Maybe don't write an Xorg window manager right as the replacemeant for Xorg starts to take off though

This is exactly why I would rather do. I see absolutely no reason to abandon X and want to learn its internals to be able to maintain it myself. To me X seems a perfect piece of software which just works and does its job flawlessly, while having all the features I ever needed (including remote execution - I used Windows apps running on a remote Linux machine with Wine over SSH over OpenVPN on a local Windows machine and that was very easy).

1. Wayland does support remote execution; see waypipe for an example.

2. X11 does lack critical features that lots of users need: GUI isolation (a very basic security measure that's otherwise been standard practice for decades), mixed DPIs, and perf on low-end ARM devices (compare Sway with dwm/openbox/i3 on a rbpi or pinebook and the difference is kinda shocking).

X worked just fine on early 90s hardware. Performance today is about implementation, nothing inherent about X.

ARM chips did not exist in the early 90s, and compositors weren't the norm either. Current integrated graphics processors are optimized for a very different landscape. A typical X setup also includes a compositor to mitigate screen tearing.

Factor all this into account and I'd be interested in seeing an X setup without screen tearing that performs at least as well as Sway on a Pinebook or a rbpi.

What are, if any, use cases where one would need a compositor? Other than transparent window decorations, wobbling windows and overlay dock? These are kinda cool but not worth any additional complexity or hardware resources IMHO.

I have never seen any screen tearing in my life by the way. Despite I have always been generally using decade-old PCs with lowest-end (mostly built-in) GPUs and Raspberry Pi is the only way I watch TV. The only annoyance I have with Raspberry Pi is YouTube the website (not the actual video, it plays Ok) being rather slow.

Have you tried playing a video? Or moving a window around fast? Without a compositor there will be tearing on X. With a compositor, X is just a useless middleman.

There's nothing stopping an X server implementation from doing compositing natively.

Other than writing an X server implementation is akin to writing a web browser from scratch?

There's absolutely no reason to write an X server from scratch to add native compositing support.

You're also massively overstating the complexity of an X server. Writing X servers that are advanced enough to be usable is something a lot of individuals have done. It's nothing like matching a modern browser. Incidentally, if I were to try to do this today, I'd gut a proxy like Xephyr and make it rootless to support older clients, and make the main server itself only support the subset of the X protocol modern clients speak.

> You're also massively overstating the complexity of an X server. Writing X servers that are advanced enough to be usable is something a lot of individuals have done.

If so, why are we observing apparent shortage of developers to maintain the actual Xorg? I can't believe there are no people interested in maintaining it in the whole world. I thought it's so complex it just requires much more expertise and dedication than anybody is ready to invest.

Because Xorg is a huge beast with plenty of legacy, and it's also not a very fun project to hack on because it's largely maintenance of stuff people only care about when it breaks.

E.g. support for a bunch of backends of which most are not worth supporting if you want to implement a server from scratch, but which Xorg has been saddled with, as well as support for a bunch of legacy X functionality that nobody would bother implementing if implementing a server from scratch because most clients never use it.

E.g. a major source of complexity is supporting various X visuals that are irrelevant today when you can decide to only support truecolor natively. Another is support for a bunch of drawing primitives that you might as well just ditch all but the very simplest of, and support for legacy clients via a proxy like Xephyr. That said, most of those drawing primitives are also supported by any 2d canvas style library like Cairo or Skia that does client side 2d rendering, so if you want to implement them for an X server, just picking up one of those libraries would be time far better spent than implementing it yourself.

It'd certainly be a lot of work, and a lot more work to write an X server from scratch that is a complete replacement for e.g. Xorg - you'd need to support a number of X protocol extensions, but most clients backends will fall back on core functionality if extensions are not available (you'd definitely want to support some of them, like Xrender and SHM though, or your server would be largely unusable with modern clients).

At the same time, if someone wants to write a new X server, it'd be silly to do the work of writing their own backends when the could just grab wlroots and build an X server on top of that. "Modern X11" can be reduced to a relatively narrow superset of Wayland functionality if you defer most of the weirder legacy functionality that is rarely but very occasionally used to a proxy like XWayland, Xephyr or XPRA (all of which do, that said, rely on Xorg code) and make people use those for clients that need it.

Honestly, I think this is the most likely/viable future for X on Linux. It'd drastically reduce the amount of code to maintain and share that burden with other projects, and would make it far more viable to keep maintaining X support for those of us who wants (part of) it.

I really don't understand this line of thinking or what you are trying to accomplish. If you are dropping things from the X protocol to the point where it's only XInput2.2, SHM and DRI3, and then farming the rest out to Xephyr, then it's no longer X anymore. That is pretty much entirely what Wayland already is. So you might as well just build it as a Wayland server and call it a day.

I'm not doing this, it's a thought experiment. I'm happy to stay with X for a long time if necessary.

But what you list is not enough, though. There are enough extra bits that goes well beyond what Wayland provides today, like ability to write a standalone wm without having to build a whole compositor, for example, that you'd end up with something quite substantially unlike Wayland if you went down that route and looked at which pieces of X11+extensions people are actually using. It'd be far less than full on legacy X11, but far more than just Wayland.

It doesn't matter if it's not X. Nobody but extreme purists would care if it's not exactly X. What will matter is if you lose capabilities.

E.g currently my preferred wm (bspwm) doesn't have a Wayland alternative, so a Wayland compositor isn't a viable option for me without changing my workflow. Sway might be nice, but it's different and I have no compelling reason to put in the effort to make a switch until running Xorg starts becoming problematic. One day, maybe I'll feel compelled to switch but it won't be soon.

Even so, Xorg will hang around for decades in the form of XWayland because of old X apps people still use (e.g. none of the terminals I have installed on my system except for gnome-terminal supports Wayland).

I still see no purpose to do that, with a lot of hacking it would be also possible to make XWayland work with window managers. But that also would be pretty pointless to do because those other parts of the X protocol are also bad and need to be replaced, you might as well just rewrite the window manager.

If you liked bspwm then you might want to try this: https://github.com/riverwm/river

> If you liked bspwm then you might want to try this: https://github.com/riverwm/river

If I wanted to spend time redoing my configuration, maybe, but I have better things to spend my time on. So in however many years it takes before getting Xorg running starts taking more effort than switching. I'm not expecting that to happen anytime soon.