update readme

README.md

@@ -160,6 +160,23 @@ pkgs.fetchFromSteam {
 }
 ```
 
+### `mkNginxServer`
+
+creates a shell script that launches nginx in the foreground as the current user. the nginx is
+configured to run an http server on `localhost:8080` with the given `siteConfig`
+
+example:
+```nix
+pkgs.mkNginxServer {
+  siteConfig = ''
+    location / {
+      root path/to/development_site_root;
+      error_page 404 /404.html;
+    }
+  '';
+}
+```
+
 ## licensing
 
 this repository is NOT licensed under a "standard" FOSS license. instead, it uses