A Pro Terminal on macOS

Introduction

If you work as a DevOps or SRE engineer on macOS, the terminal is where you deploy containers, talk to Kubernetes, run Terraform and investigate incidents. A good configuration will not make you a better engineer, but it removes friction and makes the current context visible before you press Enter.

This guide sets up iTerm2, Zsh, Oh My Zsh and Powerlevel10k, then adds the Kubernetes tools kubectx, kubens and k9s. Every command, alias and key binding was checked against the official repositories and documentation listed at the end of the page. Treat the choices as suggestions and adapt them to your team.

Prerequisites: Homebrew and Zsh

Homebrew installs most of the tools in this guide. The commands assume you use Zsh: run echo $SHELL to check.

Install Homebrew

Homebrew is a package manager for macOS. This is the installation command given in the official Homebrew installer repository. Read a script before you pipe it into a shell, and check the official documentation for the current requirements (Homebrew lists the Xcode Command Line Tools as a requirement for building formulae from source).

$ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Install iTerm2 and the font

iTerm2 is a terminal emulator for macOS that offers split panes, profiles and search. Powerlevel10k draws icons that need a font with extra glyphs.

Install iTerm2

$ brew install --cask iterm2

Install the MesloLGS NF font

Powerlevel10k recommends the font MesloLGS NF. Without a suitable font, some icons in the prompt are drawn as broken characters. The Powerlevel10k README describes two ways to install it:

• Automatic, iTerm2 only: when you run p10k configure later in this guide, answer Yes when it asks whether to install Meslo Nerd Font.
• Manual: download the four .ttf files linked in the “Manual font installation” section of the Powerlevel10k README, double-click each one and click Install. Then open iTerm2, press Cmd + , to open the preferences, go to Profiles then Text and set Font to MesloLGS NF.

Oh My Zsh, Powerlevel10k and two Zsh add-ons

Oh My Zsh is a framework that manages Zsh configuration, plugins and themes. Powerlevel10k is a Zsh theme that draws the prompt.

Install Oh My Zsh

This is the command from the Oh My Zsh README. The installer keeps your previous ~/.zshrc as ~/.zshrc.pre-oh-my-zsh and creates a new one.

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

Install Powerlevel10k

Use the Oh My Zsh method from the Powerlevel10k README:

$ git clone --depth=1 https://github.com/romkatv/powerlevel10k.git "${ZSH_CUSTOM:-$HOME/.oh-my-zsh/custom}/themes/powerlevel10k"

Then set ZSH_THEME="powerlevel10k/powerlevel10k" in ~/.zshrc (the full file is shown in the next section). Homebrew also has a powerlevel10k formula, but do not install the theme both ways: pick one.

Install the tools used by the configuration

These two add-ons are installed with Homebrew and sourced from ~/.zshrc. The optional thefuck corrects mistyped commands.

$ brew install zsh-autosuggestions zsh-syntax-highlighting
$ brew install thefuck

A ~/.zshrc for SRE work

Edit your existing file instead of overwriting it. The order of the lines matters.

First make a backup, then open the file in your editor:

$ cp ~/.zshrc ~/.zshrc.bak
$ open -e ~/.zshrc

Make the relevant parts look like this. The instant prompt block must stay at the very top, and zsh-syntax-highlighting must be the last thing sourced, as its documentation requires. If you run p10k configure later, the wizard adds the instant prompt block and the ~/.p10k.zsh line for you.

# Powerlevel10k instant prompt: keep this block at the very top of ~/.zshrc
if [[ -r "${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh" ]]; then
  source "${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh"
fi

# Oh My Zsh location and theme
export ZSH="$HOME/.oh-my-zsh"
ZSH_THEME="powerlevel10k/powerlevel10k"

# Oh My Zsh plugins (explained in the next section)
plugins=(git z sudo docker docker-compose kubectl helm terraform aws brew macos command-not-found history-substring-search colored-man-pages copypath extract safe-paste gitignore)

source $ZSH/oh-my-zsh.sh

# The Fuck (optional): defines the "fuck" alias
command -v thefuck >/dev/null && eval "$(thefuck --alias)"

# Aliases that the plugins above do not provide
alias kctx="kubectx"
alias kns="kubens"
alias lzd="lazydocker"

# Autosuggestions (HOMEBREW_PREFIX is set by the brew plugin)
source "$HOMEBREW_PREFIX/share/zsh-autosuggestions/zsh-autosuggestions.zsh"

