The Incredible Brew

The missing package manager for OS X which solves a lot of headaches.

Posted on December 7, 2013 unix, osx, tool, git, ruby, bash .

When Apple started shipping the first iBooks including Mac OS X back in 2001 I was hooked. A beautiful and well design user interface sitting on top of a developer friendly operation system. More importantly: a unix based OS where most of the unix tools you know and love are available. But porting some linux based utility to Mac Os was now possible albeit quite hairy in some cases. Dealing with the dependencies and taking care that versions are compatible gets ungainly pretty quick.

Package Management Systems

And of course there where others that stepped up and created whole package management systems: fink and MacPorts (formerly DarwinPorts) where the first contenders. While this ameliorated the whole situation considerably I still couldn’t quite warm up to those solutions. Both systems decided it was best to not rely on any library that come with OS X but rather include everything in the dependency-tree. That for sure does guarantee the best possible compatibility but it also means build times will increase dramatically. MacPorts was long my favorite solution and over time I assembled quite a fair share of compiled libraries. So much that you will avoid rebuilding at all costs. If for some reason your dependencies are messed up and you’d like to restart…you won’t do it.

Homebrew to the Rescue

Homebrew takes a radically different approach: reuse existing Mac OS libraries and stay as lightweight as possible. Everything about homebrew has a modern feel to it, from the homepage over the way they keep all package information in a git-repository to the super easy formula (that’s what they call their packages) definitions in ruby. It has a very active user community and since development is done on github, it’s quite easy to follow along and participate.
The usual stuff works as expected:

  • brew update – update the formulae and Homebrew itself
  • brew outdated – now find out what is outdated
  • brew upgrade – Upgrade everything
  • brew upgrade $FORMULA – upgrade a specific formula
  • brew search /.*tk$/ – search for available formula
  • brew info $FORMULA – provides a little more info about a formula
tmp > brew info aubio
    aubio: stable 0.3.2
    http://aubio.org/
    Not installed
    From: https://github.com/mxcl/homebrew/commits/master/Library/Formula/aubio.rb
    ==> Dependencies
    Build: pkg-config ✔, libtool ✔, swig ✘
    Required: fftw ✘, libsamplerate ✘, libsndfile ✘
    ...

The search command can be used with regular expressions if the search term is surrounded with slashes. A lesser known brew way to search for packages/formulae is to use brew server. This requires that sinatra is available on the system and provides a website for the search.

Of course you can always look up a package online as e.g. on braumeister. And if you need a package that is not yet part of homebrew, it can easily be created. All it takes is to locate the sources on the web and call brew create with this link. homebrew will create a basic formula (== a ruby script) that you can either just use or tweak manually of some special configure options are needed. Since all formulae are kept in a git repository, it’s no problem to create your own packages and still keep up to date with homebrew. In fact, it’s so easy to modify a formula and have it added to the official repository that a lot of people are contributing to keep everything up to date and grow the pool of available formulae constantly.

Warm and Fuzzy

Good package managing systems have one area that is crucial in the long run: help to maintain a tidy system. An area where brew really shines is dependency tracking. To find out if it’s gonna be a quick install or quite a beast just take a look at the dependencies a formula has:

tmp > brew deps cairo --tree
cairo
|- xz
|- pkg-config
|- freetype
|  |- libpng
|- fontconfig
|  |- pkg-config
|  |- freetype
|  |  |- libpng
...

To maintain a sleek and tidy brew installation you can easily get rid of installed formulae. Here it’s quite handy to do a reverse dependency lookup before:

tmp > brew uses --recursive readline
abcl			geocouch		...
abook			ginac			...
...

Once you decide what to get rid of, it just takes a brew uninstall or a brew rm. To make sure nothing unimportant remains in your system, brew prune will remove dead symlinks and brew cleanup -s will remove older versions and all downloads.
Brew also comes with some extremely useful checks. The brew doctor makes sure you are in good shape and gives you good advice.

tmp > brew doctor
Warning: Your XQuartz (2.7.4) is outdated
Please install XQuartz 2.7.5:
  https://xquartz.macosforge.org
Warning: Some installed formula are missing dependencies.
You should `brew install` the missing dependencies:
    brew install libffi
Run `brew missing` for more details.
...

It tremendously helps to clean up and allows you to keep your peace of conscience. And brew missing of course shows you all formulae you still need to install.

Absolutely Happy

When I found out about brew a couple of years back, I was thrilled by it’s simplicity and the basic concepts behind brew. Today after having used brew on multiple OS versions and machines, brew is one of the first things to install. So far it never failed me and watching brew install a formula including all necessary dependencies is almost a calming experience. Looking forward to a lot of future installs!

image: Cheers designed by Ryan Beck, both from the Noun Project