diff --git a/docs/extensions/README.md b/docs/extensions/README.md
index 006b800..abd0435 100644
--- a/docs/extensions/README.md
+++ b/docs/extensions/README.md
@@ -30,6 +30,12 @@ There are none yet, so consider this section a placeholder
 
 ### Checkers
 
+- [askiiart/updog-http_checker](https://git.askiiart.net/askiiart/updog-http_checker) - a basic checker for HTTP stuff
+
 ### Alerts
 
 ### Logging
+
+## Extension Development
+
+Extensions are simple to develop, check the other markdown files in this directory for details.