public function getBehavior($slug, $strategy = self::DEFAULT_STRATEGY)
    {
        $this->logger->debug('Swivel - Creating new behavior.', compact('slug'));
        if ($strategy === static::DEFAULT_STRATEGY) {
            $strategy = $slug;
            $slug = static::DEFAULT_SLUG;
        }

        if (!is_callable($strategy)) {
            if (is_string($strategy)) {
                $strategy = explode('::', $strategy);
            }
            if (!isset($strategy[0], $strategy[1]) || !method_exists($strategy[0], $strategy[1])) {
                throw new \LogicException('Invalid callable passed to Zumba\Swivel\Builder::getBehavior');
            }
            $closure = function () use ($strategy) {
                return call_user_func_array($strategy, func_get_args());
            };
            $strategy = $closure->bindTo(null, $strategy[0]);
        }
        $slug = empty($slug) ? $this->slug : $this->slug.Map::DELIMITER.$slug;

        return new Behavior($slug, $strategy, $this->logger);
    }