Setting up a new computer with Homebrew

This page is part of my digital garden. It is more like a notebook entry than a polished blog post. It's a space where I document learnings primarily for my own reference, yet share them in case they benefit others. Unlike my blog posts, these pages are works-in-progress and updated over time. Like tending to a real garden, I periodically refine its content. I welcome suggestions for improvements at dries@buytaert.net.

Setting up a new computer can be a lot of work, but I've made it much simpler with Homebrew, a popular package manager.

Creating a list of installed software

As a general rule, I prefer to install all software on my Mac using Homebrew. I always try Homebrew first and only resort to downloading software directly from websites if it is not available through Homebrew.

Homebrew manages both formulae and casks. Casks are typically GUI applications, while formulae are command-line tools or libraries. To keep these two types of packages organized and avoid potential conflicts, I save them in separate lists.

First, I generate a list of all manually installed formulae on my old computer:

$ brew leaves > brews.txt

The brew leaves command displays only the formulae you installed directly using Homebrew. It excludes any formulae that were installed automatically as dependencies. To view all installed formulae, including dependencies, you can use the brew list command.

Next, I generate a separate list for installed casks:

$ brew list –cask > casks.txt

This keeps the formulae (brews.txt) and casks (casks.txt) in distinct files, avoiding any ambiguity.

Reviewing your packages

It is a good idea to check if you still need all packages on your new computer. I review my formulae and casks as follows:

For formulae:

$ cat brews.txt | xargs brew desc –formula –eval-all

For casks:

$ cat casks.txt | xargs brew desc –cask –eval-all

These commands provide a short description for each package in your lists.

Installing your packages on a new machine

Transfer your brews.txt and casks.txt files to the new computer, install Homebrew, and run:

To install formulae:

$ xargs brew install –formula < brews.txt

To install casks:

$ xargs brew install –cask < casks.txt