diff --git a/README.md b/README.md
index 1b0729f..337c85b 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,8 @@
 
 **WARNING: Latest `raygui` from master branch is always aligned with latest `raylib` from master branch. Make sure to use the appropiate versions.**
 
+**WARNING: Master branch now contains raygui 4.0-dev, it is an API-BREAKING reddesign from previous versions (3.x), now all functions are more consistent and coherent, you can read the details about this breaking change in issue [283](https://github.com/raysan5/raygui/issues/283)**
+
 ## features
 
  - **Immediate-mode gui, no retained data**