diff --git a/README.md b/README.md
index 5b03572..00c223c 100644
--- a/README.md
+++ b/README.md
@@ -12,3 +12,5 @@ Custom Docker image based on Debian stable slim, with PHP Sury apt repo, and the
   - php8.3-readline 
   - php8.3-xml 
   - php8.3-zip 
+
+Build is made on 'catthehacker/ubuntu:act-latest' image (which already has curl / git / docker-cli installed).