diff --git a/README.md b/README.md
index ae1b743..9a83ce5 100644
--- a/README.md
+++ b/README.md
@@ -54,8 +54,11 @@ Triggering indexing is transparent once the app is installed and happens on the
 - unpublishing a post (remove a record)
 - deleting a post (remove a record)
 
+# Compatibility
+Tested against Ghost 1.x.x releases.
+
 # Roadmap
 
 - Switching to [fragment indexing](https://github.com/mlbrgl/kirby-algolia#principle).
 - Bulk indexing existing articles.
-- Upgrade to App API when available, to remove core hacking and simplify the installation process.
\ No newline at end of file
+- Upgrade to App API when available, to remove core hacking and simplify the installation process.