Install niri (Wayland WM/compositor) using Nix package manager on any Linux distribution

General information

niri – a scrollable-tiling Wayland compositor
https://github.com/YaLTeR/niri/

Nix wiki
https://wiki.nixos.org/wiki/Nix_package_manager
https://wiki.nixos.org/wiki/Nixpkgs

Nixpkgs search – the Nix Packages collection
https://search.nixos.org/packages

Set up nixpkgs environment

$ yourpkgmgr install nix    # or nix-bin, or similar

$ gpasswd -a yourusername nix-users
$ exit
$ systemctl enable --now nix-daemon.service

$ nix-channel --add https://nixos.org/channels/nixpkgs-unstable
$ nix-channel --update
$ nix-env --install --attr nix-bash-completions

nixpkgs-unstable channel corresponds to the main development branch (unstable) of Nixpkgs, delivering the latest tested updates on a rolling basis.

~/.profile

#export NIX_PATH="$HOME/.nix-defexpr/channels"
PATH="$HOME/.nix-profile/bin:$PATH"
XDG_DATA_DIRS="$HOME/.nix-profile/share:$XDG_DATA_DIRS"

~/.config/systemd/user.conf

[Manager]
ManagerEnvironment="XDG_DATA_DIRS=%h/.nix-profile/share:/usr/local/share:/usr/share"

$ systemctl --user daemon-reload

Install niri and other components

$ nix-env -iA niri

$ nix-env -iA mesa
$ nix-env -iA xwayland-satellite
$ nix-env -iA waybar
$ nix-env -iA alacritty
$ nix-env -iA fuzzel

Complete list of recommended packages to install

$ nix-env --query
alacritty-0.15.1
brightnessctl-0.5.1
font-awesome-6.7.2
fuzzel-1.11.1
gammastep-2.0.9
mako-1.10.0
mesa-25.0.3
niri-25.02
swaybg-1.2.1
swayidle-1.8.0
waybar-0.12.0
waypaper-2.5
xwayland-satellite-0.5.1

Install NixGL wrapper

$ nix-channel --add https://github.com/nix-community/nixGL/archive/main.tar.gz nixgl
$ nix-channel --update nixgl
$ nix-env -iA nixgl.auto.nixGLDefault

Make fonts from nixpkgs available

$ mkdir -p ~/.local/share/fonts
$ ln -s ~/.nix-profile/share/fonts ~/.local/share/fonts/nix-fonts

Launch niri

from Console

$ nixGL niri-session

from Login Manager

$ cp ~/.nix-profile/share/wayland-sessions/niri.desktop /usr/share/wayland-sessions/niri-nix.desktop

/usr/share/wayland-sessions/niri-nix.desktop

Exec=nixGL niri-session

Customize configuration of individual tools

$ cp -r ~/.nix-profile/etc/xdg/waybar ~/.config/
$ cp -r ~/.nix-profile/etc/xdg/fuzzel ~/.config/

Keep all packages up-to-date

$ nix-channel --update
$ nix-env --upgrade

Try to fix failure to launch or black screen after Mesa updates

$ nix-env -iA nixpkgs.mesa

and then

$ nix-env -iA nixgl.auto.nixGLDefault

If all else fails, roll back generations.

$ nix-env --list-generations
$ nix-env --rollback

Repeat until working state has been restored.

Clean up

Perform only when everything works properly. After this, rollback is not possible.

$ nix-collect-garbage --delete-old