I'm wondering if this backport method would work let's say if I'm trying to download Steam or Wine?
Like, once I have the backported package downloaded, would it stay up to date every time I 'apt update / apt upgrade'?
echo deb http://deb.debian.org/debian stretch-backports main | sudo tee /etc/apt/sources.list.d/stretch-backports.list sudo apt update
then you can install backported packages by adding
-t stretch-backports to your
apt invocation, or selecting the appropriate version in Synaptic.
It’s safe to leave the repository permanently enabled: it is never used for package installations if it’s not explicitly selected, but if a backported package is updated, it will automatically be selected for upgrade.
Note that the rules for backports mean that a backported package must always be older than the first version made available in the next stable release, so backports for Debian 9 (Stretch) will stop being upgraded once Debian 10 (Buster) is released. Backported packages can then be added to the sloppy repository, but that’s unusual.
When you upgrade from Debian 9 to Debian 10, any backported packages which you had installed in Debian 9 will be upgraded to their Debian 10 version (unless they have been dropped from the distribution).