Test.pm

package Example::Controller::Register;

use Moose;
use MooseX::MethodAttributes;
use Example::Syntax;

extends 'Example::ControllerPerRequest',
  'Example::ViewModelController';

has registration => (
  is => 'ro',
  lazy => 1,
  required => 1,
  default => sub($self) { $self->ctx->users->registration },
);

sub root :Chained(/root) PathPart(register) Args(0) Does(Verbs) View(Components::Register)  ($self, $c) {
  return $c->redirect_to_action('#home') && $c->detach if $c->user->registered;
}

  sub GET :Action ($self, $c) { return $c->res->code(200) }

  sub POST :Action RequestModel(RegistrationRequest) ($self, $c, $request) {    
    $self->registration->register($request);  ## Avoid DBIC specific API
    return $self->registration->valid ?
      $c->redirect_to_action('#login') :
        $c->res->code(400);
  }

__PACKAGE__->meta->make_immutable;
__PACKAGE__->config(view_model=>'RegistrationView');

package MyApp::Model::RegistrationView;

use Moose;

extends 'Catalyst::Model::ViewModel';

has 'registration' => (is=>'ro', required=>1);

__PACKAGE__->meta->make_immutable;
__PACKAGE__->config(
  build => {
    registration => 'Controller',   ## Maybe better to use meta foo and just copy
  },
);

package Example::HTML::Components::Register;

use Moo;
use Example::HTML::Components 'Layout', 'FormFor';
use Valiant::HTML::TagBuilder ':html';
use Example::Syntax;

with 'Valiant::HTML::Component';
with 'CatalystX::ControllerAttributes'; # map init_args to controller attributes

has 'ctx' => (is=>'ro', required=>1);
has 'registration' => (
  is => 'ro', 
  required => 1, 
  lazy => 1, 
  default => sub($self) {
    return $self->ctx->controller->attribute_value_for_view('registration')
   },
);

__PACKAGE__->config(
  build => {
    registration => 'Controller',
  },
);