# Powerlevel10k configuration, created by "p10k configure"
[[ ! -f ~/.p10k.zsh ]] || source ~/.p10k.zsh

# zsh-syntax-highlighting must be sourced last
source "$HOMEBREW_PREFIX/share/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh"

Restart Zsh to apply the changes. The Powerlevel10k README warns against source ~/.zshrc and recommends restarting Zsh instead:

$ exec zsh

What each Oh My Zsh plugin gives you

Every plugin below has a README in the Oh My Zsh repository under plugins/. Read the README of a plugin before you rely on it, because aliases can be more powerful than they look.

Git, navigation and sudo

$ gst
# git status
$ ga .
# git add .
$ gcmsg "fix: kubectl timeout issue"
# git commit --message "..."
$ gp
# git push

$ z prod-eu1

Prediction and history

$ kubectl logs
# press Up to cycle through matching commands from your history

$ git brnch
git: 'brnch' is not a git command. See 'git --help'.
$ fuck
git branch [enter/↑/↓/ctrl+c]

Docker, Kubernetes and Terraform

$ k get pods
# k is an alias for kubectl
$ kgp
# kubectl get pods
$ kgpa
# kubectl get pods --all-namespaces
$ tfp
# terraform plan
$ dps
# docker ps

Utilities

$ example-command
The program 'example-command' is currently not installed. You can install it by typing:
 brew install example-formula

$ extract backup.tar.gz
$ extract config.zip
$ extract archive.7z

$ copypath
# copies the absolute path of the current directory to the clipboard
$ copypath deploy.yaml
# copies the absolute path of that file

$ gi list
$ gi terraform
$ gi terraform python macos >> .gitignore

Cloud and macOS

$ asp my-profile
# sets AWS_PROFILE for this shell

$ ofd
# open the current directory in Finder
$ quick-look report.pdf
# Quick Look preview of a file
$ rmdsstore
# remove .DS_Store files recursively in a directory

Configure Powerlevel10k and make production visible

Powerlevel10k has a configuration wizard, and it can color the Kubernetes context differently for production.

Run the wizard. It also offers to install the recommended font in iTerm2:

$ p10k configure

Choose the prompt style you find readable. If you show the time in the prompt, a 24-hour format is easier to compare with logs and dashboards, whichever time zone your team uses. The wizard writes ~/.p10k.zsh. You can run it again at any time.

What the Kubernetes segment shows, and when

The configuration files shipped with Powerlevel10k include segments for the Kubernetes context (kubecontext), the Terraform workspace (terraform) and the AWS profile (aws). By default, several of them are shown only while the command you are typing uses a related tool. In the shipped Classic config, the Kubernetes context appears when you type commands such as kubectl, helm, kubens, kubectx or k9s, and the AWS profile appears for commands such as aws and terraform. The config file says you can remove the SHOW_ON_COMMAND line to show a segment all the time.

Color production contexts differently

Red for production is not the default. The default config only has a commented example. To enable it, edit ~/.p10k.zsh, find the POWERLEVEL9K_KUBECONTEXT_CLASSES array and uncomment or add a pattern that matches your production context names. Colors are numbers from the 256-color palette:

typeset -g POWERLEVEL9K_KUBECONTEXT_CLASSES=(
  '*prod*' PROD
  '*' DEFAULT)
typeset -g POWERLEVEL9K_KUBECONTEXT_PROD_FOREGROUND=196

The pattern '*prod*' only works if your contexts have “prod” in their name. Adapt it to your naming convention, then restart Zsh with exec zsh.

A ready-to-copy ~/.p10k.zsh

A compact, hand-maintained alternative to running the wizard: drop this in, adjust the colors to taste, then restart Zsh.

