AlamoFire doesn't seem to be working with CocoaPods for tvOS - here is the info and the error message.
pod --version - 0.39.0
Podfile:
platform :tvos, '9.0'
pod 'Alamofire', :git => 'https://github.com/Alamofire/Alamofire.git', :branch => 'tvOS'
Terminal:
> pod install
Updating local specs repositories
Analyzing dependencies
Pre-downloading: `Alamofire` from `https://github.com/Alamofire/Alamofire.git`, branch `tvOS`
[!] Error installing Alamofire
[!] /usr/bin/git clone https://github.com/Alamofire/Alamofire.git /var/folders/w_/90_3ly_d1xl6t0gfg9xmr52w0000gn/T/d20151111-1787-1j3pdql --single-branch --depth 1 --branch tvOS
Cloning into '/var/folders/w_/90_3ly_d1xl6t0gfg9xmr52w0000gn/T/d20151111-1787-1j3pdql'...
warning: Could not find remote branch tvOS to clone.
fatal: Remote branch tvOS not found in upstream origin
You no longer need to use a specific branch, apparently the tvOS branch already has been merged into master, and it doesn't exist anymore.