gistfile1.php

<?php

interface UserFetcher {
    /**
     * Fetch a User by it's ID
     * @param $id
     * @return mixed
     */
    public function fetch($id);
}

class EloquentUserFetcher implements UserFetcher {
    /**
     * Fetch a User by it's ID
     * @param $id
     * @return mixed
     */
    public function fetch($id)
    {
        return User::find($id);
    }
}

class CacheUserFetcherDecorator implements UserFetcher {
    /**
     * @var UserFetcher
     */
    protected $fetcher;

    public function __construct(UserFetcher $fetcher)
    {
        $this->fetcher = $fetcher;
    }

    /**
     * Fetch a User by it's ID
     * @param $id
     * @return mixed
     */
    public function fetch($id)
    {
        return cache()->get("user-{$id}", function () use ($id) {
            return $this->fetcher->fetch($id);
        });
    }
}

$fetcher = new CacheUserFetcherDecorator(new EloquentUserFetcher);