Use nix-locate for command-not-found

common/default.nix

@@ -1,6 +1,8 @@
 { config, pkgs, ... }:
 
-{
+let
+  nix-locate = config.inputs.nix-locate.defaultPackage.${config.currentSystem};
+in {
   imports = [
     ./flakes.nix
     ./pia.nix
@@ -43,6 +45,7 @@
     micro
     helix
     lm_sensors
+    nix-locate
   ];
 
   nixpkgs.config.allowUnfree = true;
@@ -63,8 +66,25 @@
 
   nix.gc.automatic = true;
 
-  programs.fish.enable = true;
-  programs.fish.shellInit = ''
-    set fish_greeting
-  '';
+  programs.command-not-found.enable = false;
+
+  programs.fish = {
+    enable = true;
+
+    shellInit = let
+      wrapper = pkgs.writeScript "command-not-found" ''
+        #!${pkgs.bash}/bin/bash
+        source ${nix-locate}/etc/profile.d/command-not-found.sh
+        command_not_found_handle "$@"
+      '';
+    in ''
+      # use nix-locate for command-not-found functionality
+      function __fish_command_not_found_handler --on-event fish_command_not_found
+          ${wrapper} $argv
+      end
+
+      # disable annoying fish shell greeting
+      set fish_greeting
+    '';
+  };
 }

common/flakes.nix

@@ -16,6 +16,9 @@ in {
 
       # pin nixpkgs for system commands such as "nix shell"
       registry.nixpkgs.flake = config.inputs.nixpkgs;
+
+      # pin system nixpkgs to the same version as the flake input
+      nixPath = [ "nixpkgs=${config.inputs.nixpkgs}" ];
     };
   };
 }