This file only sets what the setup on this page actually uses: the segments tied to the plugins introduced above (Git, Kubernetes, Terraform, AWS). It is not the full file the wizard writes, which documents every available segment with extensive comments; run p10k configure for that, or see the Powerlevel10k README, linked under “Official documentation” below, for the complete option reference.

# ~/.p10k.zsh
# Hand-maintained companion to the ~/.zshrc from "A ~/.zshrc for SRE work" above.
# Sourced automatically by: [[ ! -f ~/.p10k.zsh ]] || source ~/.p10k.zsh
# Only sets what that setup actually uses (git, kubectl, terraform, aws).
# Run "p10k configure" instead if you want the wizard, or to see every
# available segment and option.

# Temporarily change shell options so the settings below behave the same
# way regardless of what is already set in the interactive shell.
'builtin' 'local' '-a' 'p10k_config_opts'
[[ ! -o 'aliases'         ]] || p10k_config_opts+=('aliases')
[[ ! -o 'sh_glob'         ]] || p10k_config_opts+=('sh_glob')
[[ ! -o 'no_brace_expand' ]] || p10k_config_opts+=('no_brace_expand')
'builtin' 'setopt' 'no_aliases' 'no_sh_glob' 'brace_expand'

() {
  emulate -L zsh -o extended_glob
  unsetopt 'aliases'

  # Stop p10k from launching the wizard automatically now that this file exists.
  typeset -g POWERLEVEL9K_DISABLE_CONFIGURATION_WIZARD=true

  # Silence the informational message the instant-prompt feature prints once.
  typeset -g POWERLEVEL9K_INSTANT_PROMPT=quiet

  # Requires the Nerd Font from "Install iTerm2 and the font" above.
  typeset -g POWERLEVEL9K_MODE=nerdfont-complete
  typeset -g POWERLEVEL9K_ICON_PADDING=moderate

  # -----------------------------------------------------------------
  # Prompt layout
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(
    os_icon                  # OS logo
    dir                      # current directory
    vcs                      # git branch and status
    newline                  # commands start at the left margin
    prompt_char               # a single character, red after a failed command
  )

  typeset -g POWERLEVEL9K_RIGHT_PROMPT_ELEMENTS=(
    status                   # exit code of the last command, only when non-zero
    command_execution_time   # duration, only above the threshold below
    background_jobs          # count of background jobs, if any
    context                  # user@host
    kubecontext               # kubectl context, only for kubectl-family commands
    terraform                 # Terraform workspace, only for terraform commands
    aws                       # AWS_PROFILE, only for aws and terraform commands
    time                       # HH:MM:SS, 24-hour
  )

  typeset -g POWERLEVEL9K_PROMPT_ADD_NEWLINE=true

  # -----------------------------------------------------------------
  # dir
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_SHORTEN_STRATEGY=truncate_to_unique
  typeset -g POWERLEVEL9K_SHORTEN_DIR_LENGTH=3
  typeset -g POWERLEVEL9K_DIR_MAX_LENGTH=80
  typeset -g POWERLEVEL9K_DIR_FOREGROUND=31

  # -----------------------------------------------------------------
  # vcs (git)
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_VCS_CLEAN_FOREGROUND=76
  typeset -g POWERLEVEL9K_VCS_MODIFIED_FOREGROUND=178
  typeset -g POWERLEVEL9K_VCS_UNTRACKED_FOREGROUND=178
  typeset -g POWERLEVEL9K_VCS_CONFLICTED_FOREGROUND=196

  # -----------------------------------------------------------------
  # status / command_execution_time / background_jobs
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_STATUS_OK=false
  typeset -g POWERLEVEL9K_STATUS_ERROR_FOREGROUND=231
  typeset -g POWERLEVEL9K_STATUS_ERROR_BACKGROUND=196

  typeset -g POWERLEVEL9K_COMMAND_EXECUTION_TIME_THRESHOLD=3
  typeset -g POWERLEVEL9K_COMMAND_EXECUTION_TIME_PRECISION=0
  typeset -g POWERLEVEL9K_COMMAND_EXECUTION_TIME_FOREGROUND=101

  typeset -g POWERLEVEL9K_BACKGROUND_JOBS_FOREGROUND=37

  # -----------------------------------------------------------------
  # context (user@host)
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_CONTEXT_TEMPLATE='%n@%m'
  typeset -g POWERLEVEL9K_CONTEXT_FOREGROUND=180
  typeset -g POWERLEVEL9K_CONTEXT_ROOT_FOREGROUND=231
  typeset -g POWERLEVEL9K_CONTEXT_ROOT_BACKGROUND=196

