Xephyr is an X-on-X implementation and runs on X.Org Server and can work with Glamor.

[citation needed] Replacing Xephyr with the xf86-video-dummy and xf86-video-nested drivers in the normal X.Org server is being considered as part of X11R7.8.

[2] Unlike the similar Xnest, Xephyr supports modern X extensions (even if the host server does not) such as composite, damage, and randr.

It uses SHM images and shadow framebuffer updates to provide good performance.

Xorg's version of Xephyr uses only software rendering for OpenGL, but Feng Haitao has developed a forked version of Xephyr which can do hardware-accelerated rendering if the underlying X server has the capability.