Making the authentifaction provider work

I've updated your project so the listener works but there is still a lot of work that needs to be done! I'm not an expert on this so I can't help you how to procede now.

I recommend using xdebug to see what happens there exactly:
Set a breakpoint in the classes.php at namespace Symfony\Component\Security\Http
class Firewall at foreach ($listeners as $listener) {
https://github.com/symfony/symfony/blob/v2.1.7/src/Symfony/Component/Security/Http/Firewall.php#L63

It's line 5799 in my classes.php.

First step would be working on the Token..add a getUsername() method to identify the user and make sure the user gets loaded ($user = $this->userProvider->loadUserByUsername($token->getUsername()); in WordnikProvider). I do my API call in the authenticate method.

Good luck!