Zsh & Oh My Zsh — Complete Shell Enhancement Guide

# Check if Zsh is installed
zsh --version

# macOS (pre-installed)
# Ubuntu/Debian
sudo apt install zsh

# Fedora
sudo dnf install zsh

# Arch
sudo pacman -S zsh

# Make Zsh the default shell
chsh -s $(which zsh)
# Log out and back in, or:
exec zsh

# Via curl
sh -c "$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"

# Via wget
sh -c "$(wget -O- https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"

# The installer:
# 1. Backs up existing ~/.zshrc to ~/.zshrc.pre-oh-my-zsh
# 2. Creates a new ~/.zshrc with default config
# 3. Sets the theme to robbyrussell

# ~/.zshrc — Path to Oh My Zsh installation
export ZSH="$HOME/.oh-my-zsh"

# Theme
ZSH_THEME="robbyrussell"
# List themes: https://github.com/ohmyzsh/ohmyzsh/wiki/Themes

# Plugins
plugins=(
    git
    docker
    docker-compose
    node
    npm
    python
    pip
    kubectl
    helm
    terraform
    aws
    history
    common-aliases
    colored-man-pages
    sudo       # Press Esc twice to add sudo
    extract    # Extract any archive with 'x'
    z          # Directory jumping (similar to zoxide)
    web-search # Search from terminal
)

source $ZSH/oh-my-zsh.sh

# Add to ~/.zshrc after the Oh My Zsh source line

# Navigation
alias ..='cd ..'
alias ...='cd ../..'
alias ....='cd ../../..'

# Listing
alias l='ls -lah'
alias ll='ls -lh'
alias la='ls -lAh'

# Git
alias gst='git status'
alias gco='git checkout'
alias gcb='git checkout -b'
alias gaa='git add --all'
alias gcmsg='git commit -m'
alias gp='git push'
alias gl='git log --oneline --graph --all'

# Docker
alias dps='docker ps'
alias dcu='docker compose up -d'
alias dcd='docker compose down'

# Safety
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Most-used git aliases
gst      # git status
gaa      # git add --all
gcmsg    # git commit -m
gp       # git push
gl       # git log --oneline --graph --all
gcb      # git checkout -b
gco      # git checkout
gd       # git diff
gpl      # git pull
gsta     # git stash
gstp     # git stash pop
grhh     # git reset HEAD --hard

# Type a command, then press Esc twice:
apt update
# Becomes:
sudo apt update

x file.tar.gz
x file.zip
x file.rar
x file.tar.bz2
# No need to remember tar flags

google "how to use zsh"
stackoverflow "python error"
github "oh-my-zsh"
wiki "z shell"

z projects    # Jump to most-used "projects" dir
z src         # Jump to src directory matching pattern
z proj<TAB>   # Tab completion shows matches

# Measure Zsh startup time
time zsh -i -c exit

# Profile Oh My Zsh startup
zmodload zsh/zprof
# Add at the top of ~/.zshrc:
zmodload zsh/zprof
# Add at the bottom:
zprof

# 1. Use only the plugins you need
plugins=(git extract sudo)  # Minimal set

# 2. Lazy-load heavy plugins
# Instead of loading kubectl plugin, load completion manually
source <(kubectl completion zsh)

# 3. Use shorter theme
ZSH_THEME="minimal"

# 4. Disable auto-update
DISABLE_UPDATE_PROMPT=true
DISABLE_AUTO_UPDATE=true

# 5. Speed up git plugin (disable check-for-changes)
DISABLE_UNTRACKED_FILES_DIRTY="true"

# agnoster — Powerline-style, shows git info
ZSH_THEME="agnoster"

# powerlevel10k — Fast, customizable, many features
# Install separately:
git clone --depth=1 https://github.com/romkatv/powerlevel10k.git \
    ${ZSH_CUSTOM:-$HOME/.oh-my-zsh/custom}/themes/powerlevel10k
ZSH_THEME="powerlevel10k/powerlevel10k"

# Spaceship — Minimal, shows runtime info
ZSH_THEME="spaceship"

# bira — Clean, shows git and venv
ZSH_THEME="bira"

# Minimal — Fast, simple
ZSH_THEME="minimal"

# For powerlevel10k, run the configuration wizard
p10k configure

# Powerlevel10k config file: ~/.p10k.zsh
# Edit to customize prompt elements

# Recursive globbing (** matches any depth)
ls **/*.py          # All Python files recursively
ls src/**/*.test.*  # All test files in src/

# Glob qualifiers
ls *(.)             # Files only
ls *(/)             # Directories only
ls *(Lk+100)        # Files larger than 100KB
ls *(Lm-1)          # Files smaller than 1MB
ls *(om[1,5])       # 5 most recently modified files

# Case-insensitive completion
zstyle ':completion:*' matcher-list 'm:{a-z}={A-Z}'

# Menu selection
zstyle ':completion:*' menu select

# Verbose completion
zstyle ':completion:*' verbose true

# Group matches
zstyle ':completion:*' format '%B%d%b'
zstyle ':completion:*' group-name ''

# ~/.zshrc
HISTFILE="$HOME/.zsh_history"
HISTSIZE=100000
SAVEHIST=100000

setopt SHARE_HISTORY           # Share history across sessions
setopt HIST_EXPIRE_DUPS_FIRST  # Remove duplicates first
setopt HIST_IGNORE_DUPS        # Don't record duplicates
setopt HIST_IGNORE_SPACE       # Don't record commands starting with space
setopt HIST_REDUCE_BLANKS      # Remove unnecessary blanks
setopt EXTENDED_HISTORY        # Record timestamps

# Create a custom plugin
mkdir -p $ZSH_CUSTOM/plugins/myplugin

# Create plugin file
cat > $ZSH_CUSTOM/plugins/myplugin/myplugin.plugin.zsh << 'EOF'
# Custom aliases and functions
alias myip='curl -s https://api.ipify.org'
alias weather='curl -s wttr.in'
alias cheat='curl -s cheat.sh'

# Custom function
extract_urls() {
  grep -oP 'https?://[^ ]+' "$1" | sort -u
}
EOF

# Add to plugins list in ~/.zshrc
plugins=(... myplugin)

# Update Oh My Zsh
omz update

# Check for broken configuration
zsh -n ~/.zshrc

# Reset Oh My Zsh
# Move old config and reinstall
mv ~/.oh-my-zsh ~/.oh-my-zsh.bak
sh -c "$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)"