without installing another distro over the top of it ... [replace] package managers

The package manager is the distro, though.

$ pacman -S apk-tools
$ apk add alpine-base linux-lts

Then kexec to alpine's kernel and the initramfs generated by its installation (which would incidentally "replace" PID 1 with the new /sbin/init). For clean up you could take a diff of "tar -t" for all the installed packages from both distros then delete the files only in the old distro's packages.

Make a self-compiled distro your target.

Replace the first step with a compilation of apk, abuild everything required by alpine-base and linux-lts (git clone aports to bootstrap that work), then add the package directory to /etc/apk/repositories before the second step. Next, begin to worry that you haven't fully broken free yet, replace abuild with a bespoke mybuild and apk with tar -x, grapple with signed binaries, reflect on your own identity and authenticity, then take a tour through gentoo and find yourself missing the $HOME you left and its familiar comforts.

Okay i'll cheat with Guix then

May, I introduce you to bedrock

This is what I was doing with my server. I've learned there's no better feeling than starting from scratch.

Love the idea of the challenge, my issue would be lack of a validator tool to confirm I'd completed the challenge - any suggestions?

Ummm you go first.

Theoretically one could also prohibit rebooting.

IIRC kexec is pivot_root but for the kernel.

The compiled distros should be easy instead of nightmare tbh

kid named nixos-infect:

I would watch a YouTube series doing this

So, any distro to any other distro?

• Installs Fedora Silverblue
• Rebases to Bazzite

Jobs done chief!

Hell: from macOS to WSL.

New Game+: speedrun it

I "broke" linux mint just by trying to pop KDE on, had to timeshift because it messed up my keyboard layout and a whole bunch of other things with my display.

I don't know how people do these crazy changes without pain, and have a feeling the answer is simply "there's pain" 😂

Reminds me of a recent post someone converted their system from Debian to OpenBSD via SSH only

“Medium: Same as easy but go from the derivative to the base.”

I can't quite recall, but I think I did exactly that with Ubuntu -> Debian once upon a time. I think Ubuntu was only a year or so old though, so there wasn't a huge amount of divergence back then. As a bonus anecdote I also attempted a semi-successful build of Gentoo on a PPC Mac around the same time (nothing before or after that has compared in its level of nightmare).

I have seen dozens of systems migrated from Gentoo to CentOS by live swapping the userspace and eventually rebooting into the new kernel. A hair raising experience to be sure.

To add sadism on top of masochism, tell all your friends how you did it in great detail

I think it would be very interesting to convert e.g. a regular Fedora installation into a (so-called “immutable”) Fedora Silverblue installation or vice-versa.

I once switched from Debian i386 to amd64 in-place. That was MUCH harder than you would expect, I guess somewhere between medium and hard in your list. That server is still running that install btw, so in the end it all worked out.

debootstrap makes this easy, and familiarity with that process introduces chroot skills.

Shouldn't everyone that installed Arch the right way be able to do it on most distros, simply after installing Pacman?

Though I think changing (shrink, create new, migrate, delete old) the partition layout would count as installing another distro on top...

Want a challange? Start with something like Silverblue.

It is quite easy to go slackware -> gentoo from what I remember but minimalist distros might be cheating

Linux From Scratch rulez!

Migrate from Nix to Linux From Scratch!

Is that even possible? I'm already in panic when I remove a package and it's dependencies with pacman 😅.

Sure I did replaced Thunar with Nemo, but a few things don't work exactly how it should, like opening the download directory from Firefox (Known issue BTW) even though all mime-types are correctly set !

Even switching from Alternative -> Base distro seems like a really difficult task :/

I am not educated enough about this, but don't these kind of games unnecesarrily strain all the servers that host the packages for people that really need them for download and most of these people run these servers for free in good will and faith that they will serve meaningful needs with positive impact? I am sorry for spoiling the fun, but I felt like I had to point this out.