Other systems

There are two ways to run it on a system without a package: the display manager from the release archive, or only the greeter, under greetd.

The display manager from the archive

The release's lys-login-<version>-<arch>-linux.tar.gz (x86_64 or aarch64) holds the files the packages install, with both distributions' PAM services under pam/. The binary asks for the standard program interpreter, and the unit names /usr/bin/lys-login and /usr/bin/lys-wm; lys-wm has an archive of its own in its releases. From the unpacked directory:

sudo install -m 0755 lys-login /usr/bin/lys-login
sudo install -m 0644 lys-login.service /usr/lib/systemd/system/
sudo install -D -m 0644 lys-login.sysusers /usr/lib/sysusers.d/lys-login.conf
sudo install -D -m 0644 lys-login.tmpfiles /usr/lib/tmpfiles.d/lys-login.conf
sudo systemd-sysusers lys-login.conf
sudo systemd-tmpfiles --create lys-login.conf
sudo systemctl daemon-reload

Then write /etc/pam.d/lys-login for your distribution from the file under pam/ closest to it (PAM services), and switch display managers:

sudo systemctl disable gdm
sudo systemctl enable lys-login

The greeter under greetd

Point greetd's default_session at the greeter, hosted by cage:

# /etc/greetd/config.toml
[default_session]
command = "cage -s -- lys-login greet --config /etc/lys-shell/config.yaml --state /var/lib/lys-greeter/last-session"
user = "greeter"

greetd starts the kiosk compositor, whose single client is the greeter, and replaces it with your chosen session on login:

greetd → cage -s → lys-login greet → (login) → your compositor

• The greeter runs as the greetd user with no usable home, so its config lives at a system path, /etc/lys-shell/config.yaml by default.
• Create the state directory, writable by the greetd user: install -d -o greeter -g greeter -m 0700 /var/lib/lys-greeter.
• Sessions come from /usr/local/share/wayland-sessions and /usr/share/wayland-sessions, and the same for xsessions. --sessions DIR and --xsessions DIR override them.
• Append an explicit fallback session with -- sway. It is offered as "Custom", and is the only entry when there are no session files.

Under greetd there is no daemon, so lys-login record-cursor has nothing to talk to and apply-config needs root. See Configuration.

home-manager

lys-login.homeManagerModules.default with programs.lys-login.greeter.enable installs cage and a lys-greeter-session wrapper, cage and the greeter in one command, to point greetd at. It passes its arguments on to lys-login greet:

lys-greeter-session --config /etc/lys-shell/config.yaml --state /var/lib/lys-greeter/last-session

home-manager cannot manage greetd or PAM, so the module warns with what is left to do. Its greeter.settings go to $XDG_CONFIG_HOME/lys-shell/greeter.yaml; copy them somewhere the greetd user can read. programs.lys-login.enable alone installs the binary for the lock screen.

Rendering without a GPU

The login screen needs no GPU: it draws on the CPU when Vulkan is not available. LYS_UI_RENDERER=cpu forces that. For cage, set WLR_RENDERER=pixman and WLR_DRM_NO_MODIFIERS=1. The home-manager wrapper sets all three with greeter.renderer = "software". This suits VMs and hosts where GPU setup is unreliable.

On a host that is not NixOS, the nix-built package needs nixGL around the whole launch for the GPU:

nixGLIntel lys-greeter-session --config /etc/lys-shell/config.yaml --state /var/lib/lys-greeter/last-session