How to access mac localhost from an iOs device with webpack-dev-server?

For local development, I try to access the mac localhost from an iOs device.

The mac and the iPad are conected to the same network (respectively with ethernet and wifi). The firewall is off on the computer.

From the terminal, I run webpack-dev-server on the current project and it is visible in the browser at http://localhost:8080

I try to access it on the iPad at http://my-ip-address:8080 but "safari could not open the page because the server stopped responding" (where my-ip-address is either http://my-mac.local or http://192.168.0.40)

How can I access localhost from the iPad?