magnetar

Magnetar

mag·ne·tar /ˈmæɡ.nɪ.tɑːr/ noun

  1. A neutron star whose magnetic field is a thousand trillion times Earth’s.
  2. A Linux distribution built on Arch and CachyOS, with the COSMIC desktop and a suite of apps made for it.

Get MagnetarBrowse the source ↗

The live field needs JavaScript, so this is a still image.

Field

Charged particles sliding along a tilted dipole, jets sweeping like a pulsar.

Spin period
—
Axis tilt
—
Field particles
—
Renderer
starting

What it is

A distribution built like the star it’s named after

A neutron star has a dense core, a thin crust, and a magnetosphere that reaches far past both. Magnetar is built the same way: a rolling Arch Linux system with CachyOS’s kernel and packages at its core, the COSMIC desktop over it, and its own applications around the outside.

Cross-section of a neutron star: an Arch Linux and CachyOS core, a COSMIC crust, and eight coloured field lines for the applications. core · Arch + CachyOScrust · COSMICmagnetosphere · the suite
MagnetosphereThe suite
Mail, calendar, contacts, passwords, a launcher and more, written in Rust for COSMIC and wired into the system. Locket is the keyring, Jump opens on Super+Space, and Envelope hands meeting invitations to Slate.
CrustCOSMIC
System76’s Rust desktop on Wayland, set up from the first boot: the COSMIC greeter, PipeWire audio, Qt apps themed to match, Ghostty as the terminal, and firmware updates through fwupd.
CoreArch & CachyOS
Arch Linux’s rolling base and pacman, with CachyOS’s kernel, hardware detection and packages rebuilt for x86‑64‑v3, v4 and Zen 4. Magnetar follows both upstreams rather than forking them, so their fixes reach you as they ship.

The magnetosphere

Applications that exist nowhere else

Each one is held to the best app in its category, feature for feature. Point at one and its line lights up in the field.

Underneath and alongside

How it’s made

The brief every app is built against

Measured in September 2026

~223,000 lines of Rust3,085 tests0 todo!() callsApps GPL‑3.0, substrate MPL‑2.0

Get Magnetar

Two ways in

Pre-release. The live ISO is not published yet, and the package repository is still being filled.

From the live ISO

Boot into a live COSMIC session, try it, then install with the Calamares installer. Hardware detection sets up the drivers for your graphics card, NVIDIA included.

Base
Arch Linux, rolling release
Kernel
linux-cachyos, LTS available
Desktop
COSMIC on Wayland
Installer
Calamares
Packages
pacman, signed [magnetar] repository
Filesystems
ZFS kernels available

Already running CachyOS? Switch over

  1. Trust the signing key

    Import the key pacman will check every package against, then confirm the fingerprint before you sign it.

    curl -sLo /tmp/magnetar.asc https://repo.magnetaros.com/magnetar.asc
sudo pacman-key --add /tmp/magnetar.asc
sudo pacman-key --lsign-key 382D984841F8C8A2BFB952675623FAF3DF36FFAF

    Fingerprint 382D 9848 41F8 C8A2 BFB9 5267 5623 FAF3 DF36 FFAF, Magnetar OS (package signing) <packages@magnetaros.com>

  2. Add the repository

    Add this to /etc/pacman.conf, above the [cachyos] section: pacman takes each package from the first repository that has it. Keep the signature level as written.

    [magnetar]
SigLevel = Required DatabaseOptional
Server = https://repo.magnetaros.com/$arch

  3. Install Magnetar

    One meta package brings in the COSMIC desktop and Magnetar’s defaults and branding. The apps are packages of their own, so drop any you don’t want from the last line.

    sudo pacman -Syu
sudo pacman -S magnetar-desktop
sudo pacman -S slate envelope circle locket jump magnetar-peek magnetar-pencil pocket