diff --git a/README.md b/README.md
index 6053e6d..ac6f67b 100644
--- a/README.md
+++ b/README.md
@@ -2,3 +2,11 @@
 *host static sites backed by an s3 bucket*
 
 configuration via environment variables:
+* `BIND` (default `:5000`) address:port to bind to. Address may be blank to bind to all addresses.
+* `S3_ENDPOINT` the S3 server endpoint to use
+* `ACCESS_KEY_ID` S3 access key
+* `SECRET_ACCESS_KEY` S3 access key
+
+To serve a site with this software, make an S3 bucket named the domain you'll be serving.
+* `index.html` will be served for requests to the root.
+* There is currently no support for custom 404 pages