I think this fixes the server

hosts/chmura/configuration.nix

@@ -24,16 +24,24 @@
 
   programs.zsh.enable = true;
 
-  users.users.jacek = {
+  users.users.chmura = {
     isNormalUser = true;
-    extraGroups = ["wheel" "networkmanager"];
+    extraGroups = ["wheel"];
     shell = pkgs.zsh;
+    packages = with pkgs; [
+        curl
+        wget
+        neovim
+        neofetch
+        git
+        wireguard-tools
+    ];
   };
 
   environment = {
     shells = with pkgs; [zsh];
     pathsToLink = [ "/share/zsh" ];
-    sessionVariables = rec {
+    sessionVariables = {
       EDITOR = "nvim";
     };
   };

hosts/niksos/configuration.nix

@@ -17,7 +17,6 @@ in
 {
     nixpkgs.config.allowUnfree = true;
 
-    # Use the GRUB 2 boot loader.
     boot.loader.grub.enable = true;
     boot.loader.grub.device = "/dev/sda";
 
@@ -26,9 +25,6 @@ in
 
     time.timeZone = "Europe/Warsaw";
 
-    # Enable the X11 windowing system.
-    # services.xserver.enable = true;
-
     nix.settings = {
         experimental-features = [
             "flakes"