gistfile1.txt

# MyClass.pm

package Cloud::Meta::Attribute::Trait::UserData;
use Moose::Role;

has 'is_userdata' => (
    is => 'ro',
    isa => 'Bool',
    default => 1,
);

package Moose::Meta::Attribute::Custom::Trait::UserData;
sub register_implementation { 'Cloud::Meta::Attribute::Trait::UserData' }

use MooseX::Declare;

class MyClass {
    # ...

---
# MyClass/Cmd.pm
package MyClass::Cmd;
use Moose;
use MooseX::Getopt;
extends qw(MooseX::App::Cmd);

---
# MyClass/Cmd/Command/start.pm
package MyClass::Cmd::Command::start;
use Moose;
use Carp;

extends qw(MooseX::App::Cmd::Command MyClass);

sub execute {
    my ( $self, $opt, $args ) = @_;
    # ...
}