public function declareRoutes(WordPressRouteCollector $r) {
        $r->addGroup('/v3', function (WordPressRouteCollector $r) {
            // REST handlers
            $item = new API\Item($this->master);
            $cart = new API\Cart($this->master);
            $wishlist = new API\Wishlist($this->master);
            $validation = new API\Validation($this->master);

            // route guards and middleware
            $isLoggedIn = [$validation, 'isLoggedIn'];
            $maybeClearCart = [$wishlist, 'maybeClearCart'];
            $beforeRouteEnter = [$this, 'beforeRouteEnter'];

            // REST routes
            $r->post('/item/addToWishlist', [$item, 'postToWishlist'], [$beforeRouteEnter]);
            $r->post('/cart/addToWishlist', [$cart, 'postToWishlistBySerial'], [$beforeRouteEnter]);
            $r->post('/cart/batchDelete', [$cart, 'batchDelete'], [$beforeRouteEnter]);
            $r->post('/wishlist/delete/{itemId}', [$wishlist, 'delete'], [$beforeRouteEnter, $isLoggedIn]);
            $r->post('/wishlist/batchDelete', [$wishlist, 'batchDelete'], [$beforeRouteEnter, $isLoggedIn]);
            $r->post('/wishlist/addToCart/{itemId}', [$wishlist, 'addToCart'], [$beforeRouteEnter, $isLoggedIn, $maybeClearCart]);
            $r->post('/wishlist/batchAddToCart', [$wishlist, 'batchAddToCart'], [$beforeRouteEnter, $isLoggedIn, $maybeClearCart]);
        });
    }