debuilding

Meilix has is made of build file and metapackages. Build file is responsible for executing commands and successfully implementing the work of metapackages.

Metapackages in Meilix
Name of metapackages used in Meilix are: meilix-artwork, meilix-default-settings.

meilix-default-settings

meilix-default-settings have 3 major folders debian, etc and usr and a Makefile. We are only concerned with etc and usr folder here.
etc and usr folders are folders in which if changes are made that can be seen the ISO. One can assume this as two folders present in the root folder of a Linux Distro.

Its directory is like this:

meilix-artwork

meilix-artwork has 1 main folder named as usr which contain share folder in which plymouth configuration is made. One can make changes here and it will directly seen in the Linux Distro.

Its directory looks like this:

How these meta packages actually work?
To get the answer one has to jump into the debian folder of any of the metapackage. It contains a control file. This contains information of the metapackages.

Source: meilix-default-settings
Section: x11
Priority: extra
Maintainer: meilix <vanhonit@gmail.com>
Build-Depends: debhelper (>= 8.0.0)
Standards-Version: 3.9.2
Homepage: http://mbm.vn

Package: meilix-default-settings
Architecture: all
Depends: ${shlibs:Depends}, ${misc:Depends}
Description: default settings for meilix
 Various system settings tailored for meilix.

One can update the metapackage from here and tweak with its depends. One come to know about the maintainer of the metapackage which can contacted in case of any issue. We can also know for which architecture this metapackage is made and about its description.
The whole debian does the work but after making any changes in the metapackage, it needs to be rebuild which is performed by debuild.sh. This is how a metapackages in Meilix works.

References:
Linux Metapackages – Matthartley from linux.com
Creating a Metapackage – Ajmitch from askubuntu.com