diff --git a/README.md b/README.md
index b684881..ef63336 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,9 @@
 
 # <img src="doc/logo-display-only.svg" width="50%" style="display: block; margin: 0 auto;" alt="Rakenne" />
 
-Rakenne is a database modeling tool for command line.
+Rakenne is a database modeling tool for command line written in Crystal.
+
+For now, It is a toy project to improve author's skills with the language and its various libraries. **It is not supposed to work (yet). Please don't use it in production.** :warning:
 
 Note: _rakenne_ means _structure_ in Finnish.