Alyssa's dotfiles

These are my dotfiles, managed by Nix, Nix-Darwin and Home Manager (via flakes).

dotfiles/
├── darwin/
|   ├── profiles/
|   |   ├── alyssa.nix
|   |   └── ditto.nix
|   └── configuration.nix
├── home-manager/
|   ├── modules/
|   |   ├── ide/vscode  # extensions & settings
|   |   └── common.nix
|   └── profiles/
|       ├── dev.nix     # for devcontainers
|       ├── home.nix
|       └── work.nix
├── .devcontainer.json  # Nix Package Manager
├── .gitignore          # Nix artifacts
├── flake.lock
├── flake.nix           # Home Manager config
├── justfile            # Task Runner recipes
└── README.md           

Quickstart

What is Nix?

Nix is three things:

Thing	What it is	You might use it to...
Nix (language)	A purely functional language for defining packages and configurations	Write .nix files
Nix (package manager)	A package manager that installs packages in isolation. Like homebrew.	nix profile install nixpkgs#ripgrep
NixOS (os)	A Linux distro configured entirely by Nix files	Run a fully reproducible system

You don't need all three. This repo leverages Home Manager with flakes in a devcontainer (lightweight Debian with Nix Package Manager).

Getting started

You need ONE of these:

Option	What you need	Good for
Devcontainer	Docker + VSCode with Remote Containers	Exploring without installing Nix locally
GitHub Codespaces	A GitHub account	Exploring in the cloud
Local Nix	Nix installed	Already have Nix or want to install it

macOS setup (Darwin)

nix-darwin manages macOS system configuration declaratively, including dock apps, system defaults (defaults write) and Homebrew packages.

Verified end-to-end on a clean tart VM (macOS Tahoe base image), 2026-07-01.

1. Install Nix (official multi-user installer)
2. Enable flakes — the official installer doesn't:
   • echo "experimental-features = nix-command flakes" | sudo tee -a /etc/nix/nix.conf
   • sudo launchctl kickstart -k system/org.nixos.nix-daemon
3. Trust the third-party Homebrew taps (new brew requires this; also needed once on existing machines after a brew update):
   • brew trust cirruslabs/cli getditto/build-infra
   • getditto/build-infra is private — brew bundle clones it over https, so authenticate GitHub first (gh auth login + credential helper) or pre-tap it from an SSH clone.
4. Move aside the /etc files nix-darwin wants to own (first activation only):
   • for f in /etc/nix/nix.conf /etc/bashrc /etc/zshrc; do sudo mv "$f" "$f.before-nix-darwin"; done
5. Bootstrap nix-darwin (once) — build from this repo's pinned input rather than nix run nix-darwin (which resolves upstream HEAD via the GitHub API: version skew + rate-limited on shared IPs):
   • nix build .#darwinConfigurations.ditto.system
   • sudo ./result/sw/bin/darwin-rebuild switch --flake .#ditto
6. Rebuild after changes
   • just _rebuild ditto (the only darwinConfiguration is ditto; alyssa@* names are Linux/devcontainer homeConfigurations)

Gotchas seen on a fresh machine: the user the flake hardcodes (alyssaevans) must exist before switching; the Homebrew prefix must be owned by that user (sudo chown -R alyssaevans /opt/homebrew) because nix-darwin now runs brew as that user; tailscale-app's pkg installer fails inside VMs (system-extension approval) — expected in CI, fine on hardware.

Devcontainer (Linux sandboxed environment)

! does not support nix-darwin

1. Clone this repo
   • gh repo clone alycda/dotfiles
2. Open in VSCode
   • ms-vscode-remote.remote-containers
3. Click "Reopen in Container" when prompted
   • or CMD+SHIFT+P > Dev Containers
4. You now have nix available:
   • nix-env
   • nix profile
   • nix-shell
5. Bootstrap Home Manager (once)
   • nix run home-manager/master -- switch --flake .#alyssa@dev
6. You now have gh, hx, jj and just available:
   • github cli
   • What is jujutsu?
   • rebuild with just or just _rebuild

Other (Flake) devShell (without Home Manager)

• nix develop github:alycda/dotfiles or
• nix develop github:alycda/dotfiles#tools
  • -c cheat -l immediately run a command AND EXIT

Why a devcontainer?

As long as you have docker or an ephemeral environment in the cloud, you can explore my setup without polluting your system.

How it works

Structure

Directory	Tool	Purpose
darwin/	nix-darwin	macOS system config (dock, defaults, homebrew)
home-manager/	Home Manager	User packages and dotfiles (cross-platform)

This keeps package management declarative and reproducible across environments.

---

/etc/nix/nix.conf (without nix-darwin)

allowed-users = @nix-users
build-users-group = nixbld

extra-experimental-features = nix-command flakes

Resources

• Zero to Nix
• Nix Pills — Deep dive (dense but thorough)
• home-manager — Manage dotfiles with Nix
• hame-manager Option Search
• nix-darwin
• devcontainers — Container-based dev environments
• Orbstack — Fast Docker alternative for macOS
• gh repo clone