Homebrew

What is Homebrew?

Homebrew is a package manager for macOS (and Linux) that lets you easily install software from the command line. Think of it like an app store for your terminal - instead of downloading software from websites, extracting files, and manually installing them, you can just type something like brew install python and Homebrew handles all the downloading, installing, and setting up for you.

The name comes from the idea of "brewing" your own software setup, and it's become the standard way most Mac developers manage their development tools.

Is Homebrew pre-installed on macOS?

No, Homebrew is not pre-installed on macOS. You need to install it yourself using this command in Terminal:

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

How do I check if Homebrew is installed?

Run this command in Terminal:

brew --version

If it shows a version number, Homebrew is installed and working.

Basic Homebrew Commands

• brew install [package] - Install a package
• brew uninstall [package] - Remove a package
• brew update - Update Homebrew itself
• brew upgrade - Update all installed packages
• brew upgrade [package] - Update a specific package
• brew list - Show all installed packages
• brew search [term] - Search for available packages
• brew info [package] - Get detailed information about a package
• brew doctor - Check for common issues and problems

What's the difference between brew install and brew install --cask?

• brew install [package] - Installs command-line tools and libraries (like git, python, node)
• brew install --cask [package] - Installs GUI applications (like Chrome, VS Code, Slack)

For example:

• brew install git - Installs the Git command-line tool
• brew install --cask google-chrome - Installs Google Chrome browser

Where does Homebrew install packages?

Homebrew installs packages in /opt/homebrew on Apple Silicon Macs (M1/M2) and /usr/local on Intel Macs. It creates symbolic links in /opt/homebrew/bin or /usr/local/bin so you can use the commands from anywhere.

How do I update Homebrew and my packages?

1. Update Homebrew itself: brew update
2. Update all installed packages: brew upgrade
3. Update a specific package: brew upgrade [package]

It's good practice to run brew update before installing new packages to ensure you have the latest package information.

How do I uninstall Homebrew completely?

Run this command in Terminal:

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

What should I do if I get permission errors?

Never use sudo with Homebrew commands. If you're getting permission errors:

1. Make sure you own the Homebrew directories: sudo chown -R $(whoami) /opt/homebrew (or /usr/local on Intel Macs)
2. Run brew doctor to diagnose issues
3. If problems persist, consider reinstalling Homebrew

How do I see what packages I have installed?

• brew list - Show all installed packages
• brew list --cask - Show only GUI applications (casks)
• brew deps [package] - Show dependencies for a specific package

Can I install a specific version of a package?

Homebrew typically only maintains the latest version of packages. For older versions, you might need to:

• Use version managers (like nvm for Node.js, pyenv for Python)
• Install from source
• Use Homebrew's versioned formulas when available (like python@3.9)

What's a Homebrew formula vs. a cask?

• Formula: Recipe for installing command-line tools and libraries
• Cask: Extension for installing GUI applications

How do I troubleshoot Homebrew issues?

1. Run brew doctor - This checks for common problems
2. Run brew update - Ensures you have the latest package information
3. Check the Homebrew GitHub issues page
4. Look at the installation logs for specific error messages

Common Homebrew Commands Cheat Sheet

# Installation
brew install [package]
brew install --cask [app]
 
# Information
brew search [term]
brew info [package]
brew list
brew deps [package]
 
# Maintenance
brew update
brew upgrade
brew upgrade [package]
brew cleanup
 
# Troubleshooting
brew doctor
brew config

Best Practices

• Run brew update regularly to keep package information current
• Use brew upgrade periodically to update installed packages
• Run brew cleanup occasionally to remove old versions and free up space
• Use brew doctor if you encounter any issues
• Don't use sudo with Homebrew commands
• Keep your macOS up to date for best compatibility

Getting Help

• brew help - Shows general help
• brew help [command] - Shows help for a specific command
• Visit brew.sh for official documentation
• Check the Homebrew GitHub repository for issues and discussions