buildfile

require 'buildr/jetty'
require 'readline'

define "webapp" do

  ....

  task("jetty"=>[package(:war), jetty.use]) do |task|
    jetty.deploy("http://localhost:8080", task.prerequisites.first)
    Readline::readline('[Type ENTER to stop Jetty]')
  end

end

buildfile_alternative

puts 'Press CTRL-C to stop Jetty'
trap 'SIGINT' do
  jetty.stop
end
Thread.stop

buildfile_deploy

require 'buildr/jetty'

define "webapp" do

  ....

  task("deploy-app"=>[package(:war), jetty.use]) do |task|
    class << task ; attr_accessor :url, :path ; end
    task.url = "http://localhost:8080"
    task.path = jetty.deploy(task.url, task.prerequisites.first)
  end

end