Since you’re installing Debian, presumably you’ve done the required reading according to their wiki, and seen the DontBreakDebian page.

If not, here’s the portion I’m thinking of (emphasis mine)

Don’t make a FrankenDebian

Debian Stable should not be combined with other releases carelessly. If you’re trying to install software that isn’t available in the current Debian Stable release, it’s not a good idea to add repositories for other Debian releases.

First of all, apt-get upgrade default behavior is to upgrade any installed package to the highest available version. If, for example, you configure the forky archive on a trixie system, APT will try to upgrade almost all packages to forky.

This can be mitigated by configuring apt pinning to give priority to packages from trixie.

However, even installing few packages from a “future” release can be risky. The problems might not happen right away, but the next time you install updates.

The reason things can break is because the software packaged for one Debian release is built to be compatible with the rest of the software for that release. For example, installing packages from forky on a trixie system could also install newer versions of core libraries including libc6. This results in a system that is not testing or stable but a broken mix of the two.

Repositories that can create a FrankenDebian if used with Debian Stable:

• Debian testing release (currently forky)
• Debian unstable release (also known as sid)
• Ubuntu, Mint or other derivative repositories are not compatible with Debian!
• **Ubuntu PPAs and other repositories created to distribute single applications **

Some third-party repositories might appear safe to use as they contain only packages that have no equivalent in Debian. However, there are no guarantees that any repository will not add more packages in future, leading to breakage.

Finally, packages in official Debian releases have gone through extensive testing, often for months, and only fit packages are allowed in a release. On the other hand, packages from external sources might alter files belonging to other packages, configure the system in unexpected ways, introduce vulnerabilities, cause licensing issues.

Once packages from unofficial sources are introduced in a system it can become difficult to pinpoint the cause of breakage especially if it happens after months.

I would personally add that this isn’t a case of “if”, but rather “when”. Even if it works at the beginning, all it takes is Mint deciding they want to use a newer library when they update the package you’re using, and suddenly your system won’t boot and there’s no clear, easy solution other than “restore from backup.”

Even if you know what you’re doing, I would limit tinkering to binaries managed in the $HOME/.local/bin (and any applications that work as package management for that, like cargo, pip or homebrew) or packages that you completely control yourself (such as through git pulls and compiling yourself).

“Stick to the official repo” is generally the advice I would give for any distro, with the exception of DIY OSes that are intended to be patchwork, like gentoo or Arch.

THAT BEING SAID: I’m not saying “don’t install without a DE and piece your desired DE together from their parts.” Debian has a lot of DEs, window managers, and their individual parts all in the official repos; a lot of the difference you see between the versions Debian offers and the versions Mint or Ubuntu offer are basically just theming that you can do yourself without altering the system packages.

If you absolutely must install a 3rd party repo, just understand you are sacrificing Debian’s selling point of stability, and waiving your rights to hold the Debian Maintainers responsible; and when your system breaks (which might not be for many years), it will be entirely your own fault.

Debian strongly recommends against adding repos from other distributions or other versions of Debian: https://wiki.debian.org/DontBreakDebian#Don.27t_make_a_FrankenDebian Doing that can easily break your system. They also recommend against adding repos for specific software packages (e.g. for LibreWolf), but this is generally less problematic.

Personally, on Debian, I try to get packages in this order:

1. From the official Debian packages
2. From Flatpak
3. Pre-built binaries (I put them in my home, not in /usr/bin)
4. Build from source (I also put those in my home)

Is this hard to find because it’s something that people who don’t know what they’re doing shouldn’t mess with? Am i just looking in the wrong places, or for the wrong thing?

Yes! Third party repositories are a good choice when they add specific software not present in the distros repo like mullvad, icewolf or (and this is approaching an edge case but I’m a big fan of it at the moment) nvidia.

Third party repositories are a really bad choice when they cause conflicts with the distros repositories like adding Ubuntu’s main branch to any Debian in order to get a specific package.

For xed, the editor you’re asking about, the git page describes Debian appropriate build instructions.

You could always just use pluma, the editor xed forked from, which is in the Debian repositories.

E: also stop planning and jump in. You’re not gonna figure anything out from analyzing and planning, just try what you want and solve the problems you come across.

Typically the project will offer its own deb repos and packages along with setup instructions such as steam or docker

In theory you can add LMDE or other debian based distros repos to your sources but it will most likely lead to things breaking. If you cant find instructions specific to debian then you are better off either compiling from source or using snap, appimage or whatever pre-compiled option is offered officially.

If you’re going to add Mint repos anyway, why not just use LMDE or Mint instead of Debian? It probably would avoid strange version mismatch issues.

I’m on mint, these are my package mirrors (based in the Netherlands):

/etc/apt/sources.list.d/official-package-repositories.list

deb https://mirrors.evoluso.com/linuxmint-packages/linuxmint-packages zara main upstream import backport 

deb http://ftp.snt.utwente.nl/pub/os/linux/ubuntu noble main restricted universe multiverse
deb http://ftp.snt.utwente.nl/pub/os/linux/ubuntu noble-updates main restricted universe multiverse
deb http://ftp.snt.utwente.nl/pub/os/linux/ubuntu noble-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu/ noble-security main restricted universe multiverse

afaik there’s no public list of package mirrors