adding features

is it possible to add features like async programming and concurent feature like "https://kraken-php.com" framework? this php framework have great feature and performance which claim better than node js.

There are number of frameworks like that such as ReactPHP. There are platforms as well. Running Yii in such environment was possible since 1.1 but it’s not straightforward. Here’s discussion about more user-friendly support of it: https://github.com/yiisoft/yii2/issues/14064