# define packages
package: btrfs-progs
package: filesystem
-package: dhclient
+package<=f21: dhclient
+package>=f22: dhcp-client
package: bash
package: coreutils
package: iputils
package: kernel
+package>=f23: kernel-modules kernel-modules-extra
+package>=f24: systemd-udev
package: bzip2
package: diffutils
package: logrotate