I contribute to debian project, in the mean time I maintain some packages on my side.
I maintain two repositories:
Be sure to understand what your doing.
You might set the default release for apt if you intend to mix:
# /etc/apt/apt.conf APT::Default-Release "testing"; # for instance
Then add some pinning to prevent from upgrading/installing automatically:
# /etc/apt/preferences.d/kaliko Package: Pin: release o=kaliko.me Pin-Priority: 100
release file are digitally signed.
A package is available to include the key to apt keyring.
Or you might add gpg key manually: firstname.lastname@example.org 0x065FE53932DC551D gpg.
Or from a key server:
apt-key --keyring /etc/apt/trusted.gpg.d/kaliko.me.gpg adv --recv-key 0x065FE53932DC551D
Add source list, for instance in /etc/apt/sources.list.d/kaliko.list:
# /etc/apt/sources.list.d/kaliko.list deb http://deb.kaliko.me/debian/ testing main deb-src http://deb.kaliko.me/debian/ testing main