Trying out niri

I have been using sway for a while. sway is good. I can remember only one bug where chromium was able to trigger assertion failures and compositor crashed on huge 32K-wide surfaces. It was a bug in wlroots which was fixed quickly.

I occasionally look around for other compositors that I could use to check out slightly different tiling ideas and fancy features of a modern wayland desktop. This time I tried niri. It looked quite close to sway, uses rust as implementation language and kdl as a config language.

I turned niri to match my sway config very quickly.

niri Config Tweaks

I switched Alt as a primary Mod key to keep window dragging via Alt+<drag> instead of Super+<drag> (niri calls Mod4 a Super):

input {
    // Alt to allow for Alt-drag for floating windows.
    mod-key "Alt"
    mod-key-nested "Super"
}

I disabled all animations to get UI to react faster:

animations {
    off
}

I created named workspaces to simulate static workspaces (I did the same in sway, neither compositor considers it a preferred mode):

workspace "1: any"
workspace "2: irc"
workspace "3: jabber"
workspace "4: any"
workspace "5: liferea"
workspace "6: web"
workspace "7: mail"
workspace "8: net"
workspace "9: music"

binds {
    Control+F1 { focus-workspace "1: any"; }
    Control+F2 { focus-workspace "2: irc"; }
    Control+F3 { focus-workspace "3: jabber"; }
    Control+F4 { focus-workspace "4: any"; }
    Control+F5 { focus-workspace "5: liferea"; }
    Control+F6 { focus-workspace "6: web"; }
    Control+F7 { focus-workspace "7: mail"; }
    Control+F8 { focus-workspace "8: net"; }
    Control+F9 { focus-workspace "9: music"; }
    Ctrl+Shift+F1 { move-column-to-workspace "1: any"; }
    Ctrl+Shift+F2 { move-column-to-workspace "2: irc"; }
    Ctrl+Shift+F3 { move-column-to-workspace "3: jabber"; }
    Ctrl+Shift+F4 { move-column-to-workspace "4: any"; }
    Ctrl+Shift+F5 { move-column-to-workspace "5: liferea"; }
    Ctrl+Shift+F6 { move-column-to-workspace "6: web"; }
    Ctrl+Shift+F7 { move-column-to-workspace "7: mail"; }
    Ctrl+Shift+F8 { move-column-to-workspace "8: net"; }
    Ctrl+Shift+F9 { move-column-to-workspace "9: music"; }
}

I disabled client side decorations:

prefer-no-csd

The whole config hides here.

waybar Tweaks

waybar changes looked even smaller. I mimicked sway plugins:

--- a/.config/waybar/config
+++ b/.config/waybar/config
@@ -3,19 +3,25 @@
     "spacing": 10, // Gaps between modules (4px)

     "modules-left": [
+        "niri/workspaces",
         "sway/workspaces",
         "sway/mode",
         "sway/scratchpad"
     ],
     "modules-center": [
+        "niri/window",
         "sway/window"
     ],
     "modules-right": [
         "idle_inhibitor",
+        "niri/language",
         "sway/language",
         "custom/upgrade-status",
     ],

+    "niri/mode": {
+        "format": "<span style=\"italic\">{}</span>"
+    },
     "sway/mode": {
         "format": "<span style=\"italic\">{}</span>"
     },

Niceties

I’m using niri for a month as my main compositor on the desktop.

Less Window Resize

I was pleasantly surprised to see that windows flicker even less now: niri does not resize existing windows and moves them around instead. I suspect it causes less redraws to existing apps. Such resizes was a big stopper for me when I tried hyprland.

Cursor Removal on Timeout and on Typing

niri has a way to hide mouse cursor after a timeout:

cursor {
    hide-when-typing
    hide-after-inactive-ms 1000
}

I use cursors of ridiculous size. I did not know I needed this feature!

Monitor Power off Action

On sway I used to send signal to swayidle to shut off monitors on a key binding. In niri there is a special power-off-monitors action for that:

binds {
    Scroll_Lock { power-off-monitors; }
}

Print Screen Built-In

Similar for screenshots. There is quite the selection of various shots:

    Print { screenshot; }
    Ctrl+Print { screenshot-screen; }
    Alt+Print { screenshot-window; }

Snags and Problems

I did not encounter any major problems but found a few quirks and missing bits.

Running Nested niri Breaks Key Bindings

On a default config you can run niri as a regular window application. To distinguish where hotkeys should be handled (host vs windowed) niri provides input.mod-key / input.mod-key-nested configuration. But I use too many hotkeys and effectively use both Mod key variants for various keys. As a result when nested niri is started it seems to do something to my host niri and some keys stop working. I need to debug it in more detail. It feels like an easily fixable problem.

No Taskbar View by Default

On sway I could see all the windows on the workspace by looking at the window top. niri does not provide that by default. I did not find a substitute yet. Rumors say I could write a waybar plugin.

Fun Effects

niri uses slightly different approach to XWayland startup than sway. I decided not to configure it at all to see what I’m using X11 for still. And I realized the only application that was still trying to probe X11 was chromium. I had to add --ozone-platform=wayland to my browser startup script to get it to start in X11-less environment.

I very occasionally run xwayland-satellite to get one-off things to run.

Parting Words

niri is surprisingly nice! For me it was very easy to switch from sway as both expose similar concepts through configuration. I like kdl as a configuration language and am glad to see more and more projects use it.

niri does not resize existing windows (I don’t use splits that frequently), but moves them around instead. It looks like this alone reduces application flicker when they have to resize and reach by updating UI.

Have fun!