NixConfig

A cross-machine, cross-OS Nix flake configuration for NixOS and macOS (nix-darwin), managing packages, dotfiles and system settings for a single user across multiple hosts.

Built around the Dendritic Pattern.

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The Dendritic Pattern

This repository follows the Dendritic Pattern: every .nix file (except the entry points flake.nix and host default.nix files) is a flake-parts module. Modules are organised by feature, not by host or configuration class. A single feature file covers NixOS system config, nix-darwin system config and Home Manager config all in one place.

# modules/features/terminal.nix — one file owns everything "terminal" touches
{
  flake.modules.nixos.terminal     = { ... };   # system-level (NixOS)
  flake.modules.darwin.terminal    = { ... };   # system-level (macOS)
  flake.modules.homeManager.terminal = { ... }; # user-level (both platforms)
}

import-tree auto-imports every .nix file under modules/, so dropping a new file in is enough — no manual registration in flake.nix needed.

Why this pattern?

• Locality - all config for a feature lives in one file.
• No specialArgs pass-thru - values are shared through the top-level config attrset instead of being threaded through specialArgs/extraSpecialArgs.
• Free file paths - files can be renamed, moved, or split without breaking anything. The path is just a name.
• Automatic importing - any .nix file added under modules/ is picked up immediately.

Sources & further reading

• mightyiam/dendritic — canonical pattern documentation
• NixOS Discourse - The dendritic pattern — original discussion thread
• YouTube — Elevate Your Nix Config With Dendritic Pattern — video walkthrough

---

Folder Architecture

NixConfig/
├── flake.nix                        # Entry point — delegates to flake-parts via import-tree
├── flake.lock                       # Pinned input revisions
│
├── modules/                         # All Nix configuration logic (auto-imported by import-tree)
│   ├── flake-modules.nix            # Registers flake-parts + home-manager flake modules
│   ├── helpers.nix                  # Global options: username, supported systems, path helpers
│   ├── features/                    # Feature modules — one file per capability
│   ├── hosts/
│   │   ├── nixbook/                 # Primary Linux host (fully configured)
│   │   │   ├── default.nix          # Assembles nixosConfiguration from feature modules
│   │   │   ├── configuration.nix    # Boot, networking, display manager, users, locale
│   │   │   └── hardware-configuration.nix  # LUKS, GPU (AMD+Nvidia PRIME), Bluetooth
│   │   ├── macbook/
│   │   │   ├── default.nix          # Personal macOS host (nix-darwin + Homebrew)
│   │   │   └── configuration.nix    # macOS system settings, apps, Homebrew config
│   │   └── macbook-cookunity/
│   │       ├── default.nix          # Work macOS host (nix-darwin + Homebrew)
│   │       └── configuration.nix    # macOS system settings, apps, Homebrew config
│   └── users/
│       └── christopher.nix          # Minimal Home Manager base: username + stateVersion
└── assets/                          # Static files symlinked into $HOME at activation time

Key design decisions

Decision	Rationale
config.flake.username	Username is declared once in helpers.nix, never hardcoded elsewhere
helpers.mkAssetsPath	Returns a Nix store path to assets/<path> — used at eval time
helpers.mkAssetsStringPath	Returns a string ~/NixConfig/assets/<path> — used for live symlinks that must not enter the store
helpers.mkConfigPath / mkHomePath	All ~/.config/ and ~/ paths go through helpers; no raw string paths scattered around
helpers.mkHybrid	Wraps a Home Manager module to conditionally apply config per platform (Linux vs. macOS)
mkOutOfStoreSymlink for assets/nvim/	Neovim config edits take effect immediately without a rebuild
Proton Pass secret pipeline	env.template + secure-env-refresh.sh + systemd service — secrets never touch the Nix store

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Hosts

Host	Platform	Status	Description
nixbook	x86_64-linux	Active	Main desktop — AMD+Nvidia PRIME, LUKS, Niri, SDDM
macbook	aarch64-darwin	Active	Personal MacBook — nix-darwin + Homebrew
macbook-cookunity	aarch64-darwin	Active	Work MacBook — nix-darwin + Homebrew

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Getting Started

Validate (no build)

nix flake check

Build without applying

nix build .#nixosConfigurations.nixbook.config.system.build.toplevel

Dry-run (build without activating)

sudo nixos-rebuild dry-activate --flake .#nixbook

Apply — Linux

sudo nixos-rebuild switch --flake .#nixbook

Apply — macOS

darwin-rebuild switch --flake .#macbook
# or using the shell alias:
switch

Update all inputs

nix flake update

Update a single input

nix flake update nixpkgs

Format all Nix files

nixfmt **/*.nix