Since v0.5, Redstone.dart is built around the Shelf framework. That means you can use any Shelf middleware or handler in your app:

main() {
  //Middlewares registered with addShelfMiddleware() will be invoked before
  //any interceptor or route.
  app.addShelfMiddleware(...);
  app.addShelfMiddleware(...);

  //The handler registered with setShelfHandler() will be invoked when all
  //interceptors are completed, and there is no route for the requested URL.
  app.setShelfHandler(...);

  app.setupConsoleLog();
  app.start();
}

For example, you can use shelf_static to serve static files:

import 'package:redstone/redstone.dart' as app;
import 'package:shelf_static/shelf_static.dart';

main() {
  app.setShelfHandler(createStaticHandler("../web", 
                                          defaultDocument: "index.html", 
                                          serveFilesOutsidePath: true));
  app.setupConsoleLog();
  app.start();
}