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README.md

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+# build-emacs-for-osx
+
+Use this script at your own risk. It currently works for me on my own machine,
+which as of writing runs:
+
+* Mac OS X Lion 10.7.2 (11C74)
+* Xcode 4.2 (4D199)
+
+Your luck might vary. Do note that it does not build a universal application.
+The CPU architecture of the built application will be that of the machine it
+was built on.
+
+## Why?
+
+I've been using [Homebrew](http://mxcl.github.com/homebrew/) the past few
+months to build from HEAD. Homebrew comes with the [ns-toogle-fullscreen][fs]
+and [sRGB][] patches which I use.
+
+Homebrew does not build a self-contained application though, which caused
+issues for me when I needed to rollback to a specific build. I found the
+easiest way to build a completely self-contained Emacs.app nightly from a
+specific date with custom patches was to do it manually.
+
+So I decided to quickly hack together a script to automate that manual
+process. The code is a horrible hack, but it (seemingly) works as I'm writing
+this in Emacs built with it.
+
+## Internals
+
+I decided to pull Emacs' source from the GitHub mirror rather than the
+official Bzr repo cause I'm not familiar with Bzr, and GitHub lets you easily
+download tarballs of any commit.
+
+The only option passed in `./configure` is `--with-ns`, meaning the resulting
+application only supports the CPU architecture of the system is was built on.
+There might be more side-effects to.
+
+
+[fs]: https://gist.github.com/1012927
+[srgb]: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8402