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docs/development/build-instructions-mac.md

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+# Build instructions (Mac)
+
+## Prerequisites
+
+* Mac OS X >= 10.7
+* [Xcode](https://developer.apple.com/technologies/tools/)
+* [node.js](http://nodejs.org)
+
+## Getting the code
+
+```bash
+$ git clone https://github.com/atom/atom-shell.git
+```
+
+## Bootstrapping
+
+The bootstrap script will download all necessary build dependencies and create
+build project files. Notice that we're using `ninja` to build `atom-shell` so
+there is no Xcode project generated.
+
+```bash
+$ cd atom-shell
+$ ./script/bootstrap.py
+```
+
+## Building
+
+Build both `Release` and `Debug` targets:
+
+```bash
+$ ./script/build.py
+```
+
+You can also only build the `Debug` target:
+
+```bash
+$ ./script/build.py -c Debug
+```
+
+After building is done, you can find `Atom.app` under `out/Debug`.
+
+## Tests
+
+```bash
+$ ./script/test.py
+```