Use fish shell

modules/home-manager/default.nix

@@ -1,5 +1,6 @@
-{ ... }: {
+{
   imports = [
     ./git.nix
+    ./fish.nix
   ];
 }

modules/home-manager/fish.nix

@@ -0,0 +1,22 @@
+{ pkgs, ... }: {
+  home.packages = with pkgs; [
+    fishPlugins.tide
+  ];
+  
+  programs.fish = {
+    enable = true;
+    interactiveShellInit = ''
+      # no greeting
+      set fish_greeting
+      # vi key binds
+      set -g fish_key_bindings fish_vi_key_bindings
+      # accept completion with ctrl-y
+      bind --mode insert \cy forward-char
+      # initialize prompt
+      tide configure --auto --style=Lean --prompt_colors='16 colors' --show_time=No --lean_prompt_height='Two lines' --prompt_connection=Disconnected --prompt_spacing=Compact --icons='Few icons' --transient=Yes
+    '';
+    shellAbbrs = {
+      la = "ls -lahH";
+    };
+  };
+}

modules/nixos/default.nix

@@ -1,6 +1,5 @@
-# Add your reusable NixOS modules to this directory, on their own file (https://nixos.wiki/wiki/Module).
-# These should be stuff you would like to share with others, not your personal configurations.
 {
-  # List your module files here
-  # my-module = import ./my-module.nix;
+  imports = [
+    ./fish.nix
+  ];
 }

modules/nixos/fish.nix

@@ -0,0 +1,4 @@
+{ pkgs, ... }: {
+  programs.fish.enable = true;
+  users.defaultUserShell = pkgs.fish;
+}