file server content type headers

README.md

@@ -73,6 +73,11 @@ router.serveDirectory('dirWithIndexHtml', '/indexes', {showIndex: true});
 
 ### File-based Routing
 
+**Note:** _This is an experimental feature and may change in the future.
+Currently, JSR does not support dynamic imports for external modules in Deno. In
+order to use this feature, you will need to install as an HTTP module (available
+soon)._
+
 ```ts
 import { FileRouter } from "@bearmetal/router";