grav CMS on OpenBSD w/ chrooted fpm and nginx
Just in case somebody else is getting the cannot resolve getgrav.com error: just copy /etc/resolv.conf into the chroot:
mkdir /var/www/etc
cp /etc/resolv.conf /var/www/etc/
And I already feared that I need to create /dev/random and shit like that. Damn it that took too long to find out.