Leveraging nix, nix-os, nix-darwin, and home-manager to apply machine and home configurations
## Structure
Built on the **dendritic** flake-parts pattern via
[`mightyiam/import-tree`](https://github.com/mightyiam/import-tree):
`flake.nix` is just `mkFlake` + `(import-tree ./modules)`. Every `.nix`
file under `./modules/` is a flake-parts module that contributes to the
flake's outputs by option-merging.
```
.
├── flake.nix # mkFlake + (import-tree ./modules)
├── flake.lock # Lockfile (updated daily via GitHub Actions)
├── modules/ # Everything here is a flake-parts module
│ ├── wiring/
│ │ ├── hosts.nix # Central host registry (mkNixos / mkDarwin / mkHome)
│ │ ├── options.nix # Option declarations for non-standard flake outputs
│ │ └── formatter.nix # perSystem.formatter = nixfmt-rfc-style
│ ├── nixos-modules/ # NixOS feature modules (base, zfs, docker, ...)
│ ├── darwin-modules/ # Darwin feature modules (base, homebrew, determinate)
│ ├── home-modules/ # Home Manager feature modules (cli, fish, dev, ...)
│ ├── overlays/ # One flake-parts module per overlay
│ └── packages/ # perSystem.packages registrations
├── hosts/ # NOT loaded by import-tree; referenced from modules/wiring/hosts.nix
│ ├── nixos/
│ │ ├── nas/ # NixOS NAS server (Proxmox, ZFS, Samba, etc.)
│ │ ├── home/ # NixOS VM running in NAS
│ │ └── cloud/ # NixOS VM running in Oracle Cloud
│ ├── darwin/
│ │ ├── Jeffs-M3Pro.nix # Personal MacBook Pro
│ │ └── work-laptop.nix # Work MacBook Pro
│ └── home/
│ ├── jeff/{default,Jeffs-M3Pro,work-laptop,home,cloud}.nix
│ └── nix/{default,nas}.nix
├── packages/ # Custom callPackage-style derivations
└── secrets.nix # Encrypted secrets file (git-crypt)
```
### Key Concepts
- **Dendritic pattern**: every `.nix` under `modules/` is a flake-parts module loaded recursively by `import-tree`
- **Modular architecture**: all features are opt-in modules with `enable` options
- **Explicit host registry**: `modules/wiring/hosts.nix` lists every nixos / darwin / home configuration (adding a host = one line)
## Background
Everyone keeps gushing about how amazing Nix is and I want to get in on the hype cycle
## Goals
- [x] Learn nix
- [x] Mostly reproduce features from my existing [dotfiles](https://github.com/billimek/dotfiles)
- [x] Replace existing ubunut-based 'home VM'
- [x] Expand usage to other shell environments such as WSL, Macbook, etc
- [x] handle secrets - ideally using 1Password and not SOPS - using git-crypt for now
- [x] try agenix for secrets handling
- [ ] introduce the concept of [impermanence](https://github.com/nix-community/impermanence) where appropriate
## References
- [Misterio77/nix-starter-config](https://github.com/Misterio77/nix-starter-configs)
- [How to learn Nix](https://ianthehenry.com/posts/how-to-learn-nix/)
- [home-manager](https://github.com/nix-community/home-manager)
- [Zero to Nix: Everything I Know About Nix & NixOS](https://chetanbhasin.com/articles/zero-to-nix-everything-i-know-about-nix-nixos)
- [Walkthrough of Nix Install and Setup on MacOS (YouTube)](https://www.youtube.com/watch?v=LE5JR4JcvMg)
- [NixOS as a server, part 1: Impermanence](https://guekka.github.io/nixos-server-1/)
- [budimanjojo/dotfiles](https://github.com/budimanjojo/dotfiles/tree/master/nixos)
- [wrmilling/nixos-configuration](https://github.com/wrmilling/nixos-configuration)
- [gshpychka/dotfiles-nix](https://github.com/gshpychka/dotfiles-nix)
- [wimpysworld/nix-config](https://github.com/wimpysworld/nix-config)
## Old Dotfiles
Old dotfiles are still accessible in [archive branch](https://github.com/billimek/dotfiles/tree/archive)