feat(nixos): add initial NixOS configuration and hardware setup

nixos/configuration.nix

@@ -0,0 +1,168 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
+
+{
+  imports =
+    [ # Include the results of the hardware scan.
+      ./hardware-configuration.nix
+    ];
+
+  # Bootloader.
+  boot.loader.grub.enable = true;
+  boot.loader.grub.device = "/dev/sda";
+  boot.loader.grub.useOSProber = true;
+
+  boot.kernelParams = [ "quiet" ];
+  boot.extraModulePackages = [ config.boot.kernelPackages.amneziawg ];
+  boot.kernelModules = [ "amneziawg" ];
+
+  programs.nix-ld.enable = true;
+  programs.nix-ld.libraries = with pkgs; [
+    stdenv.cc.cc
+    zlib
+    fuse3
+    icu
+    nss
+    openssl
+    curl
+    expat
+  ];
+
+  networking.hostName = "nixos-vm";
+  networking.networkmanager.enable = true;
+  time.timeZone = "Europe/Moscow";
+
+  i18n.defaultLocale = "en_US.UTF-8";
+
+  i18n.extraLocaleSettings = {
+    LC_ADDRESS = "ru_RU.UTF-8";
+    LC_IDENTIFICATION = "ru_RU.UTF-8";
+    LC_MEASUREMENT = "ru_RU.UTF-8";
+    LC_MONETARY = "ru_RU.UTF-8";
+    LC_NAME = "ru_RU.UTF-8";
+    LC_NUMERIC = "ru_RU.UTF-8";
+    LC_PAPER = "ru_RU.UTF-8";
+    LC_TELEPHONE = "ru_RU.UTF-8";
+    LC_TIME = "ru_RU.UTF-8";
+  };
+
+  services.xserver.enable = true;
+  services.xserver.displayManager.sddm.enable = true;
+  services.xserver.displayManager.sddm.wayland.enable = true;
+  services.xserver.desktopManager.plasma5.enable = true;
+
+  environment.sessionVariables.NIXOS_OZONE_WL = "1";
+
+  # Configure keymap in X11
+  services.xserver.xkb = {
+    layout = "us";
+    variant = "";
+  };
+
+  # Enable CUPS to print documents.
+  services.printing.enable = true;
+
+  services.pulseaudio.enable = false;
+  security.rtkit.enable = true;
+  services.pipewire = {
+    enable = true;
+    alsa.enable = true;
+    alsa.support32Bit = true;
+    pulse.enable = true;
+  };
+
+  # Define a user account. Don't forget to set a password with ‘passwd’.
+  users.users.ada = {
+    isNormalUser = true;
+    description = "ada";
+    extraGroups = [ "networkmanager" "wheel" ];
+    packages = with pkgs; [
+      vim
+      neovim
+      code
+      jetbrains.idea-community
+      tmux
+      zsh
+      oh-my-zsh
+      fzf
+      ripgrep
+      fd
+      bat
+      eza
+      lsd
+      git
+      gh
+      lazygit
+      curl
+      wget
+      jq
+      nix-output-monitor
+      nvd
+      nix-tree
+      comma
+      htop
+      btop
+      tree
+    ];
+  };
+
+
+
+  environment.systemPackages = with pkgs; [
+    vim
+    wget
+    git
+    curl
+    amneziawg-tools
+    nix-output-monitor
+    nvd
+    nix-tree
+    comma
+    htop
+    neofetch
+  ];
+
+  nix = {
+    package = pkgs.nix;
+    settings = {
+      experimental-features = [ "nix-command" "flakes" ];
+      auto-optimise-store = true;
+    };
+    gc = {
+      automatic = true;
+      dates = "weekly";
+      options = "--delete-older-than 7d";
+    };
+  };
+
+  nixpkgs.config.allowUnfree = true;
+
+  programs.firefox.enable = true;
+  programs.amnezia-vpn.enable = true;
+  programs.mtr.enable = true;
+  programs.gnupg.agent = {
+    enable = true;
+    enableSSHSupport = true;
+  };
+
+  services.openssh = {
+    enable = true;
+    settings = {
+      PasswordAuthentication = false;
+      PubkeyAuthentication = true;
+    };
+  };
+
+  # Open ports in the firewall.
+  networking.firewall.allowedTCPPorts = [ 22 ];
+
+  virtualisation.virtualbox.guest.enable = true;
+  virtualisation.virtualbox.guest.dragAndDrop = true;
+  virtualisation.virtualbox.guest.clipboard = true;
+
+  system.stateVersion = "25.05";
+}

nixos/flake.nix

@@ -0,0 +1,23 @@
+{
+  description = "NixOS Configuration Flake";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    nixos-hardware.url = "github:nixos/nixos-hardware";
+  };
+
+  outputs = { self, nixpkgs, nixos-hardware }:
+    let
+      system = "x86_64-linux";
+      pkgs = nixpkgs.legacyPackages.${system};
+    in
+    {
+      nixosConfigurations.nixos-vm = nixpkgs.lib.nixosSystem {
+        inherit system;
+
+        modules = [
+          ./nixos/configuration.nix
+        ];
+      };
+    };
+}

nixos/hardware-configuration.nix

@@ -0,0 +1,30 @@
+# Do not modify this file!  It was generated by ‘nixos-generate-config’
+# and may be overwritten by future invocations.  Please make changes
+# to /etc/nixos/configuration.nix instead.
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports = [ ];
+
+  boot.initrd.availableKernelModules = [ "ata_piix" "ohci_pci" "ehci_pci" "ahci" "sd_mod" "sr_mod" ];
+  boot.initrd.kernelModules = [ ];
+  boot.kernelModules = [ ];
+  boot.extraModulePackages = [ ];
+
+  fileSystems."/" =
+    { device = "/dev/disk/by-uuid/2bb3bd25-1bc0-408f-945e-9150e4a10255";
+      fsType = "ext4";
+    };
+
+  swapDevices = [ ];
+
+  # Enables DHCP on each ethernet and wireless interface. In case of scripted networking
+  # (the default) this is the recommended approach. When using systemd-networkd it's
+  # still possible to use this option, but it's recommended to use it in conjunction
+  # with explicit per-interface declarations with `networking.interfaces.<interface>.useDHCP`.
+  networking.useDHCP = lib.mkDefault true;
+  # networking.interfaces.enp0s3.useDHCP = lib.mkDefault true;
+
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
+  virtualisation.virtualbox.guest.enable = true;
+}