test: init vm config for mininet

.gitignore

@@ -1,3 +1,4 @@
 /target
 .direnv
 .envrc
+nixos.qcow2

shell.nix

@@ -1,4 +1,11 @@
-{ pkgs ? (import <nixpkgs>) { }, lib ? pkgs.lib }:
+let
+  pkgs = import <nixpkgs> { };
+in
 pkgs.mkShell {
-  buildInputs = with pkgs; [ cargo rustc rustfmt ];
+  buildInputs = with pkgs; [
+    cargo
+    rustc
+    rustfmt
+    nixos-shell
+  ];
 }

vm.nix

@@ -0,0 +1 @@
+vm/vm.nix

vm/vm.nix

@@ -0,0 +1,14 @@
+{ pkgs, ... }:
+{
+  virtualisation = {
+    memorySize = 4 * 1024;
+    cores = 4;
+  };
+
+  programs.mininet.enable = true;
+  users.users.root.packages = [
+    pkgs.python3
+  ];
+
+  system.stateVersion = "25.05";
+}