Mir 0.4 Released, Mir 0.5 Under Development
Canonical's Mir display server for Ubuntu Linux has cleared Mir 0.4.0 for Ubuntu 14.10 "Utopic" while Mir 0.5 is immediately under development.
Mir 0.3 was released just a few weeks ago while Canonical developers are already out with the latest release. Mir 0.4.0 brings several new features including a surface attribute for visibility, a surface orientation API, and a number of changes to the Mir Server code. Both the Mir client and server ABIs were bumped by v0.4.0. More details on the 0.4 release can be found via Mir on Launchpad.