gistfile1.txt

import XCPlayground
import UIKit
import Framework3

XCPSetExecutionShouldContinueIndefinitely()

var r = request(.GET, "http://en.lichess.org/api/user/peropaal")
    .response { (request, response, data, error) in
        println(request)
        println()
        println(response)
        println()
        println(error)
    }

That XCPSetExecutionShouldContinueIndefinitely() will allow you to use asynchronous code in playgrounds