really basic polybar setup

nixos/i3/default.nix

@@ -181,12 +181,17 @@
 
         bindsym $mod+r mode "resize"
 
-        # Start i3bar to display a workspace bar (plus the system information i3status
-        # finds out, if available)
-        bar {
-          status_command ${pkgs.i3status}/bin/i3status
-          position top
-        }
+        exec_always --no-startup-id ${
+          pkgs.writeShellScriptBin "launch-polybar.sh" ''
+            # note: all polybar configs have to have IPC enabled in order for
+            # this to work!
+            ${pkgs.polybarFull}/bin/polybar-msg cmd quit
+
+            ${pkgs.polybarFull}/bin/polybar --config=${
+              ./polybar.ini
+            } top 2>&1 | tee -a /tmp/polybar-top.log & disown
+          ''
+        }/bin/launch-polybar.sh
 
         # Automatically send things to the right workspaces
         assign [class="browser"] 2

nixos/i3/polybar.ini

@@ -0,0 +1,47 @@
+[bar/top]
+enable-ipc = true
+
+modules-left = i3
+modules-right = cpu battery backlight date
+
+[module/backlight]
+type = internal/backlight
+card = intel_backlight
+
+format = <ramp>
+; TODO: need a font that supports emoji
+ramp-0 = 🌕
+ramp-1 = 🌔
+ramp-2 = 🌓
+ramp-3 = 🌒
+ramp-4 = 🌑
+
+[module/battery]
+type = internal/battery
+full-at = 89
+; see formatting options at https://github.com/polybar/polybar/wiki/Module:-battery
+
+[module/cpu]
+type = internal/cpu
+
+format = <label> <ramp-coreload>
+label = CPU %percentage%%
+
+; Spacing between individual per-core ramps
+ramp-coreload-spacing = 1
+ramp-coreload-0 = ▁
+ramp-coreload-1 = ▂
+ramp-coreload-2 = ▃
+ramp-coreload-3 = ▄
+ramp-coreload-4 = ▅
+ramp-coreload-5 = ▆
+ramp-coreload-6 = ▇
+ramp-coreload-7 = █
+[module/date]
+type = internal/date
+date = %A, %B %d, %Y%
+time = %I:%M %p%
+label = %date% %time%
+
+[module/i3]
+type = internal/i3