diff --git a/README.md b/README.md
index b2c846c..fe46b80 100644
--- a/README.md
+++ b/README.md
@@ -20,11 +20,13 @@ Complete, valid yaml frontmatter for a page:
 ```
 ---
 title: required string
-permalink: required string
+permalink: optional string
 data: optional anything
 ---
 ```
 
+If a permalink is not specified, the resultant file will have the same stem as the source file, and the extension `html`.
+
 Besides the above, the following variables can be accessed from the global scope in the template:
 - `incoming` - a list of objects in the form of `{ title, permalink, data, id }` that link to this page
 - `id` - a trimmed, lower-cased version of the current page's title used internally to reference pages