diff --git a/README.md b/README.md
index fe769ef..88aa9e1 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,9 @@
 
 Use your tablet as your osu digitizer! 
 
+> [!WARNING]
+> 3.0 is currently in preview version, and there may be incompatible changes in the transmission protocol. Please be sure to update the server and client at the same time.
+
 ## Help
 
 (WIP)