JSX pragma, flow config and vhtml

Hi,

I tried vhtml and it looks fine.

However, to integrate it in my stack I need to make it properly working with .flowconfig
* what's the pragma @jsx syntax to use with vhtml?
* is there a way to alter .flowconfig to 'prepend 'automatically this @jsx tag to all files ?

Currently I'm using : rollup + buble + flow + vhtml

Thanks for help.