Show HN: machine0 – Persistent NixOS VMs You Control from the CLI
43 points - today at 4:01 PM
Hi HN! Excited to launch machine0, a CLI that makes it easy to create, provision and snapshot persistent NixOS (& Ubuntu) VMs.
You can think of machine0 as a modern VPS provider. VMs stay on unless switched-off (with 99.99% uptime), they have static IPs and HTTPS endpoints, 1-60 vCPU, up to 240GB RAM and optionally GPUs. The CLI provides commands to manage lifecycle, snapshots and also provision the VMs using Nix flakes or Ansible playbooks. VMs are priced by the minute of usage.
What makes machine0 unique is that it has first class support for NixOS! In a nutshell, NixOS lets you define your entire OS as code (think Terraform but for your Linux). A flake declares your system state (packages, services, firewall rules, users...) and pins all dependencies via a lockfile. Given the same flake.nix and flake.lock, `nixos-rebuild switch` always produces the exact same system.
The NixOS ecosystem is mature, and flakes are expressive: at the system level you can define packages, what's in /etc, firewall rules, users & groups etc. At the user level, you can define your shell, aliases, tmux and vim config. Having your entire environment defined as code makes it easy to audit what's installed and how things are set up. You can rollback by reverting the last commit. And agents can write the code for you and test it against disposable machine0 VMs.
If you'd like to dive right in, these commands will get you started:
npm install -g @machine0/cli
machine0 new my-vm --image nixos-25-11 # create a new nixos VM
machine0 provision my-vm ./flake#my-profile # provision it using a nix flake
machine0 ssh my-vm # ssh in
machine0 stop my-vm # stop the VM
machine0 images new my-vm my-snapshot # create a snapshot
machine0 new my-clone --image my-snapshot # create a new VM from the snapshot
- Documentation: https://docs.machine0.io/introduction/overview
- machine0 NixOS flakes: https://github.com/fdmtl/machine0-nixos
If you're in the habit of using VMs, or want to know what the NixOS fuss is about, would love for you to give machine0 a try!
Comments
So in my template, I have created the VMs with two disks: first one is for NixOS and is built from an image, and it is read-only. The second is mounted to /var and is used for all system configuration as well as application state. If I have multiple VMs, they can all share the same base image (thin provisioned). That's the mode that I want for my deployments of services, immutable and as stateless as possible. For agent use, its different, you actually want a mutable NixOS root so that the agent can do what it wants.
I built three modes: immutable, semi-mutable, and mutable. mutable removes the read-only lock on the root, and just lets you manage the VM as a pet. semi-mutable adds an ephemeral overlayfs that gets wiped the next time you upgrade the base image. So that gives you kind of the best of both worlds: an immutable read-only base image and the ability to "nix profile add" whatever you (or your agent) wants, but with the contract that these imperatively installed things will disappear the next time you upgrade. Are you planning on adding a LICENSE to your machine0-nixos repo?
exe.dev is great but lurking in my mind is: "how will I replicate this if I ever need to move to AWS etc.." for all the service composition.
Site looks great too