I know that a typical .deb file contains three files:
debian-binary control.tar.gz data.tar.gz
and that some are xz compressed instead of gzip (control.tar.xz, data.tar.xz).
What are other compression supported for debian files? And how does debian installer knows which decompression to use?
If I want to add support for another compression (for example, zopfli - https://github.com/google/zopfli). Is there source code for debian installer available which I could modify to make this addition possible?