Unattended updates in Debian

Because Debian is really stable and has high security patching standards, you should have auto-upgrades on if you are running stable. This is one of the things that you cannot have with more bleeding edge distros like ArchLinux.

Read through official docs in order to set it up now.

TLDR:

$ sudo apt-get install unattended-upgrades
$ sudo dpkg-reconfigure -plow unattended-upgrades
$ echo 'APT::Periodic::Enable "1";
APT::Periodic::Update-Package-Lists "1";
APT::Periodic::Download-Upgradeable-Packages "1";
APT::Periodic::Unattended-Upgrade "1";
APT::Periodic::AutocleanInterval "21";
APT::Periodic::Verbose "2";' | sudo tee /etc/apt/apt.conf.d/02periodic

And then to ensure that things are configured somewhat well:

$ sudo unattended-upgrade -d