# NixOS Configuration - Implementation Summary

This document summarizes the NixOS configuration that was created based on the migration plan.

## What Was Created

### Directory Structure

```
nixos/
├── flake.nix                   # NixOS flake (no nix-darwin)
├── flake.lock                  # Flake lockfile (auto-generated)
├── configuration.nix           # System-level configuration
├── hardware-configuration.nix  # Hardware template (MUST be replaced)
├── home.nix                    # Home Manager integration
├── modules/                    # User-level configurations
│   ├── sh.nix                 # Shell (Zsh, Prezto, fzf, zoxide)
│   ├── tmux.nix               # Tmux (WSL paths removed)
│   ├── git.nix                # Git, Lazygit, Jujutsu
│   ├── nvim.nix               # Neovim with 40+ plugins
│   ├── dev.nix                # Dev tools (direnv, visidata)
│   └── task.nix               # Taskwarrior, Timewarrior
├── README.md                   # Installation and usage guide
├── TODO.md                     # Remaining tasks and issues
└── SUMMARY.md                  # This file
```

## Key Changes from Original Configuration

### ✅ Removed
- **nix-darwin** input and outputs
- **macOS/Darwin** conditionals (lines 54-58 in sh.nix)
- **WSL** hard-coded paths (lines 31-32 in tmux.nix)
- **Windows** checks (lines 115-117 in sh.nix)

### ✅ Added
- **System-level configuration** (configuration.nix)
  - Boot loader setup (systemd-boot)
  - Networking with NetworkManager
  - User account definition
  - System timezone and locale
  - Nix flakes enabled

- **Hardware configuration template** (hardware-configuration.nix)
  - Placeholder for NixOS-generated config
  - Must be replaced during installation

### ✅ Modified
- **Home Manager integration**
  - Now runs as NixOS module (not standalone)
  - useGlobalPkgs enabled
  - Removed allowUnfree (handled at system level)

- **Shell configuration** (modules/sh.nix)
  - Removed all platform-specific conditionals
  - Clean Linux-only configuration
  - Added `profileExtra` for .profile sourcing

- **Tmux configuration** (modules/tmux.nix)
  - Commented out note keybindings (C-n, C-p)
  - Paths need to be updated for NixOS environment

- **Development tools** (modules/dev.nix)
  - Custom packages commented out:
    - claude-code
    - opencode
    - gemini-cli
  - TODO notes added for integration

## Validation Status

✅ Flake syntax is valid
✅ Configuration evaluates successfully
✅ All module imports resolve correctly
✅ No blocking errors found

⚠️ Requires `--impure` flag due to NIX_LD settings

## What Needs to Be Done Before Use

### 🔴 Critical (Must Do)
1. **Replace hardware-configuration.nix**
   ```bash
   sudo nixos-generate-config --show-hardware-config > nixos/hardware-configuration.nix
   ```

2. **Update hostname** in configuration.nix
   - Currently set to: "nixos"
   - Change to your actual hostname

3. **Verify boot loader** choice in configuration.nix
   - UEFI: systemd-boot (currently enabled)
   - BIOS: GRUB (commented out)

### 🟡 Important (Should Do)
1. **Verify timezone** in configuration.nix
   - Currently: "Europe/Berlin"

2. **Check locale settings** in configuration.nix
   - Currently: en_US.UTF-8 / de_DE.UTF-8

3. **Verify nvim lua files** exist at:
   - `/home/pan/dev/config/dot/nvim/base.lua`
   - `/home/pan/dev/config/dot/nvim/keymaps.lua`
   - `/home/pan/dev/config/dot/nvim/plugins.lua`
   - `/home/pan/dev/config/dot/nvim/filetype.lua`

### 🟢 Optional (Nice to Have)
1. **Update tmux note paths** in modules/tmux.nix (C-n, C-p keybindings)
2. **Add custom packages** (claude-code, opencode, gemini-cli)
3. **Review and customize** any other settings

## How to Apply

### Test Build (Recommended First)
```bash
cd /home/pan/dev/config/dot/nix/nixos
sudo nixos-rebuild build --flake .#nixos --impure
```

### Apply Configuration
```bash
cd /home/pan/dev/config/dot/nix/nixos
sudo nixos-rebuild switch --flake .#nixos --impure
```

### Update Packages
```bash
nix flake update
sudo nixos-rebuild switch --flake .#nixos --impure
```

## Verification Checklist

After applying the configuration, verify:

- [ ] System boots successfully
- [ ] User 'pan' can login
- [ ] Zsh loads with Prezto theme
- [ ] fzf keybindings work (Ctrl+R)
- [ ] zoxide works (`cd` command)
- [ ] Tmux starts without errors
- [ ] Neovim opens with all plugins
- [ ] Git config shows correct user
- [ ] Lazygit and Jujutsu work
- [ ] Taskwarrior shows version 3.x
- [ ] Direnv loads .envrc files

## Files Preserved

The original Home Manager configuration remains untouched:
- `/home/pan/dev/config/dot/nix/flake.nix`
- `/home/pan/dev/config/dot/nix/common.nix`
- `/home/pan/dev/config/dot/nix/user/*`

You can continue using the Ubuntu setup alongside this NixOS configuration.

## Documentation

- **README.md**: Complete installation and usage guide
- **TODO.md**: Detailed list of remaining tasks and known issues
- **SUMMARY.md**: This file - quick overview and status

## Support

For issues or questions:
1. Check TODO.md for known issues
2. Review README.md for troubleshooting
3. Consult NixOS manual: https://nixos.org/manual/nixos/stable/

## Next Steps

1. ✅ Configuration created successfully
2. ⏳ Replace hardware-configuration.nix
3. ⏳ Update hostname and timezone
4. ⏳ Test build configuration
5. ⏳ Apply configuration
6. ⏳ Verify all components work

Good luck with your NixOS migration! 🚀