updated README

README.md

@@ -19,3 +19,12 @@ want to process.
 
 Articles are cached in /tmp to reduce bandwidth usage and script-processing
 time.
+
+Usage (Docker)
+--------------
+
+A [containerized version](https://gitlab.alfter.us/salfter/fullrss/container_registry)
+built on php/fpm-alpine is available.  You could spin it up with
+/var/www/html in a separate volume, but since this is just a single PHP
+script, you can probably get away without it, depending on your webserver.
+Mounting /tmp to a tmpfs instance is probably a good idea, too.