This is a plugin for TeamCity 4.0.2 that provides a build agent runner that invokes the xcodebuild command on MacOS X build agent hosts.
Grab the xcode-plugin.zip from the dist/ directory and place it in your TeamCity data directory's plugin subdirectory. Usually ~/.BuildServer/plugins for the user running the TeamCity server.
Once the zip file has been placed in the plugin directory, restart the TeamCity server.