create seperate packages.nix module

configuration.nix

@@ -2,7 +2,7 @@
 # your system.  Help is available in the configuration.nix(5) man page
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
-{ config, pkgs, ... }:
+{ config, pkgs, inputs, ... }:
 
 {
   imports =
@@ -26,6 +26,10 @@
 
   nix.settings.experimental-features = [ "nix-command" "flakes" ];
 
+  environment.systemPackages = with pkgs; import ./packages.nix {
+    inherit pkgs inputs;
+  };
+
   # Set your time zone.
   time.timeZone = "Europe/Berlin";
 
@@ -100,21 +104,6 @@
   # Allow unfree packages
   nixpkgs.config.allowUnfree = true;
 
-  # List packages installed in system profile. To search, run:
-  # $ nix search wget
-  environment.systemPackages = with pkgs; [
-fastfetch
-htop
-neovim  
-lazygit
-git
-ghostty
- wget
- stow
- fish
- bat
-  ];
-
   # Some programs need SUID wrappers, can be configured further or are
   # started in user sessions.
   # programs.mtr.enable = true;

flake.nix

@@ -5,8 +5,10 @@
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-26.05";
   };
 
-  outputs = { self, nixpkgs }: {
+  outputs = { self, nixpkgs, ... } @ inputs: {
     nixosConfigurations.nixos = nixpkgs.lib.nixosSystem {
+      specialArgs = { inherit inputs; };
+
       modules = [ ./configuration.nix ];
     };
 

packages.nix

@@ -0,0 +1,17 @@
+{ pkgs, inputs, ... }:
+
+with pkgs; 
+
+[
+  fastfetch
+  htop
+  neovim  
+  lazygit
+  git
+  ghostty
+  wget
+  stow
+  fish
+  bat
+  inputs.zen-browser.packages.${pkgs.stdenv.hostPlatform.system}.default
+]