Ok so it takes 4:27 on my machine. I did not realize minification was that slow.
4:27 with minification enabled and 1:17 without so we can hope for a 2:30/3:00 in the production system if we disable it.

What I propose is to do a two stage work:

• build the site wo minification and sync
• follow up by a minification step afterwards

This way, we get the fast deploy and are minified within 15 minutes.

The problem is if someone finds a issue quickly and restart a build, one would need to manually stop the slow minification job. So maybe we should do it only at night once a day?