  # -----------------------------------------------------------------
  # kubecontext
  # See "Configure Powerlevel10k and make production visible" above for
  # what SHOW_ON_COMMAND and the *_CLASSES pattern do.
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_KUBECONTEXT_SHOW_ON_COMMAND='kubectl|helm|kubens|kubectx|k9s|stern|flux|skaffold'
  typeset -g POWERLEVEL9K_KUBECONTEXT_CLASSES=(
    '*prod*'  PROD
    '*'       DEFAULT)
  typeset -g POWERLEVEL9K_KUBECONTEXT_PROD_FOREGROUND=196
  typeset -g POWERLEVEL9K_KUBECONTEXT_PROD_VISUAL_IDENTIFIER_EXPANSION='!'
  typeset -g POWERLEVEL9K_KUBECONTEXT_DEFAULT_FOREGROUND=66

  # -----------------------------------------------------------------
  # terraform / aws
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_TERRAFORM_SHOW_ON_COMMAND='terraform|tf'
  typeset -g POWERLEVEL9K_TERRAFORM_FOREGROUND=105

  typeset -g POWERLEVEL9K_AWS_SHOW_ON_COMMAND='aws|terraform|tf'
  typeset -g POWERLEVEL9K_AWS_FOREGROUND=208

  # -----------------------------------------------------------------
  # time
  # -----------------------------------------------------------------
  typeset -g POWERLEVEL9K_TIME_FORMAT='%D{%H:%M:%S}'
  typeset -g POWERLEVEL9K_TIME_FOREGROUND=66
}

# Restore the shell options changed above.
(( ! ${#p10k_config_opts} )) || setopt ${p10k_config_opts[@]}
'builtin' 'unset' 'p10k_config_opts'

Back up any existing file first, save the content above as ~/.p10k.zsh, then restart Zsh. The ~/.zshrc line from the previous section, [[ ! -f ~/.p10k.zsh ]] || source ~/.p10k.zsh, sources it automatically:

$ cp ~/.p10k.zsh ~/.p10k.zsh.bak 2>/dev/null; true
$ open -e ~/.p10k.zsh
# paste the content above, save, then:
$ exec zsh

iTerm2 tips for incidents

These shortcuts come from the iTerm2 menu definitions in the official source repository.

Split panes

During an incident you often watch several things at once, such as application logs next to a metrics query.

• Cmd + D: split the current pane vertically (menu item “Split Vertically with Current Profile”).
• Cmd + Shift + D: split the current pane horizontally (“Split Horizontally with Current Profile”).
• Cmd + Option + arrow keys: select the pane above, below, left or right.
• Cmd + ] and Cmd + [: select the next and previous pane.

Profiles per environment

1. Press Cmd + , to open the preferences and go to Profiles.
2. Create a new profile and name it Production.
3. In the color settings of that profile, choose a clearly different background.
4. Use this profile only for production sessions.

Search the terminal output

Cmd + F opens Find in the current session, which is useful to locate an earlier command or an error message in a long output.

More aliases, with a warning

Check the plugin READMEs first: many aliases you would write already exist.

# Only add aliases that no plugin already provides
alias kctx="kubectx"
alias kns="kubens"
alias lzd="lazydocker"

# A readable docker ps (uses the "table" format from the Docker CLI docs)
alias dpst='docker ps --format "table {{.Names}}t{{.Status}}t{{.Ports}}"'

Two details. The name lzd is the alias suggested in the lazydocker README. Avoid ld for lazydocker, because ld is already the name of the system linker. And think twice before you alias a destructive command: an alias that runs terraform destroy in three keystrokes is a risk, not a shortcut.

