using with phoenix

This guide will walk through setting up a Phoenix project with Elixirscript. This guide assumes you have already created a Phoenix project

Update: 2017-08-15: This guide has been updated to cover both ElixirScript 0.30 and Phoenix 1.3

Update your mix.exs file to add the current version of elixirscript to your dependencies:

  defp deps do
      #other deps
     {:elixir_script, "~> x.x"}

Run mix deps.get:

mix deps.get

Next, Add the elixir_script compiler to your list of mix compilers. Also add in the elixir_script configuration:

def project do
  [app: :my_app,
    version: "0.0.1",
    elixir: "~> 1.2",
    elixirc_paths: elixirc_paths(Mix.env),
    compilers: [:phoenix, :gettext] ++ Mix.compilers ++ [:elixir_script],
    build_embedded: Mix.env == :prod,
    start_permanent: Mix.env == :prod,
    deps: deps(),
    elixir_script: [
      input: MyApp.App,
      output: "assets/js/build"

Make the input the entry point module of your ElixirScript App. Here is will be MyApp.App which we will define later. Next, add the output to the configuration and make it "assets/js/build". By default the output goes to priv/elixir_script/build, but we want to place our output somewhere that our asset compilation process can pick it up and bundle it with any other JavaScript.

Create app.ex in the lib/my_app_frontend directory

touch lib/my_app_frontend/app.ex

For this example, write a simple module that will write Hello, world to the console on start:

defmodule MyApp.App do

  def start(_type, _args) do
    IO.puts("Hello, world")


Finally, update assets/js/app.js to start your Elixirscript app:

import Elixir from './build/';
Elixir.start(Elixir.MyApp.App, [])

The empty array is list of initial arguments for your app.

If you run mix compile, you should see a JavaScript file, in your assets/js/build directory.

If you run mix phx.server, open your browser, and then open your console, you should see Hello, world. Any changes should cause a recompilation of your ElixirScript code and a reload of the browser