machine_setup/nix/configuration/flake.nix

# Get a repl for this flake
#   nix repl --expr "builtins.getFlake \"$PWD\""

# TODO maybe use `nix eval --raw .#odo.iso.outPath`

#
# Install on a new machine:
#
# Set
#   me.disko.enable = true;
#   me.disko.offline.enable = true;
#
# Run
#   doas disko --mode destroy,format,mount hosts/recovery/disk-config.nix
#   doas nixos-install --substituters "http://10.0.2.2:8080?trusted=1 https://cache.nixos.org/" --flake ".#recovery"

{
  description = "My system configuration";

  inputs = {
    impermanence.url = "github:nix-community/impermanence";
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    nixpkgs-unoptimized.url = "github:NixOS/nixpkgs/nixos-unstable";
    lanzaboote = {
      url = "github:nix-community/lanzaboote/v0.4.2";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    disko = {
      url = "github:nix-community/disko";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs =
    {
      self,
      nixpkgs,
      nixpkgs-unoptimized,
      disko,
      impermanence,
      lanzaboote,
      ...
    }:
    let
      forAllSystems = nixpkgs.lib.genAttrs nixpkgs.lib.systems.flakeExposed;
      nodes = {
        odo = {
          system = "x86_64-linux";
        };
        quark = {
          system = "x86_64-linux";
        };
        recovery = {
          system = "x86_64-linux";
        };
        i_only_boot_zfs = {
          system = "x86_64-linux";
        };
      };
      nixosConfigs = builtins.mapAttrs (
        hostname: nodeConfig: format:
        nixpkgs.lib.nixosSystem {
          inherit (nodeConfig) system;
          specialArgs = {
            inherit self;

            this_nixos_config = self.nixosConfigurations."${hostname}";

            pkgs-unoptimized = import nixpkgs-unoptimized {
              inherit (nodeConfig) system;
              hostPlatform.gcc.arch = "default";
              hostPlatform.gcc.tune = "default";
            };
          };
          modules = [
            impermanence.nixosModules.impermanence
            lanzaboote.nixosModules.lanzaboote
            disko.nixosModules.disko
            ./configuration.nix
            (./. + "/hosts/${hostname}")
            (./. + "/formats/${format}.nix")
          ];
        }
      ) nodes;
    in
    {
      nixosConfigurations = (builtins.mapAttrs (name: value: value "toplevel") nixosConfigs);
    }
    // {
      packages = (
        forAllSystems (
          system:
          (builtins.mapAttrs (hostname: nodeConfig: {
            iso = (nixosConfigs."${hostname}" "iso").config.system.build.isoImage;
            vm_iso = (nixosConfigs."${hostname}" "vm_iso").config.system.build.isoImage;
            sd = (nixosConfigs."${hostname}" "sd").config.system.build.sdImage;
          }) (nixpkgs.lib.attrsets.filterAttrs (hostname: nodeConfig: nodeConfig.system == system) nodes))
        )
      );
    };
}