Nix Configuration

This repository holds the Nix configuration for three environments:

• A NixOS desktop
• macOS
• Headless Linux

Why the setup uses Nix

Nix installs packages and applies settings from a declaration. You do not change a machine with a sequence of manual steps. Nix builds the full environment that the declaration specifies. The environment includes each package version and each dependency.

The same declaration always makes the same environment. The previous condition of the machine has no effect on the result.

The declaration is also the documentation of the setup. This repository contains each managed package and each setting. You can do these tasks:

• Find how a component operates
• Change a component
• Remove a component fully

Features

The default shell is Zsh. Zsh starts in mux, a terminal multiplexer. Mux uses Alt + a as the leader key. These two keys follow the leader key:

• Alt + s opens the session tree.
• Alt + w starts the Vim mode.

The mux daemon holds the pseudo-terminals (PTY). The daemon writes pane output and layout changes to a journal. Sessions and scrollback come back after a daemon restart or a machine restart.

The Zsh prompt is minimal. The prompt shows the git state, the jj state, and the direnv state.

A development environment usually uses jj with a colocated git repository. The environment has a .nix directory. This directory holds a flake. The flake declares the development shell for that project. An .envrc file in the root directory starts the flake.

The theme command sets the colors of the command-line interface (CLI). Define a theme in dotfiles/themes/palettes.nix. These programs use the theme:

• eza
• jj
• kitty
• neovim
• opencode

Tools

mux

Mux is a small terminal multiplexer. The mux daemon holds the CLI processes. The terminal emulator does not hold them. The processes continue when the terminal closes. The processes also continue when the SSH connection stops.

Mux supplies these functions:

• Sessions
• Windows
• Panes
• A session tree
• A Vim mode

Use the Vim mode to do these tasks in the scrollback:

• Move the cursor
• Find text
• Copy text

jj in place of git

This setup uses jj in place of git.

jj removes the necessity for HEAD. The working copy is always a commit. Thus you move to a different change with one command: jj edit abc.

jj makes bookmark control easy. The command jj bookmark set master -r abc puts the tip of the master bookmark at commit abc.

The command jj undo reverses each jj command.

jj is compatible with git. jj operates with all git repositories and with all git remotes. Colocation keeps the .git/ directory correct. Each git tool continues to operate correctly.

zoxide in place of cd

An alias makes cd start zoxide. Give a part of a directory name to cd. zoxide then goes to the matching directory that you use most frequently. For example, cd toJPG goes to ~/dev/project123/assets/images/toJPG from any directory.

cd operates as usual when you give a full path.

eza in place of ls

eza is a replacement for ls. eza shows an icon for each file. A Nerd Font is necessary to show the icons correctly.

kitty

The terminal emulator is kitty. The configuration sets a fast smear cursor. The font is IosevkaTermSlab Nerd Font. On macOS, kitty makes the left Option key operate as the Alt key.

Neovim

The Neovim configuration is small. Neovim is the editor for files. The configuration sets up the Language Server Protocol (LSP), treesitter, and nvim-cmp for the necessary languages.

The key bindings stay near the Neovim defaults. Some small changes adapt the default layout from QWERTY to QWERTZ. The vim-easymotion plugin moves the cursor quickly.

First installation

You can apply the Home Manager setup for the CLI on these systems:

• An x86_64 Linux system, which includes the Windows Subsystem for Linux (WSL)
• An AArch64 macOS system

To install the setup, do these steps:

1. Clone the repository into ~/nix:

   git clone https://g.any-0.com/nix.git ~/nix
   

2. Go into the repository:

   cd ~/nix
   

3. Start the bootstrap script:

   ./scripts/cli/cli-bootstrap
   

The script installs Nix if Nix is not on the machine. The script then applies a profile. The script applies the cli profile on x86_64 Linux. The script applies the mac profile on AArch64 macOS.

The scripts expect the repository in ~/nix.

How to apply changes

After the first installation, all scripts in ./scripts/ are on PATH.

To rebuild the configuration, run this command:

switch

The switch script finds the correct target for the platform:

• On macOS, the target is homeConfigurations.mac.
• On NixOS, the target is nixosConfigurations.<hostname>.
• On other Linux systems, the target is homeConfigurations.cli.

Symbolic links connect the files in ./dotfiles/ to the home directory. The links do not go through the Nix store. Thus a change to a dotfile becomes effective immediately. A rebuild is not necessary.

Templates

This repository also contains development templates. templates/README.md gives the documentation for the templates.

To make a new project, run this command:

template python -d my-python-project

The command does these steps:

1. It makes the my-python-project directory.
2. It puts the template in that directory.
3. It writes the source and the date into .nix/README.md.
4. It runs direnv allow.

Do not give the -d <dirname> option if you want to use the current directory.

Technical names and technical verbs

ASD-STE100 permits words that are not in the dictionary when they are technical names (Rule 1.4) or technical verbs (Rule 1.5). This documentation uses these words:

commit, dependency, direnv, dotfile, eza, flake, fzf, git, jj, kitty, macOS, mux, Neovim, Nix, NixOS, pane, profile, repository, scrollback, session, shell, symbolic link, template, zoxide, Zsh