nix-operations

name	nix-operations
description	Complete guide for Nix operations including home-manager apply, nix-darwin apply, package installation, rollback procedures, architecture support (Apple Silicon/Intel Mac), and NixOS configuration

Nix operations

Basic operations are performed using make.

• Architecture Support
• Nix
  • Apply home-manager settings
  • Apply all nix-darwin settings
  • Apply nix-darwin-homebrew settings
  • Apply all nix settings
  • Install a new package
  • Rollback

Architecture Support

This repository supports Apple Silicon, Intel Mac, and NixOS. The architecture is auto-detected at build time.

Architecture	nixpkgs	nix-darwin	home-manager
Apple Silicon (aarch64-darwin)	unstable	unstable	unstable
Intel Mac (x86_64-darwin)	unstable	unstable	unstable
NixOS (x86_64-linux)	unstable	N/A	unstable

Nix

NixOS: Apply system and home-manager settings

# Apply all NixOS settings (includes home-manager)
sudo nixos-rebuild switch --flake .#desktop

# Build only (no activation)
sudo nixos-rebuild build --flake .#desktop

# Test configuration temporarily
sudo nixos-rebuild test --flake .#desktop

macOS: Apply home-manager settings (standalone)

# Apply home-manager configuration (update flake + switch)
make home-manager-apply

# Apply home-manager configuration (no flake update)
make home-manager-switch

# Build only (no activation)
make home-manager-build

macOS: Apply all nix-darwin settings

make nix-darwin-apply

Apply nix-darwin-homebrew settings

make nix-darwin-homebrew-apply

Apply nix-darwin-system settings

make nix-darwin-system-apply

Apply nix-darwin-service settings

make nix-darwin-service-apply

macOS: Apply all nix settings

# Update flake inputs and apply all darwin settings
make nix-update-all

# CI environment: Test without actual activation (macOS)
make nix-check-all

Update Nix channels

# Update Nix channel to latest unstable
make nix-channel-update

Update flake inputs

# Update all flake.lock files (darwin, nixos, nixvim)
make flake-update-all

# Update darwin/flake.lock only
make flake-update-darwin

# Update nixos/flake.lock only
make flake-update-nixos

# Update nixvim/flake.lock only
make flake-update-nixvim

Maintenance

# Run Nix garbage collection
make nix-gc

# Completely uninstall Nix
make nix-uninstall

Install a new package

# search package: https://search.nixos.org/packages

# install package
nix profile install nixpkgs#hoge

Upgrade a package

nix profile upgrade hoge

Rollback

1. Check generations

nix-env --list-generations

1   2024-10-17 10:19:29
2   2024-10-17 11:55:16
3   2024-10-17 19:19:37
4   2024-11-06 18:37:37
5   2024-11-06 18:52:58   (current)

2. Rollback

nix-env --rollback

# or

nix-env --switch-generation 3

Special Configuration Handling

Claude Configuration

While most dotfiles configurations are managed through the Nix store for reproducibility and immutability, the Claude configuration is handled as an exception using direct symbolic links.

Rationale:

• Claude Desktop application modifies its configuration files directly during runtime
• The Nix store approach would prevent Claude from updating its own settings
• Direct symbolic links allow bidirectional synchronization between the application and dotfiles

Implementation: The Claude configuration files are linked directly from the dotfiles repository:

macOS (darwin):

~/.claude/CLAUDE.md → ~/git_repos/github.com/barleytea/dotfiles/darwin/home-manager/claude/config/CLAUDE.md
~/.claude/settings.json → ~/git_repos/github.com/barleytea/dotfiles/darwin/home-manager/claude/config/settings.json

NixOS:

~/.claude/CLAUDE.md → ~/git_repos/github.com/barleytea/dotfiles/nixos/home-manager/claude/config/CLAUDE.md
~/.claude/settings.json → ~/git_repos/github.com/barleytea/dotfiles/nixos/home-manager/claude/config/settings.json

This approach enables:

• Claude to modify its configuration files as needed
• Changes to persist in the dotfiles repository automatically
• Version control of Claude settings through git

Configuration Location:

• Dotfiles (darwin): darwin/home-manager/claude/default.nix
• Dotfiles (NixOS): nixos/home-manager/claude/default.nix
• Target directory: ~/.claude/

NixOS: Running Generic Linux Binaries

If you install pre-built binaries that target "generic" Linux environments (for example the Claude CLI), NixOS will refuse to start them with an error like:

Could not start dynamically linked executable: claude
NixOS cannot run dynamically linked executables intended for generic linux environments out of the box.

The nixos/system/default.nix module now enables programs.nix-ld with the common runtime libraries (glibc, libstdc++, openssl, zlib, libX11, etc.) so these binaries can locate their dependencies. After updating the flake, rebuild the machine to pick up the loader:

sudo nixos-rebuild switch --flake .#desktop

If a third-party binary still complains about missing libraries, extend the programs.nix-ld.libraries list in nixos/system/default.nix with the required packages and rebuild again.