try out i3 config from: https://github.com/jifuwater/Cattendeavou

modules/graphical/i3.nix

@@ -0,0 +1,52 @@
+{ config, pkgs, lib, ... }:
+let cfg = config.custom.graphical.i3;
+in {
+
+  options = {
+    custom.graphical.i3.enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = "Enable i3 window manager";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    environment.pathsToLink = [
+      "/libexec"
+    ]; # links /libexec from derivations to /run/current-system/sw
+
+    services.xserver = {
+      enable = true;
+
+      desktopManager = { xterm.enable = false; };
+
+      displayManager = { defaultSession = "none+i3"; };
+
+      windowManager.i3 = {
+        enable = true;
+        extraPackages = with pkgs; [
+          i3status # gives you the default i3 status bar
+          i3lock # default i3 screen locker
+          i3blocks # if you are planning on using i3blocks over i3status
+        ];
+      };
+    };
+
+    environment.systemPackages = with pkgs; [
+      #picom # compositor
+      rofi # application
+      maim # takes screenshots
+      xclip
+      dex # starts applications according to .desktop files
+      xss-lock # locks the screen when the system is idle
+      pavucontrol
+      libsForQt5.dolphin
+      playerctl
+      brightnessctl
+      i3blocks
+      autotiling
+      feh # sets the wallpaper
+      nm-tray # NetworkManager tray icon
+    ];
+  };
+}