There is intersting things going on to provide that. Wlroots landed wlr_scene api to make it much easier to create a compositor on top of wlroots. There is also

There is intersting things going on to provide that. Wlroots landed wlr_scene api to make it much easier to create a compositor on top of wlroots. There is also riverwm which is quite interesting, built as a tiling wm but delegating wm management to an app, so allowing to create any quite of window management on it.