Maintenance and updates

Keep the tools up to date, but read what changes before you upgrade tools you depend on.

$ brew update && brew upgrade

$ omz update

$ git -C "${ZSH_CUSTOM:-$HOME/.oh-my-zsh/custom}/themes/powerlevel10k" pull

Kubernetes tools: kubectx, kubens, k9s and lazydocker

Three tools are useful every day with Kubernetes: kubectx, kubens and k9s. lazydocker is an optional terminal UI for Docker.

kubectx and kubens: switch context and namespace

Both tools come from the same repository. The Homebrew formula kubectx installs both commands.

$ brew install kubectx

Usage, following the examples in the project README:

$ kubectx staging
Switched to context "staging".
$ kubectx -
# switch back to the previous context
$ kubens kube-system
Context "staging" set.
Active namespace is "kube-system".
$ kubens -
# switch back to the previous namespace

Both commands support Tab completion in Zsh. If you install fzf, running kubectx or kubens without arguments opens an interactive menu with fuzzy search. Without fzf, the commands do not present that menu. Set KUBECTX_IGNORE_FZF=1 to opt out of the menu when fzf is installed.

$ brew install fzf

k9s: a terminal UI for Kubernetes

k9s is a terminal UI that continuously watches a cluster and lets you navigate, view and manage resources with keyboard commands.

$ brew install k9s
$ k9s

Some key bindings from the k9s README:

# Optional: open k9s on a given context (adapt the context name)
alias k9s-staging="kubectx staging && k9s"
alias k9s-prod="kubectx prod-eu1 && k9s --readonly"

lazydocker: a terminal UI for Docker (optional)

According to its README, lazydocker lets you view the state of your Docker or Docker Compose environment at a glance, view container logs and resource metrics, and restart, remove or rebuild containers and services. It needs a working Docker installation.

$ brew install lazydocker
$ lazydocker

It is aimed at local development and debugging. For production clusters, Kubernetes tools such as k9s are the relevant ones.

Summary

Other DevOps and SRE tools

The commands below install common command-line tools with Homebrew.

Terraform and the HashiCorp tap

Terraform is not in the main Homebrew repository (homebrew-core). It comes from the HashiCorp tap, which also provides other HashiCorp tools such as Vault and Packer:

$ brew tap hashicorp/tap
$ brew install hashicorp/tap/terraform

A general toolset

$ brew install git kubernetes-cli helm awscli checkov jq yq

These formulae exist in the main Homebrew repository. kubernetes-cli provides kubectl. To run containers you also need a container engine, for example Docker Desktop (Homebrew cask docker-desktop). The Homebrew docker formula is built from the Docker CLI repository, so it provides the command-line client only.

Optional: TFLint

The TFLint README lists this Homebrew command, as well as downloads from its GitHub releases page:

$ brew install terraform-linters/tap/tflint

Check the installation

$ terraform version
$ kubectl version --client
$ helm version
$ aws --version

The output depends on the versions installed on your Mac.

What you have now

After following this guide you have:

• iTerm2 with split panes and a Production profile as a visual cue
• Powerlevel10k showing your Kubernetes context, Terraform workspace and AWS profile when they are relevant
• Oh My Zsh plugins for Git, Docker, Kubernetes, Helm, Terraform, AWS and Homebrew, with completion and aliases
• zsh-autosuggestions and zsh-syntax-highlighting for faster and safer command entry
• kubectx, kubens and k9s to switch and observe clusters quickly

Official documentation

• Homebrew: installation
• Homebrew: command-not-found handler
• Oh My Zsh (README)
• Oh My Zsh: plugins (one README per plugin)
• Powerlevel10k (README)
• zsh-autosuggestions (README)
• zsh-syntax-highlighting (installation)
• The Fuck (README)
• iTerm2 source repository (main menu definition with the shortcuts)
• kubectx and kubens (README)
• k9s (README)
• lazydocker (README)
• Docker CLI reference: docker container ls

Keep going