diff --git a/README.md b/README.md
index c93a624a..708ab8d6 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,8 @@ Tested with the following Keycloak versions:
 This tool will be maintained to stay compatible with Keycloak v11 and up, however, the default pages you will get 
 (before you customize it) will always be the ones of Keycloak v11.
 
+Install [Maven](https://maven.apache.org/) which is needed for the theme build process.
+
 This tool assumes you are bundling your app with Webpack (tested with 4.44.2) .
 It assumes there is a `build/` directory at the root of your react project directory containing a `index.html` file
 and a `build/static/` directory generated by webpack.