[Hub](https://github.com/github/hub) needs to be installed if you want to use it. On OS X with Homebrew, this can be done with `brew install hub`. The `hub` completion definition needs to be added to your `$FPATH` before initializing OMZ.
The [`github` Ruby gem](https://github.com/defunkt/github-gem) needs to be installed if you want to use it.
If you have installed `hub` using Homebrew, its completions may not be on your `$FPATH` if you are using the system `zsh`. Homebrew installs `zsh` completion definitions to `/usr/local/share/zsh/site-functions`, which will be on `$FPATH` for the Homebrew-installed `zsh`, but not for the system `zsh`. If you want it to work with the system `zsh`, add this to your `~/.zshrc` before it sources `oh-my-zsh.sh`.
```zsh
if (( ! ${fpath[(I)/usr/local/share/zsh/site-functions]} )); then