# A Dendritic Nix Flake

Regenerate flake and switch to it.

```shell
nix run .#write-flake
nix flake check
home-manager switch --flake .#desktop
```

```shell
nix flake show --all-systems
```

```shell
nix run nixpkgs#nh home switch -- --configuration john@john-pc-ubuntu .
```

## Host Intent

| Host key | Type | Intent | Entrypoint |
| -------- | ---- | ------ | ---------- |
| `janus` | NixOS (LXC) | Base homelab/service host with local step-ca trust bootstrap (`janus-ca`) and mTLS support. | `modules/hosts/janus/default.nix` |
| `john-kde` | Home Manager (generic Linux) | KDE-focused user environment profile for `john` with desktop + docker + step client tooling. | `modules/hosts/john-kde/default.nix` |
| `john-p14s` | NixOS (laptop) | Main ThinkPad P14s NixOS workstation using hardware presets and desktop/dev modules. | `modules/hosts/john-p14s/default.nix` |
| `john-pc-ubuntu` | Home Manager (generic Linux) | Ubuntu-hosted home profile for `john`, includes desktop/dev tooling and restic backup client settings. | `modules/hosts/john-pc/default.nix` |
| `omen-nixos` | NixOS | Omen machine wired through shared `omen-nixos` + `john` modules. | `modules/hosts/omen-nixos/default.nix` |
| `soteria` | NixOS + Home Manager | Service node running Forgejo + restic server with mTLS and host-local secrets. | `modules/hosts/soteria/soteria.nix` |
| `test-nix` | NixOS (LXC) | Minimal sandbox/test target for validating module composition and remote push/switch flows. | `modules/hosts/test-nix.nix` |

## Layout

- Everything under `./modules` gets auto-imported by `import-tree`

| Directory     | Description |
| ------------- | ----------- |
| `hosts`       | Provides either `homeConfigurations` or `nixosConfigurations` |
| `nix-tools`   | Nix-specific tools, like factory functions for use in the flakes |
| `nixos`       | `flake.modules.nixos` |
| `programs`    | flakes that provide `flake.modules` attributes for specific programs |
| `services`    | flakes that provide configuration for running services |
| `users`       | flakes that provide configuration for individual users with the `flake.factory.user` factory |

## Mechanics

### Flake

The top-level flake is created using [flake-file](https://flake-file.oeiuwq.com/)

```shell
nix flake init -t github:vic/flake-file#default
...
nix run ".#write-flake"
```

This uses `inputs.flake-parts.lib.mkFlake` to create the flake.

The modules are automatically imported from the `./modules` using [import-tree](https://import-tree.oeiuwq.com/).

### [Home Manager](https://flake.parts/options/home-manager.html)

Uses the home-manager module of flake-parts, which is imported in `modules/home-manager/flake-parts.nix`

Looks for options:

- `flake.homeConfigurations`
- `flake.homeModules`

Show exported home configurations:

```shell
nix eval --apply builtins.attrNames .#homeConfigurations
```

### Testing

These commands would are useful for debugging

```shell
SYSTEM=lxc

# Just evaluate (fast, catches config errors)
nix eval .#nixosConfigurations.${SYSTEM}.config.system.build.toplevel

# Full build (slower, produces a bootable system)
nix build .#nixosConfigurations.${SYSTEM}.config.system.build.toplevel
```

### Remote Deploy

```shell
nixos-rebuild switch --flake .#lxc --target-host root@fded:fb16:653e:25da:be24:11ff:fea0:753f
```