Add a simple Controller.

lib/MyApp.pm

@@ -6,9 +6,7 @@ sub startup ($self) {
    # This route gets an explicit name, else it's an empty string.  A
    # route's default name seems to come from '/path' with the leading
    # '/' removed.
-   $r->get(
-      '/' => sub ($c) { $c->render(template => 'index'); }
-   )->name('/');
+   $r->get('/')->to('index#index')->name('/');
    $r->get(
       '/foo' => sub ($c) {
          my $value = $c->param('param1');

lib/MyApp/Controller/Index.pm

@@ -0,0 +1,8 @@
+package MyApp::Controller::Index;
+use Mojo::Base 'Mojolicious::Controller', -signatures;
+
+sub index ($self) {
+   $self->render(template => 'index');
+}
+
+1;