Debian developer Mike Gabriel in cooperation with the UBports developers continuing to maintain Ubuntu Touch and Unity 8 are working to offer Unity 8 (and in turn, Mir) packages within Debian.

With the Unity 8 desktop support being revived ahead and with Debian having no good desktop environment for Debian on tablets, Unity 8 and Mir packaging is being prepared for upstream Debian. This in turn will also help Debian derivatives wanting to offer Unity 8 as an option in the future.

Unity 8 requires Mir for acting as the (now Wayland-based) compositor.

More detains on this packaging work of Unity 8 and Mir for Debian can be found via Mike Gabriel's blog.