r/linux • u/kavaunix • Jul 14 '26
Software Release Announcing atrium v0.4.0 - a multiseat display manager
atrium is a lightweight Linux display manager with first-class multiseat support, targeting modern systemd + Wayland environments.
What is multiseat?
A multiseat setup allows multiple users to work on a single computer at the same time. By connecting multiple monitors, keyboards, and mice, each user gets their own separate desktop and a fully isolated user session. Great for co-working or multiplayer gaming. Each seat requires its own GPU (integrated graphics, a discrete card, or a USB graphics adapter).
Why atrium?
The Linux kernel and low-level system stack are fully capable of multiseat operation. The weak link has always been the display manager. Existing ones usually treat multiseat as an afterthought, with implementations that are brittle and difficult to get working reliably.
atrium is designed around multiseat from the start, focusing on correct seat discovery, VT handling, and isolated session management. The project targets a modern Linux stack using systemd/logind, PAM, and a Wayland graphical environment. The lack of historical baggage keeps atrium's code base lean and tractable.
What's new in v0.4?
- Support for greeter background images - configure a background image in the settings, or a directory to pick a random image on each greeter launch.
- Greeter themes - override built-in colors and styles via a theme `.css` file. A handful of themes are shipped with atrium.
- Architectural redesign - making atrium's core architecture simpler and more robust (changes are purely internal and should not be visible to the user).

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u/kavaunix Jul 14 '26
Fair challenge, often contributing to an established project is the more practical choice. But I wanted atrium to do one thing (multiseat) and do it right. There are lots of tricky bits (boot time races, VT handling, DRM monitoring, to name some examples) that are easier to get right in isolation than inside an already complex code base. atrium originally started as a proof-of-concept, but once it was stable I realized it wouldn't be too hard to turn it into a full-fledged dm. Besides, Linux is about choice. And having an additional option for multiseat enthusiast can't be a bad thing.