Here's a README.

To get a repo working:
1. pppkg -h
2. edit the resulting /etc/pppkg.json
3. pppkg -u

Some notes:
"apt-get install" == "pppkg -di"
"dpkg -i" == "pppkg -i"

To remove a package, pppkg -r.
To list packages, pppkg -l.
To download a package, pppkg -d.

-f = force, -v = increase verbosity level, -C = prefer compilation to binaries
-P [prefix folder] - oh you chrooters you, set the prefix for pppkg's files