add-package

name: add-package description: | Add a package to this Home Manager dotfiles repo. Use when the user asks to install, add, or migrate a package — examples "add jq", "ripgrep を入れて", "lazygit 入れたい", "brew install foo を Nix に移したい", "uv を Nix で", "kubectl 追加して". The skill picks the right module under home/, checks nixpkgs and programs.<X> availability, edits the Nix file, validates with home-manager build, applies via home-manager switch, and verifies the binary resolves through Nix.

add-package

Add a package to the Home Manager dotfiles config in the right place.

Repo module layout

• home/default.nix — sessionVariables, programs.nh, ghostty link, base nix settings
• home/fish.nix — fish + atuin/direnv/zoxide/mise/carapace integrations
• home/git.nix — git/delta/gh/lazygit + ghq + power_pull
• home/neovim.nix — programs.neovim + nvim/ symlink
• home/packages.nix — programs.bat + general home.packages

Non-nixpkgs sources (3 fish plugins) live as flake inputs in flake.nix.

Decision flow

1. Identify the package (e.g. "ripgrep" → pkgs.ripgrep).

2. Check availability:

   • nix search nixpkgs <name> (or nix-env -qaP <name>) confirms it exists.
   • GUI app / macOS cask / not in nixpkgs → keep on brew, note why.

3. Pick the HM home:

   • HM has programs.<X> module (e.g. bat, gh, git, delta, atuin, direnv, zoxide, mise, carapace, lazygit, nh, neovim, fish) → enable the module so config is declarative too. If it integrates with fish, set enableFishIntegration = true.
   • Else home.packages.

4. Pick the file:

   • Tool integrates with fish (atuin/direnv/zoxide/mise/carapace/...) → home/fish.nix
   • Git / GitHub ecosystem → home/git.nix
   • Neovim-related → home/neovim.nix
   • General CLI → home/packages.nix
   • Don't spread home.packages across modules; prefer packages.nix unless the tool's programs.<X> block already lives elsewhere (then keep them together).

5. Edit with Edit tool. Keep alphabetical order within each grouped list (matches the existing style; bat eza fd fzf ripgrep etc.).

6. Validate: home-manager build --flake .#nwiizo. On error, inspect and fix; do not switch on a failed build.

7. Apply: home-manager switch --flake .#nwiizo.

8. Verify: type -p <name> resolves to ~/.nix-profile/bin/<name> (or, for programs.<X>, the binary still works and any generated config is in place).

9. If migrating from brew: ask the user before brew uninstall <name>. Some users want the brew copy as a fallback.

Discover migration candidates

When the user asks what to migrate from brew:

comm -13 \
  <(brew list --formula | sort -u) \
  <(ls ~/.nix-profile/bin/ | sort -u)

• Skip brew list --cask (GUI apps stay on brew).
• Prefer tools with a programs.<X> HM module — declarative config wins.
• For tools with non-trivial config, check if the HM module exposes settings so the existing ~/.config/<tool>/... can be translated.

Don't

• Don't add a package twice (e.g. via both home.packages and programs.<X>.enable).
• Don't auto-brew uninstall without explicit confirmation.
• Don't skip home-manager build validation.
• Don't add packages directly to home/default.nix — pick a domain module (packages.nix, git.nix, ...).
• Don't reformat unrelated parts of the file. After editing, run nix fmt -- --check ./home/<file>.nix if a format check is needed.