Mir 2.28.1 hits the release-candidate stage with practically no code changes
Canonical's Mir compositor library has begun freezing its next maintenance release, and the candidate that arrived with it is about as plain as a software tag gets.
Today, Mir v2.28.1-rc has been tagged. The mir-ci-bot, which signs its tags with a verified PGP key, ran a version bump and declared the build a candidate. This is a point release sitting on top of Mir 2.28.0, which shipped back in June. No new features. No bugfixes. No protocol changes. The whole distance between the two is three commits across six files.
Keep in mind that this is exactly what a patch-release candidate should look like. Testers get a frozen, effectively-final build to hammer on, and the -rc suffix holds until something forces another round.
What the release actually contains
Look at the commit history and the story is obvious. The first patch, b60d9bc, updated the repo for Ubuntu Linux 26.10. The second, 20f226d, limited CI on the release/2.28 branch to Ubuntu 24.04 so nobody spends test cycles on targets outside the supported set. The third commit is just the tagging bump.
That final one touched packaging files only. Ten lines added, two removed. CMakeLists.txt got a new version number, debian/changelog picked up an UNRELEASED entry, and the RPM spec gained a -rc suffix. That's the entire delta.
ABI-wise, nothing moved. If you link Mir libraries and are tracking from 2.28.0 to 2.28.1, nothing needs recompiling. miral stays at level 7. mirserver holds at 67. Both unchanged, and neither broken.
What Mir is (and why this matters)
If you're wondering why a point release of a compositor library warrants coverage, the answer lies in what Mir actually is. Canonical describes it on GitHub as "C++ libraries for writing Wayland Shells." Put more plainly, Mir is a toolkit for building the part of a system that talks to your GPU, composites windows onto a screen, and decides how they behave. It isn't a desktop itself. It's the engine that other desktops run on.
It's hard to remember now, but Mir was once pitched as the future of Ubuntu's own desktop. The idea was a single OS that morphed between a phone and a computer depending on which you were holding. That convergence dream quietly dissolved in 2017, when Canonical switched to GNOME for its desktop. Mir didn't die. It just got turned toward kiosks, point-of-sale terminals, and IoT hardware, where it has quietly thrived ever since.
The substance of this maintenance line actually comes from Mir 2.28.0. That release brought real additions, including server-side window-decoration support for KDE, external EGL texture rendering for libhybris-based stacks, a way to pin compositing to a specific graphics provider, and the first real steps toward a Rust-based Wayland frontend. Alongside that were the usual correctness fixes: thread-safe time conversion, an Xwayland hardening that dropped the insecure tmpnam call, and several memory-leak repairs.
Canonical's Mark Shuttleworth framed Mir's post-GNOME purpose plainly back in 2017. "We have lots of IoT projects using Mir as a compositor so that code continues to receive investment," he said. If the downstream has grown since, that bet looks reasonable.
The ecosystem is where Mir earns its keep. Ubuntu Frame, Canonical's own fullscreen kiosk shell, leans on it, as does the independent Miracle-WM and the Lomiri desktop that grew out of Unity 8. LXQt has crossed over onto Mir across several distros, and Ubuntu Touch still runs Unity 8 natively on it.
That last point is worth lingering on. In a Linux display world that increasingly looks like an Xorg-to-Wayland one-liner, Mir remains one of the few compositor libraries shipping a stable, versioned C++ ABI with a genuine security and embedding focus. It's arguably overkill for most people's laptops. It's exactly right for a kiosk that has to keep running on 24.04 for the next decade.
Head here to the PPA if you want to test it yourself:
sudo add-apt-repository ppa:mir-team/rc sudo apt update
The ppa:mir-team/rc holds current candidates across supported Ubuntu series, while the ubuntu-frame snap's 24/candidate channel tracks the release for embedded use. U
Head here to the GitHub release page.
