Add fish wrapper and make it my default shell

modules/system/common/default.nix

@@ -3,8 +3,11 @@
   configurationName,
   lib,
   pkgs,
+  inputs',
+  username,
   ...
 }: let
+  inherit (inputs'.settei.packages) fish;
   sharedConfig = {
     settei.user.config = {
       programs.git = {
@@ -22,7 +25,17 @@
           push.followTags = true;
         };
       };
+
+      programs.fish.enable = true;
     };
+
+    programs.fish.enable = true;
+    environment.shells = [fish];
+    users.users.${username}.shell = fish;
+
+    # NixOS' fish module doesn't allow setting what package to use for fish,
+    # so I need to override the fish package.
+    nixpkgs.overlays = [(_: _: {inherit fish;})];
   };
 
   linuxConfig = lib.optionalAttrs isLinux {

wrappers/default.nix

@@ -18,20 +18,30 @@
         ./starship
         ./helix
         ./rash
+        ./fish
       ];
     };
     all-packages = wrapped.config.build.packages;
+
+    fish-base = pkgs.fish;
+    fish-wrapped = all-packages.fish;
+    fish = pkgs.symlinkJoin {
+      inherit (fish-base) name meta passthru;
+      paths = [ fish-wrapped fish-base ];
+    };
+
     base-packages = pkgs.symlinkJoin {
       name = "settei-base";
-      paths = with all-packages; [
-        helix
+      paths = [
+        all-packages.helix
+        fish
       ];
     };
   in {
     packages =
       all-packages
       // {
-        inherit base-packages;
+        inherit base-packages fish;
       };
   };
 }

wrappers/fish/config.fish

@@ -0,0 +1,9 @@
+# Abbreviations
+abbr --add --global -- flake-update 'nix flake lock --update-input'
+abbr --add --global -- ns 'nix shell'
+abbr --add --global -- nss 'nix search'
+abbr --add --global -- vim hx
+
+# Aliases
+alias cat bat
+alias l 'eza -lah --group-directories-first --icons'

wrappers/fish/default.nix

@@ -0,0 +1,15 @@
+{lib, pkgs, ...}: {
+  # TODO: Fix once https://github.com/viperML/wrapper-manager/issues/14 is resolved
+  wrappers.fish = {
+    basePackage = pkgs.runCommandNoCC "fish-binary" {} ''
+      install -D -m555 ${lib.getExe pkgs.fish} "$out/bin/fish"
+    '';
+
+    prependFlags = [
+      "-C"
+      "source ${./config.fish}"
+    ];
+
+    pathAdd = with pkgs; [bat eza];
+  };
+}