Nix flake for macOS (nix-darwin) and NixOS

Cross-platform flake with Home Manager profiles, shared modules, and per-host overrides.

Quick start

• Prereqs: Nix with flakes enabled (export NIX_CONFIG="experimental-features = nix-command flakes").
• Clone: git clone https://github.com/sm17p/dotfiles.
• macOS apply: darwin-rebuild switch --flake .#sakatagintoki (or .#hijikatatoshiro).
• NixOS apply: sudo nixos-rebuild switch --flake .#<nixos-host>.

Bootstrap with make

• make bootstrap-mac — installs Nix, then nix-darwin using FLAKE (defaults to .#$(hostname)).
• make darwin-rebuild — rebuilds nix-darwin with the current FLAKE.
• Override host: make darwin-rebuild FLAKE=.#sakatagintoki.
• Other helpers: make flake-update, make flake-update-homebrew, make flake-check, make nix-gc, make home-manager-switch.

Layout

• flake.nix: inputs, hosts map, mkHost dispatcher.
• hosts/: per-host settings
  • darwin/<host>/default.nix
  • nixos/<host>/{hardware-configuration.nix,default.nix}
• modules/shared: cross-platform settings (nix config, shells, common pkgs).
• modules/darwin: macOS-specific (fonts, homebrew, touch ID).
• modules/nixos: Linux-specific (placeholder; add boot/fs/impermanence here).
• home-manager/profiles: reusable stacks (common, workstation, server).
• home-manager/programs: HM modules (aliases, fish, firefox, git, tealdeer).
• pkgs/, overlays/: custom packages and overlays.
• .agents/skills/: canonical repo-tracked Agent Skills for cross-tool reuse.

Agent skills

This repo keeps portable Agent Skills in .agents/skills/. That directory is the source of truth for the skill content, but it is not itself a discovery path for every client. Each tool still needs the skills linked or installed into its own native location.

Current skills:

• jj-commit: writes a multi-line jj describe message for an explicit revset.
• jj-push: creates or moves a bookmark and pushes it to origin.

Manual hookup examples:

• Codex: ln -s "$PWD/.agents/skills/jj-commit" ~/.codex/skills/jj-commit and ln -s "$PWD/.agents/skills/jj-push" ~/.codex/skills/jj-push
• Claude Code: ln -s "$PWD/.agents/skills/jj-commit" ~/.claude/skills/jj-commit and ln -s "$PWD/.agents/skills/jj-push" ~/.claude/skills/jj-push
• Gemini CLI: gemini skills link "$PWD/.agents/skills/jj-commit" and gemini skills link "$PWD/.agents/skills/jj-push"

Gemini also supports installing or linking skills through its native skills commands. Codex and Claude pick them up from their own skill directories after the link or copy is in place.

Adding a host

1. Add host metadata in flake.nix under hosts with type (darwin/nixos), system, user, modulesPath, and profiles.
2. Create hosts/<platform>/<host>/default.nix (and hardware-configuration.nix for NixOS).
3. Rebuild with darwin-rebuild switch --flake .#<host> or nixos-rebuild switch --flake .#<host>.

Home Manager profiles

• Profiles live in home-manager/profiles. Each host lists profiles in flake.nix, e.g. ["common" "workstation"].
• common includes shell/tooling (fish, starship, zoxide, atuin, carapace), aliases, catppuccin theme, and defaults.
• workstation and server are stubs to extend for GUI/headless needs.

Common tasks

• Rebuild macOS: darwin-rebuild switch --flake .#<host>.
• Rebuild NixOS: sudo nixos-rebuild switch --flake .#<host>.
• Update inputs: nix flake update.
• Update Homebrew safely: make flake-update-homebrew.

Troubleshooting

• Attribute renames: if pkgs.system warnings appear, use pkgs.stdenv.hostPlatform.system.
• Package renames: on macOS use docker-desktop instead of docker.
• If a profile change doesn’t load, ensure the host’s profiles list in flake.nix includes it.
• If darwin-rebuild fails during brew bundle with unreadable cask or DSL/arity errors, refresh brew-src, nix-homebrew, homebrew-bundle, homebrew-core, and homebrew-cask together instead of editing individual casks.