly.
 
-> Tip: Version 1.0.0 has several breaking changes. When upgrading from `json2typescript` < 1.0.0, please make sure you fix these issues.
-
 ---
 
 # Getting started