I'm running some tests and It seems that the dependency ( DEPENDS:=+opkg-bismark +opkg ) order respects the compilation but not the running order of post install scripts
cat  $${IPKG_INSTROOT}/etc/opkg.conf >>/tmp/log.txt
this file wasn't there and returned a post-install script error when running make.
According to http://wiki.openwrt.org/doc/devel/packages#dependency.types it should.
Any insights on this one?