my $profile = {
  index  =>  {
    required  =>  [ qw(firstname surname address1 postcode email) ],
    optional  =>  [ qw(middlename address2 address3 address4) ],
    constraints  =>  {
      postcode   =>  '/^[A-Z]{1,2}\d[A-Z\d]?\s*\d[A-Z]{2}$/i',
      email      =>  {
        constraint  =>  sub {
          return valid_email($_[0]) && length($_[0]) <= 100;
        },
        params      =>  [ 'email' ],
    },
    constraint_regexp_map  =>  {
      '/name$/'     =>  '/(?=^.{0,25}$)[[:print:]]*$/i',
      '/^address/'  =>  '/(?=^.{0,50}$)[[:print:]]*$/i',
    },
  },
};