http://qiita.com/HirofumiTamori/items/7936ed9c6f73f4c9b475 を真似て書いた。ubuntu 14.04 Elixir (1.0.5)で動作確認。 iex -S mixで動く。

mix.exs

defmodule Vercheckex.Mixfile do
  use Mix.Project

  def project do
    [app: :vercheckex,
     version: "0.0.1",
     elixir: "~> 1.0",
     build_embedded: Mix.env == :prod,
     start_permanent: Mix.env == :prod,
     deps: deps]
  end

  # Configuration for the OTP application
  #
  # Type `mix help compile.app` for more information
  def application do
    [applications: [:logger,:httpoison,:floki,:timex]]
  end

  # Dependencies can be Hex packages:
  #
  #   {:mydep, "~> 0.3.0"}
  #
  # Or git/path repositories:
  #
  #   {:mydep, git: "https://github.com/elixir-lang/mydep.git", tag: "0.1.0"}
  #
  # Type `mix help deps` for more examples and options
  defp deps do
    [{:httpoison, "~> 0.7.2"},  {:floki, "~> 0.3"},{:timex, "~> 0.19.2"}]
  end
end

VercheckEx.ex

defmodule VercheckEx do
  # requireで使用するライブラリを指定
  require HTTPoison
  require Floki
  require Timex
  use Timex
  def fetch_content() do
    IO.puts("fetch_content")
    receive do
      {caller,url,type,i} ->
        IO.puts("i=#{i}")
        ret = HTTPoison.get!( url ) # urlで指定されるページのデータを取得
        %HTTPoison.Response{status_code: 200, body: body} = ret
        # HTML bodyを取得する
        # HTMLパーザー Flokiで処理
        # 名前、リリース日時を取得
        {_,_,n} = Floki.find(body, "[itemprop=title]") |> List.first
        {_, date} = Floki.find(body, "time") |> Floki.attribute("datetime")
                                             |> List.first
                                             |> Timex.DateFormat.parse("{ISOz}")

        if(type == :type1) do # バージョン番号を取得
          {_,_,x} = Floki.find(body, ".tag-name span") |> List.first
        else
          {_,_,x} = Floki.find(body, ".css-truncate-target span") |> List.first
        end
        #UTC時刻をJSTに変更
        date |> DateConvert.to_erlang_datetime
        |> Timex.Date.from "Asia/Tokyo"
        send caller ,{:ok,{hd(n),hd(x),date,i}} # 戻り値はタプル
    end
  end
  def put_a_formatted_line(val) do # 1行出力
    {title, ver, date,_} = val
    l = title
    if String.length(title) < 8 do
      l = l <> "\t"
    end
    l = l <> "\t" <> ver
    if String.length(ver) < 8 do
      l = l <> "\t"
    end
    l = l <> "\t" <> Timex.DateFormat.format!(date, "%Y.%m.%d", :strftime)
    now = Timex.Date.now("JST")
    diff =  Timex.Date.diff( date, now, :days) # リリースから今日までの日数
    if diff < 14 do # 14日以内なら警告する。以前の仕事が2週間スプリントだった名残り。
      l = l <> "\t<<<<< updated at " <> Integer.to_string(diff) <> " day(s) ago."
    end
    IO.puts(l)
  end
  def receiver(result_list,n) do
    IO.puts("receiver")
    if(length(result_list) < n) do
      receive do
        {:ok,res} ->
          IO.puts("n=#{length(result_list)}")
          receiver(result_list++[res],n)
      end
    else
      Enum.sort(result_list,fn(a,b)->
        {_,_,_,i1} = a
        {_,_,_,i2} = b
        i1 < i2 end
      )|>Enum.each(
        fn(x) -> put_a_formatted_line x end
      )
    end
  end
end
urls = [
  {"https://github.com/jquery/jquery/releases", :type1},
  {"https://github.com/angular/angular/releases", :type1},
  {"https://github.com/facebook/react/releases", :type2},
  {"https://github.com/PuerkitoBio/goquery/releases", :type1},
  {"https://github.com/revel/revel/releases", :type2},
  {"https://github.com/lhorie/mithril.js/releases", :type1},
  {"https://github.com/riot/riot/releases", :type1},
  {"https://github.com/atom/atom/releases", :type2},
  {"https://github.com/Microsoft/TypeScript/releases", :type2},
  {"https://github.com/docker/docker/releases", :type1},
  {"https://github.com/JuliaLang/julia/releases", :type2},
  {"https://github.com/nim-lang/Nim/releases", :type1},
  {"https://github.com/elixir-lang/elixir/releases", :type2},
  {"https://github.com/philss/floki/releases", :type1},
  {"https://github.com/takscape/elixir-array/releases", :type2},
]

HTTPoison.start

IO.puts("Start")

fetchers = for _ <- 0..length(urls) , do: spawn_link fn -> VercheckEx.fetch_content() end

IO.puts("fetchers")

Enum.each( Enum.with_index(urls),fn(x)->
  {{u,t},i} = x
  IO.puts("pre send enum i = #{i}")
  send Enum.at(fetchers,i),{self,u,t,i}
end)

result_list = []
VercheckEx.receiver(result_list,length(urls))