BrowserSync + php server proxy: php requests time out

I'm trying to proxy a php server to BrowserSync. The BS config is just this, and I'm starting a php server with the following:

browserSyncConfig = {
    port: 3000,
    proxy: '127.0.0.1:8000'
}

php -S 127.0.0.1:8000

I'm using 127.0.0.1 instead of localhost as many suggested (with localhost all resources time out).

All resources load properly except for php-s, they are pending indefinitely. The result is the same with XAMPP, but strangely it works with Mongoose. What could be the problem with the php -s server?

via poisonborz