docs: use a custom directory for serving static files (#334)

Author: felangel

docs/docs/basics/serving-static-files.md

@@ -4,7 +4,11 @@ sidebar_position: 6
 
 # Serving Static Files 📁
 
-Dart Frog supports serving static files including images, text, json, html, and more. To serve static files, place the files within the `public` directory at the root of the project.
+Dart Frog supports serving static files including images, text, json, html, and more.
+
+## Overview 🚀
+
+To serve static files, place the files within the `public` directory at the root of the project.
 
 For example, if you create a file in `public/hello.txt` which contains the following:
 
@@ -33,3 +37,25 @@ In production, only files that are in the `/public` directory at build time will
 :::caution
 Be sure not to have a static file with the same name as a file in the `/routes` directory as this will result in a conflict.
 :::
+
+## Using a Custom Directory ✨
+
+Even though Dart Frog uses the `public` directory for serving static files by default, you can also specify a custom directory by creating a [custom entrypoint](/docs/advanced/custom_entrypoint).
+
+Create a `main.dart` at the root of your project with the following contents:
+
+```dart
+import 'dart:io';
+
+import 'package:dart_frog/dart_frog.dart';
+
+Future<HttpServer> run(Handler handler, InternetAddress ip, int port) {
+  const customStaticFilePath = 'api/static';
+  final cascade = Cascade()
+      .add(createStaticFileHandler(path: customStaticFilePath))
+      .add(handler);
+  return serve(cascade.handler, ip, port);
+}
+```
+
+In the above example, we're using `api/static` as our static file directory but you can specify a path to any directory for Dart Frog to use.