 gram: pool

pool

a Nix package based on microvm.nix

Our machines should be less concerned by the programs they run; so long as each one is in a nice small bounded zone.

Here is phase one.

Philosophy.

You'd like to "drop" your programs onto machines in an ad-hoc manner, using any organizing premise you choose.

When you are simply engaging and disengaging programs, there is no need to keep the program recipe (config) in the same flake as your base machine. This codebase is a collection of those program recipes.

Because your base machine becomes a collection of many "dropped" programs, this operation is called "pooling" programs onto a machine.

microvm.nix helps to reduce resource demand and emphasize caching, using normal Nix approaches.

Dig in.

Using a NixOS machine as your base layer, clone this codebase as /pool.

In your /etc/nixos/flake.nix (you're using flakes, I hope), add:

{ inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.05";
    pool = { url = "/pool"; inputs.nixpkgs.follows = "nixpkgs"; };
  };

  outputs = { microvm, pool, nixpkgs, ... }: let
    lib = nixpkgs.lib; in
  in {
    nixosConfigurations.mach = lib.nixosSystem {
      # ... any nix code you choose.
      modules = [
        sources.microvm.nixosModules.host
        # here, use your machine's primary outbound internet connection.
        (pool.channel.${sources.arch} "eno1")
      ];
    };
  };
}

Make rain.

# `a` is the label of our original machine image.
sudo nix run /pool#a

• You should see a machine spin up;
• the normal login is root, and no passcode required.
• The normal shell is nushell.
• Ensure DHCP assigned an IP addres, using ip a.
• From the base machine, ssh someone@<IP>, passcode abcd1234.
• Sign in easier by filling in roles.<name>.keys = [];, using your SSH key.
• DHCP is used on the 10.0.0.2/24 address space; Nebula is encouraged from there.
• Close the machine, using shutdown now as a superuser.
• /pool is used so images can be recorded in /pool/disc.
• Internet-patching requires super-user permissions, so /pool seems sensible.

Recipes are going to be added as a rapid pace, based on 3 prior years of home-lab nix-code buildup.

Please message code@operand.online and describe any issues you experience.