OS X has become a popular platform for developing Ruby on Rails applications; as such, if you run OS X, you might find it more congenial to work on **[Discourse](http://discourse.org)** in your native environment. These instructions should get you there.
Obviously, if you **already** develop Ruby on OS X, a lot of this will be redundant, because you'll have already done it, or something like it. If that's the case, you may well be able to just install Ruby 2.0 using RVM and get started! Discourse has enough dependencies, however (note: not a criticism!) that there's a good chance you'll find **something** else in this document that's useful for getting your Discourse development started!
If you don't already have a Ruby environment that's tuned to your liking, you can do most of this set up in just a few steps:
1. Install XCode and/or the XCode Command Line Tools from [Apple's developer site](https://developer.apple.com/downloads/index.action). This should also install Git.
As the [RVM website](http://rvm.io) makes clear, there are some serious issues between MRI Ruby and the modern Xcode command line tools, which are based on CLANG and LLVM, rather than classic GCC.
This means that you need to do a little bit of groundwork if you do not already have an environment that you know for certain yields working rubies and gems.
You will want to install XCode Command Line Tools. If you already have XCode installed, you can do this from within XCode's preferences. You can also install just the command line tools, without the rest of XCode, at [Apple's developer site](https://developer.apple.com/downloads/index.action). You will need these more for some of the headers they include than the compilers themselves.
You will then need the old GCC-4.2 compilers, which leads us to...
## Homebrew
**[Homebrew](http://mxcl.github.com/homebrew)** is a package manager for ports of various Open Source packages that Apple doesn't already include (or newer versions of the ones they do), and competes in that space with MacPorts and a few others. Brew is very different from Apt, in that it often installs from source, and almost always installs development files as well as binaries, especially for libraries, so there are no special "-dev" packages.
RVM (below) can automatically install homebrew for you with the autolibs setting, but doesn't install the GCC-4.2 compiler package when it does so, possibly because that package is not part of the mainstream homebrew repository.
So, you will need to install Homebrew separately, based on the instructions at the website above, and then run the following from the command line:
If you don't have RVM installed, the "official" install command line on rvm.io will take care of just about everything you need, including installing Homebrew if you don't already have it installed. If you do, it will bring things up to date and use it to install the packages it needs.
Atlassan has a free Git client for OS X called [SourceTree](http://www.sourcetreeapp.com/download/) which can be extremely useful for keeping visual track of what's going on in Git-land. While it's arguably not a full substitute for command-line git (especially if you know the command line well), it's extremely powerful for a GUI version-control client.
After installing the [Postgres93 App](http://postgresapp.com/), there is some additional setup that is necessary for discourse to create a database on your machine.
And change these two lines so that postgres will create a socket in the folder discourse expects it to:
```
unix_socket_directories = '/var/pgsql_socket'»# comma-separated list of directories
#and
unix_socket_permissions = 0777»·»·# begin with 0 to use octal notation
```
Then create the '/var/pgsql/' folder and set up the appropriate permission in your bash (this requires admin access)
```
sudo mkdir /var/pgsql_socket
sudo chmod 770 /var/pgsql_socket
sudo chown root:staff /var/pgsql_socket
```
Now you can restart Postgres.app and it will use this socket. Make sure you not only restart the app but kill any processes that may be left behind. You can view these processes with this bash command:
Whereas Ubuntu installs postgres with 'postgres' as the default superuser, Homebrew installs it with the user who installed it... but with 'postgres' as the default database. Go figure.
However, the seed data currently has some dependencies on their being a 'postgres' user, so we create one below.
In theory, you're not setting up with vagrant, either, and shouldn't need a vagrant user; however, again, all the seed data assumes 'vagrant'. To avoid headaches, it's probably best to go with this flow, so again, we create a 'vagrant' user.
