Custom routeParts handler is not being executed

Hi all!

I have a problem with a custom route. The route looks like this:

-
  name: 'Keyword page'
  uriPattern:    '{node}/{--filter.keyword}.html'
  defaults:
    '@package':    'Neos.Neos'
    '@controller': 'Frontend\Node'
    '@format':     'html'
    '@action':     'show'
    '--filter':
      '@package': ''
      '@subpackage': ''
      '@controller': ''
      '@action': 'index'
      '@format': 'html'
  routeParts:
    node:
      handler: 'Vendor\Vendor\Routing\FrontendNodeOfTypeRoutePartHandler'

And my custom route part handler FrontendNodeOfTypeRoutePartHandler looks like this:

<?php
namespace Vendor\Vendor\Routing;

use Neos\ContentRepository\Domain\Model\NodeInterface;
use Neos\Neos\Routing\FrontendNodeRoutePartHandler;

class FrontendNodeOfTypeRoutePartHandler extends FrontendNodeRoutePartHandler
{
    protected function resolveValue($node)
    {
        die('foo');
    }
}

Can someone tell me why my custom route part handler is never executed? What am I doing wrong?

How do you try to generate the URL/Link?

Or, easier yet: What is the resulting URL you get?