OBS can capture wlroots based compositors with the wlrobs[0] plugin. Give it a shot, it's really smooth for me. There's also wl-recorder[1] which is much more light weight if you don't need any of the fancier features. Also, cyanreg is working on txproto[2] which is a much faster/feature rich version of wl-recorder, although I'm not sure it is ready for prime time as it uses a couple bleeding edge libs.