Add Vagrantfile example.

Vagrantfile

@@ -0,0 +1,38 @@
+Vagrant.configure("2") do |config|
+  config.vm.box = "ubuntu/jammy64"
+  config.vm.network "forwarded_port", guest: 8080, host: 8080
+
+  # Modify this to your needs
+  v.memory = 8192
+  v.cpus = 4
+
+  config.vm.provision "shell", inline: <<-SHELL
+    apt-get update
+    apt-get install -y \
+      ca-certificates \
+      curl \
+      gnupg
+    
+    install -m 0755 -d /etc/apt/keyrings
+    curl -fsSL https://download.docker.com/linux/ubuntu/gpg | gpg --dearmor -o /etc/apt/keyrings/docker.gpg
+    chmod a+r /etc/apt/keyrings/docker.gpg
+
+    echo \
+      "deb [arch="$(dpkg --print-architecture)" signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
+      "$(. /etc/os-release && echo "$VERSION_CODENAME")" stable" | \
+      tee /etc/apt/sources.list.d/docker.list > /dev/null
+
+
+    apt-get update
+    apt-get install -y \
+      docker-ce \
+      docker-ce-cli \
+      containerd.io \
+      docker-buildx-plugin \
+      docker-compose-plugin
+    
+    usermod -aG docker vagrant
+
+    sh <(curl -L https://nixos.org/nix/install) --daemon
+  SHELL
+end